WEBVTT Kind: captions Language: en 00:00:09.190 --> 00:00:17.400 align:start position:0% [Music] 00:00:17.400 --> 00:00:17.410 align:start position:0% 00:00:17.410 --> 00:00:21.300 align:start position:0% okay<00:00:18.410> my<00:00:18.710> name<00:00:18.890> is<00:00:18.920> Sergio<00:00:19.430> Leone<00:00:19.640> learner<00:00:19.910> and 00:00:21.300 --> 00:00:21.310 align:start position:0% okay my name is Sergio Leone learner and 00:00:21.310 --> 00:00:25.450 align:start position:0% okay my name is Sergio Leone learner and I'm<00:00:22.310> if<00:00:23.240> you<00:00:23.450> find<00:00:23.900> and<00:00:24.320> if<00:00:24.590> you<00:00:24.740> part<00:00:25.280> of<00:00:25.340> the 00:00:25.450 --> 00:00:25.460 align:start position:0% I'm if you find and if you part of the 00:00:25.460 --> 00:00:26.860 align:start position:0% I'm if you find and if you part of the Syrian<00:00:25.700> community<00:00:26.060> since<00:00:26.300> its<00:00:26.510> beginning 00:00:26.860 --> 00:00:26.870 align:start position:0% Syrian community since its beginning 00:00:26.870 --> 00:00:29.620 align:start position:0% Syrian community since its beginning when<00:00:27.650> I<00:00:27.680> did<00:00:27.980> the<00:00:28.130> first<00:00:28.340> security<00:00:29.090> audit<00:00:29.390> of 00:00:29.620 --> 00:00:29.630 align:start position:0% when I did the first security audit of 00:00:29.630 --> 00:00:34.090 align:start position:0% when I did the first security audit of the<00:00:29.890> code<00:00:30.890> and<00:00:31.130> design<00:00:31.490> and<00:00:32.829> currently<00:00:33.829> I<00:00:33.860> work 00:00:34.090 --> 00:00:34.100 align:start position:0% the code and design and currently I work 00:00:34.100 --> 00:00:36.970 align:start position:0% the code and design and currently I work for<00:00:34.579> a<00:00:34.610> company<00:00:34.760> called<00:00:34.970> SK<00:00:35.780> labs<00:00:36.050> which<00:00:36.860> is 00:00:36.970 --> 00:00:36.980 align:start position:0% for a company called SK labs which is 00:00:36.980 --> 00:00:40.900 align:start position:0% for a company called SK labs which is developing<00:00:37.520> an<00:00:37.930> incompatible<00:00:39.610> sidechain<00:00:40.610> to 00:00:40.900 --> 00:00:40.910 align:start position:0% developing an incompatible sidechain to 00:00:40.910 --> 00:00:44.260 align:start position:0% developing an incompatible sidechain to Bitcoin<00:00:41.560> but<00:00:42.560> today's<00:00:43.100> talk<00:00:43.430> is<00:00:43.610> about<00:00:43.880> a 00:00:44.260 --> 00:00:44.270 align:start position:0% Bitcoin but today's talk is about a 00:00:44.270 --> 00:00:46.569 align:start position:0% Bitcoin but today's talk is about a research<00:00:45.230> I<00:00:45.440> did<00:00:45.500> a<00:00:45.680> couple<00:00:46.010> of<00:00:46.190> years<00:00:46.250> ago 00:00:46.569 --> 00:00:46.579 align:start position:0% research I did a couple of years ago 00:00:46.579 --> 00:00:49.479 align:start position:0% research I did a couple of years ago that<00:00:46.730> applies<00:00:47.690> both<00:00:48.470> to<00:00:48.530> aetherium 00:00:49.479 --> 00:00:49.489 align:start position:0% that applies both to aetherium 00:00:49.489 --> 00:00:52.450 align:start position:0% that applies both to aetherium and<00:00:49.820> towards<00:00:50.360> K<00:00:50.660> and<00:00:50.989> to<00:00:51.290> any<00:00:51.500> other<00:00:51.680> blogging 00:00:52.450 --> 00:00:52.460 align:start position:0% and towards K and to any other blogging 00:00:52.460 --> 00:00:56.020 align:start position:0% and towards K and to any other blogging platform<00:00:53.180> so<00:00:53.690> the<00:00:54.230> talks<00:00:54.470> name<00:00:55.130> is<00:00:55.340> the 00:00:56.020 --> 00:00:56.030 align:start position:0% platform so the talks name is the 00:00:56.030 --> 00:00:58.299 align:start position:0% platform so the talks name is the blockchain<00:00:56.270> buyers<00:00:56.720> can<00:00:57.559> a<00:00:57.590> blockchain<00:00:57.860> pay 00:00:58.299 --> 00:00:58.309 align:start position:0% blockchain buyers can a blockchain pay 00:00:58.309 --> 00:01:01.540 align:start position:0% blockchain buyers can a blockchain pay to<00:00:58.370> replicate<00:00:59.140> can<00:01:00.140> a<00:01:00.410> blockchain<00:01:00.800> itself 00:01:01.540 --> 00:01:01.550 align:start position:0% to replicate can a blockchain itself 00:01:01.550 --> 00:01:05.079 align:start position:0% to replicate can a blockchain itself pay<00:01:02.030> for<00:01:02.660> all<00:01:02.960> their<00:01:03.380> seed<00:01:03.890> it<00:01:04.040> needs<00:01:04.309> to 00:01:05.079 --> 00:01:05.089 align:start position:0% pay for all their seed it needs to 00:01:05.089 --> 00:01:08.920 align:start position:0% pay for all their seed it needs to survive<00:01:05.390> like<00:01:05.780> a<00:01:05.810> norges<00:01:06.530> organism<00:01:07.430> or<00:01:08.030> it 00:01:08.920 --> 00:01:08.930 align:start position:0% survive like a norges organism or it 00:01:08.930 --> 00:01:10.810 align:start position:0% survive like a norges organism or it could<00:01:09.200> have<00:01:09.409> been<00:01:09.590> called<00:01:09.830> how<00:01:10.040> to<00:01:10.100> war<00:01:10.430> full 00:01:10.810 --> 00:01:10.820 align:start position:0% could have been called how to war full 00:01:10.820 --> 00:01:13.539 align:start position:0% could have been called how to war full nodes<00:01:11.090> or<00:01:11.360> it<00:01:12.110> could<00:01:12.320> have<00:01:12.530> been<00:01:12.680> called<00:01:12.950> how 00:01:13.539 --> 00:01:13.549 align:start position:0% nodes or it could have been called how 00:01:13.549 --> 00:01:16.060 align:start position:0% nodes or it could have been called how to<00:01:13.580> create<00:01:14.060> a<00:01:14.299> reward<00:01:14.810> based<00:01:15.200> peer-to-peer 00:01:16.060 --> 00:01:16.070 align:start position:0% to create a reward based peer-to-peer 00:01:16.070 --> 00:01:19.570 align:start position:0% to create a reward based peer-to-peer file<00:01:16.909> sharing<00:01:16.940> system<00:01:17.810> control<00:01:18.619> entirely<00:01:19.159> by 00:01:19.570 --> 00:01:19.580 align:start position:0% file sharing system control entirely by 00:01:19.580 --> 00:01:21.580 align:start position:0% file sharing system control entirely by smart<00:01:19.909> contracts<00:01:20.330> by<00:01:20.930> no<00:01:20.990> additional 00:01:21.580 --> 00:01:21.590 align:start position:0% smart contracts by no additional 00:01:21.590 --> 00:01:23.580 align:start position:0% smart contracts by no additional blockchain<00:01:22.070> okay 00:01:23.580 --> 00:01:23.590 align:start position:0% blockchain okay 00:01:23.590 --> 00:01:26.380 align:start position:0% blockchain okay so<00:01:24.590> first<00:01:25.070> of<00:01:25.220> all<00:01:25.369> I'm<00:01:25.580> gonna<00:01:25.790> talk<00:01:26.060> a<00:01:26.090> little 00:01:26.380 --> 00:01:26.390 align:start position:0% so first of all I'm gonna talk a little 00:01:26.390 --> 00:01:28.810 align:start position:0% so first of all I'm gonna talk a little bit<00:01:26.540> about<00:01:26.570> the<00:01:26.869> centralization<00:01:27.430> because<00:01:28.430> we 00:01:28.810 --> 00:01:28.820 align:start position:0% bit about the centralization because we 00:01:28.820 --> 00:01:31.929 align:start position:0% bit about the centralization because we wouldn't<00:01:29.030> be<00:01:29.240> here<00:01:29.690> if<00:01:30.229> not<00:01:30.530> because<00:01:31.130> we 00:01:31.929 --> 00:01:31.939 align:start position:0% wouldn't be here if not because we 00:01:31.939 --> 00:01:34.240 align:start position:0% wouldn't be here if not because we appreciate<00:01:32.150> this<00:01:32.689> in<00:01:32.840> translation<00:01:33.350> and<00:01:33.500> any 00:01:34.240 --> 00:01:34.250 align:start position:0% appreciate this in translation and any 00:01:34.250 --> 00:01:36.640 align:start position:0% appreciate this in translation and any attempt<00:01:35.030> to<00:01:35.150> build<00:01:35.420> a<00:01:35.630> cryptocurrency<00:01:35.990> or 00:01:36.640 --> 00:01:36.650 align:start position:0% attempt to build a cryptocurrency or 00:01:36.650 --> 00:01:39.160 align:start position:0% attempt to build a cryptocurrency or smart<00:01:37.100> contract<00:01:37.490> platform<00:01:37.909> in<00:01:38.060> the<00:01:38.180> past<00:01:38.420> that 00:01:39.160 --> 00:01:39.170 align:start position:0% smart contract platform in the past that 00:01:39.170 --> 00:01:42.609 align:start position:0% smart contract platform in the past that was<00:01:39.320> centralized<00:01:39.979> just<00:01:40.460> fail<00:01:40.700> okay<00:01:41.600> so<00:01:42.110> this 00:01:42.609 --> 00:01:42.619 align:start position:0% was centralized just fail okay so this 00:01:42.619 --> 00:01:45.130 align:start position:0% was centralized just fail okay so this is<00:01:42.799> what<00:01:43.040> we<00:01:43.340> must<00:01:43.520> stand<00:01:44.180> this<00:01:44.509> is<00:01:44.659> what<00:01:44.840> we 00:01:45.130 --> 00:01:45.140 align:start position:0% is what we must stand this is what we 00:01:45.140 --> 00:01:50.380 align:start position:0% is what we must stand this is what we must<00:01:45.400> try<00:01:46.400> to<00:01:46.460> to<00:01:47.060> to<00:01:47.689> keep<00:01:48.340> so<00:01:49.340> why<00:01:49.640> is<00:01:49.700> this<00:01:50.210> in 00:01:50.380 --> 00:01:50.390 align:start position:0% must try to to to keep so why is this in 00:01:50.390 --> 00:01:52.929 align:start position:0% must try to to to keep so why is this in transition<00:01:50.869> so<00:01:51.020> important<00:01:51.590> well<00:01:52.159> it<00:01:52.520> brings 00:01:52.929 --> 00:01:52.939 align:start position:0% transition so important well it brings 00:01:52.939 --> 00:01:55.780 align:start position:0% transition so important well it brings back<00:01:53.299> the<00:01:53.540> power<00:01:53.780> to<00:01:53.930> the<00:01:54.080> people<00:01:54.290> so<00:01:55.130> it<00:01:55.369> means 00:01:55.780 --> 00:01:55.790 align:start position:0% back the power to the people so it means 00:01:55.790 --> 00:01:58.480 align:start position:0% back the power to the people so it means a<00:01:56.030> lot<00:01:56.180> of<00:01:56.360> things<00:01:56.570> like<00:01:56.900> people<00:01:57.829> being<00:01:58.280> able 00:01:58.480 --> 00:01:58.490 align:start position:0% a lot of things like people being able 00:01:58.490 --> 00:02:00.039 align:start position:0% a lot of things like people being able to<00:01:58.700> audit<00:01:59.180> their<00:01:59.390> payments 00:02:00.039 --> 00:02:00.049 align:start position:0% to audit their payments 00:02:00.049 --> 00:02:03.730 align:start position:0% to audit their payments disintermediation<00:02:00.860> having<00:02:01.700> open<00:02:02.390> access<00:02:02.740> no 00:02:03.730 --> 00:02:03.740 align:start position:0% disintermediation having open access no 00:02:03.740 --> 00:02:07.179 align:start position:0% disintermediation having open access no central<00:02:04.220> control<00:02:04.299> no<00:02:05.299> monopolies<00:02:05.930> no<00:02:06.680> central 00:02:07.179 --> 00:02:07.189 align:start position:0% central control no monopolies no central 00:02:07.189 --> 00:02:09.130 align:start position:0% central control no monopolies no central point<00:02:07.220> of<00:02:07.549> failure<00:02:07.820> and<00:02:08.209> of<00:02:08.869> course 00:02:09.130 --> 00:02:09.140 align:start position:0% point of failure and of course 00:02:09.140 --> 00:02:11.380 align:start position:0% point of failure and of course censorship<00:02:09.950> resistance<00:02:10.520> and<00:02:10.759> corruption 00:02:11.380 --> 00:02:11.390 align:start position:0% censorship resistance and corruption 00:02:11.390 --> 00:02:13.780 align:start position:0% censorship resistance and corruption resistance<00:02:12.020> these<00:02:12.590> are<00:02:12.739> very<00:02:13.130> very<00:02:13.370> important 00:02:13.780 --> 00:02:13.790 align:start position:0% resistance these are very very important 00:02:13.790 --> 00:02:15.840 align:start position:0% resistance these are very very important properties<00:02:14.239> of<00:02:14.420> our<00:02:14.599> net 00:02:15.840 --> 00:02:15.850 align:start position:0% properties of our net 00:02:15.850 --> 00:02:18.720 align:start position:0% properties of our net so<00:02:16.850> how<00:02:17.210> do<00:02:17.270> we<00:02:17.510> promote<00:02:17.990> the<00:02:18.200> centralization 00:02:18.720 --> 00:02:18.730 align:start position:0% so how do we promote the centralization 00:02:18.730 --> 00:02:22.210 align:start position:0% so how do we promote the centralization well<00:02:19.730> first<00:02:20.540> we<00:02:20.900> have<00:02:21.110> to<00:02:21.140> identify<00:02:21.590> and 00:02:22.210 --> 00:02:22.220 align:start position:0% well first we have to identify and 00:02:22.220 --> 00:02:24.580 align:start position:0% well first we have to identify and measure<00:02:22.430> it<00:02:22.730> and<00:02:22.940> then<00:02:23.300> we<00:02:23.450> can<00:02:23.570> see<00:02:23.810> how<00:02:23.960> can 00:02:24.580 --> 00:02:24.590 align:start position:0% measure it and then we can see how can 00:02:24.590 --> 00:02:27.760 align:start position:0% measure it and then we can see how can we<00:02:24.860> improve<00:02:25.220> it<00:02:25.370> so<00:02:26.030> one<00:02:26.870> of<00:02:26.900> the<00:02:27.200> ways<00:02:27.440> is 00:02:27.760 --> 00:02:27.770 align:start position:0% we improve it so one of the ways is 00:02:27.770 --> 00:02:30.990 align:start position:0% we improve it so one of the ways is increasing<00:02:28.520> the<00:02:28.610> number<00:02:29.030> of<00:02:29.270> independent 00:02:30.990 --> 00:02:31.000 align:start position:0% increasing the number of independent 00:02:31.000 --> 00:02:34.080 align:start position:0% increasing the number of independent implementation<00:02:32.050> developers<00:02:33.050> full<00:02:33.740> nodes 00:02:34.080 --> 00:02:34.090 align:start position:0% implementation developers full nodes 00:02:34.090 --> 00:02:38.230 align:start position:0% implementation developers full nodes okay<00:02:35.120> and<00:02:35.300> another<00:02:36.080> way<00:02:36.320> is<00:02:36.620> by<00:02:36.910> reducing<00:02:37.910> the 00:02:38.230 --> 00:02:38.240 align:start position:0% okay and another way is by reducing the 00:02:38.240 --> 00:02:40.630 align:start position:0% okay and another way is by reducing the cost<00:02:38.510> of<00:02:38.690> running<00:02:39.200> a<00:02:39.260> full<00:02:39.470> node<00:02:39.740> because<00:02:40.430> as 00:02:40.630 --> 00:02:40.640 align:start position:0% cost of running a full node because as 00:02:40.640 --> 00:02:43.450 align:start position:0% cost of running a full node because as the<00:02:40.940> network<00:02:41.330> scales<00:02:41.780> the<00:02:42.530> cost<00:02:42.770> of<00:02:42.920> running<00:02:43.100> a 00:02:43.450 --> 00:02:43.460 align:start position:0% the network scales the cost of running a 00:02:43.460 --> 00:02:47.010 align:start position:0% the network scales the cost of running a full<00:02:43.760> node<00:02:44.000> increases<00:02:44.750> so<00:02:45.080> if<00:02:45.620> I<00:02:45.800> have<00:02:46.130> to 00:02:47.010 --> 00:02:47.020 align:start position:0% full node increases so if I have to 00:02:47.020 --> 00:02:51.910 align:start position:0% full node increases so if I have to depend<00:02:48.020> on<00:02:48.320> a<00:02:48.470> third<00:02:48.740> party<00:02:48.770> to<00:02:49.730> know<00:02:50.680> about<00:02:51.680> my 00:02:51.910 --> 00:02:51.920 align:start position:0% depend on a third party to know about my 00:02:51.920 --> 00:02:54.820 align:start position:0% depend on a third party to know about my transactions<00:02:52.670> then<00:02:53.060> the<00:02:53.959> network<00:02:54.350> is<00:02:54.500> going 00:02:54.820 --> 00:02:54.830 align:start position:0% transactions then the network is going 00:02:54.830 --> 00:02:58.120 align:start position:0% transactions then the network is going to<00:02:54.950> be<00:02:55.040> centralized<00:02:55.550> and<00:02:55.820> last<00:02:56.660> the<00:02:57.470> actual 00:02:58.120 --> 00:02:58.130 align:start position:0% to be centralized and last the actual 00:02:58.130 --> 00:03:01.000 align:start position:0% to be centralized and last the actual full<00:02:58.550> node<00:02:58.820> topology<00:02:59.540> is<00:02:59.780> very<00:03:00.320> important<00:03:00.770> if 00:03:01.000 --> 00:03:01.010 align:start position:0% full node topology is very important if 00:03:01.010 --> 00:03:03.040 align:start position:0% full node topology is very important if I<00:03:01.160> take<00:03:01.370> a<00:03:01.400> node<00:03:01.670> out<00:03:01.880> and<00:03:02.209> then<00:03:02.420> the<00:03:02.600> network's 00:03:03.040 --> 00:03:03.050 align:start position:0% I take a node out and then the network's 00:03:03.050 --> 00:03:05.410 align:start position:0% I take a node out and then the network's disrupt<00:03:03.680> or<00:03:03.980> disconnect<00:03:04.520> then<00:03:05.060> of<00:03:05.180> course 00:03:05.410 --> 00:03:05.420 align:start position:0% disrupt or disconnect then of course 00:03:05.420 --> 00:03:07.860 align:start position:0% disrupt or disconnect then of course this<00:03:05.600> is<00:03:05.720> not<00:03:05.930> a<00:03:05.959> good<00:03:06.230> decentralized<00:03:06.800> network 00:03:07.860 --> 00:03:07.870 align:start position:0% this is not a good decentralized network 00:03:07.870 --> 00:03:10.990 align:start position:0% this is not a good decentralized network but<00:03:08.870> we<00:03:09.050> can<00:03:09.200> see<00:03:09.410> that<00:03:09.620> in<00:03:09.860> all<00:03:10.100> kind<00:03:10.610> of<00:03:10.730> ways 00:03:10.990 --> 00:03:11.000 align:start position:0% but we can see that in all kind of ways 00:03:11.000 --> 00:03:12.340 align:start position:0% but we can see that in all kind of ways that<00:03:11.209> we<00:03:11.270> can<00:03:11.480> improve<00:03:11.810> the<00:03:11.959> centralization 00:03:12.340 --> 00:03:12.350 align:start position:0% that we can improve the centralization 00:03:12.350 --> 00:03:14.740 align:start position:0% that we can improve the centralization it's<00:03:12.980> very<00:03:13.430> very<00:03:13.700> important<00:03:14.209> to<00:03:14.240> have<00:03:14.480> full 00:03:14.740 --> 00:03:14.750 align:start position:0% it's very very important to have full 00:03:14.750 --> 00:03:16.870 align:start position:0% it's very very important to have full nodes<00:03:14.990> we<00:03:15.170> cannot<00:03:15.560> live<00:03:15.950> without<00:03:16.160> full<00:03:16.640> nodes 00:03:16.870 --> 00:03:16.880 align:start position:0% nodes we cannot live without full nodes 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--> 00:03:28.030 align:start position:0% does a lot of services to the network it broadcasts<00:03:25.220> blocks<00:03:26.200> transactions<00:03:27.200> it<00:03:27.800> also 00:03:28.030 --> 00:03:28.040 align:start position:0% broadcasts blocks transactions it also 00:03:28.040 --> 00:03:32.140 align:start position:0% broadcasts blocks transactions it also hides<00:03:28.820> the<00:03:29.030> notes<00:03:29.989> IP<00:03:30.320> so<00:03:31.010> we<00:03:31.550> don't<00:03:31.790> give<00:03:32.030> an 00:03:32.140 --> 00:03:32.150 align:start position:0% hides the notes IP so we don't give an 00:03:32.150 --> 00:03:33.880 align:start position:0% hides the notes IP so we don't give an attacker<00:03:32.450> the<00:03:32.690> possibility<00:03:33.170> to<00:03:33.290> gather<00:03:33.590> all 00:03:33.880 --> 00:03:33.890 align:start position:0% attacker the possibility to gather all 00:03:33.890 --> 00:03:36.180 align:start position:0% attacker the possibility to gather all information<00:03:33.920> about<00:03:34.700> the<00:03:34.820> network<00:03:35.150> and<00:03:35.360> do 00:03:36.180 --> 00:03:36.190 align:start position:0% information about the network and do 00:03:36.190 --> 00:03:38.259 align:start position:0% information about the network and do partition<00:03:37.190> attack<00:03:37.489> source<00:03:37.850> denial<00:03:38.180> of 00:03:38.259 --> 00:03:38.269 align:start position:0% partition attack source denial of 00:03:38.269 --> 00:03:41.380 align:start position:0% partition attack source denial of service<00:03:38.630> attacks<00:03:38.959> also<00:03:39.739> a<00:03:40.430> node<00:03:40.850> provides 00:03:41.380 --> 00:03:41.390 align:start position:0% service attacks also a node provides 00:03:41.390 --> 00:03:45.009 align:start position:0% service attacks also a node provides filtering<00:03:42.700> services<00:03:43.700> for<00:03:44.000> light<00:03:44.239> clients<00:03:44.840> and 00:03:45.009 --> 00:03:45.019 align:start position:0% filtering services for light clients and 00:03:45.019 --> 00:03:47.259 align:start position:0% filtering services for light clients and of<00:03:45.500> course<00:03:45.769> the<00:03:46.040> most<00:03:46.190> important<00:03:46.730> function<00:03:47.090> it 00:03:47.259 --> 00:03:47.269 align:start position:0% of course the most important function it 00:03:47.269 --> 00:03:50.290 align:start position:0% of course the most important function it has<00:03:47.330> a<00:03:47.690> copy<00:03:48.140> of<00:03:48.440> the<00:03:48.950> state<00:03:49.280> and<00:03:49.580> the 00:03:50.290 --> 00:03:50.300 align:start position:0% has a copy of the state and the 00:03:50.300 --> 00:03:52.540 align:start position:0% has a copy of the state and the blockchain<00:03:50.600> to<00:03:51.050> serve<00:03:51.320> to<00:03:51.620> new<00:03:51.769> nodes<00:03:52.010> that 00:03:52.540 --> 00:03:52.550 align:start position:0% blockchain to serve to new nodes that 00:03:52.550 --> 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align:start position:0% to run a full node currently there are not<00:04:02.480> okay 00:04:03.310 --> 00:04:03.320 align:start position:0% not okay 00:04:03.320 --> 00:04:06.400 align:start position:0% not okay so<00:04:03.709> currently<00:04:04.459> is<00:04:04.580> quite<00:04:05.090> cheap<00:04:05.360> so<00:04:05.870> we<00:04:06.050> do<00:04:06.260> it 00:04:06.400 --> 00:04:06.410 align:start position:0% so currently is quite cheap so we do it 00:04:06.410 --> 00:04:08.500 align:start position:0% so currently is quite cheap so we do it but<00:04:06.800> in<00:04:06.950> the<00:04:07.040> future<00:04:07.310> we<00:04:07.459> don't<00:04:07.610> know<00:04:07.760> so 00:04:08.500 --> 00:04:08.510 align:start position:0% but in the future we don't know so 00:04:08.510 --> 00:04:10.930 align:start position:0% but in the future we don't know so anything<00:04:09.200> we<00:04:09.410> can<00:04:09.590> do<00:04:09.800> to<00:04:10.040> reward<00:04:10.220> full<00:04:10.670> nodes 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simple ways but most of them do not work 00:04:21.260 --> 00:04:23.620 align:start position:0% simple ways but most of them do not work for<00:04:21.650> instance<00:04:22.430> we<00:04:22.610> can<00:04:22.820> create<00:04:23.060> peer-to-peer 00:04:23.620 --> 00:04:23.630 align:start position:0% for instance we can create peer-to-peer 00:04:23.630 --> 00:04:26.680 align:start position:0% for instance we can create peer-to-peer pair<00:04:24.229> space<00:04:24.740> services<00:04:25.310> like<00:04:25.550> creating<00:04:26.510> a 00:04:26.680 --> 00:04:26.690 align:start position:0% pair space services like creating a 00:04:26.690 --> 00:04:28.480 align:start position:0% pair space services like creating a micro<00:04:27.260> channel<00:04:27.650> for 00:04:28.480 --> 00:04:28.490 align:start position:0% micro channel for 00:04:28.490 --> 00:04:31.740 align:start position:0% micro channel for one<00:04:28.789> no<00:04:29.030> to<00:04:29.090> appear<00:04:29.660> then<00:04:30.289> I<00:04:30.560> can<00:04:30.710> easy<00:04:30.889> or 00:04:31.740 --> 00:04:31.750 align:start position:0% one no to appear then I can easy or 00:04:31.750 --> 00:04:34.029 align:start position:0% one no to appear then I can easy or probabilistic<00:04:32.750> payment<00:04:33.350> which<00:04:33.530> also<00:04:33.800> works 00:04:34.029 --> 00:04:34.039 align:start position:0% probabilistic payment which also works 00:04:34.039 --> 00:04:36.939 align:start position:0% probabilistic payment which also works and<00:04:34.479> then<00:04:35.479> I<00:04:35.600> can't<00:04:35.870> just<00:04:36.169> ask<00:04:36.350> for<00:04:36.710> a<00:04:36.740> block 00:04:36.939 --> 00:04:36.949 align:start position:0% and then I can't just ask for a block 00:04:36.949 --> 00:04:38.860 align:start position:0% and then I can't just ask for a block and<00:04:37.280> then<00:04:37.789> you<00:04:37.910> give<00:04:38.090> me<00:04:38.180> the<00:04:38.300> block<00:04:38.509> I<00:04:38.690> make 00:04:38.860 --> 00:04:38.870 align:start position:0% and then you give me the block I make 00:04:38.870 --> 00:04:41.320 align:start position:0% and then you give me the block I make you<00:04:39.020> as<00:04:39.110> very<00:04:39.289> small<00:04:39.470> maker<00:04:39.830> payment<00:04:40.310> well<00:04:41.060> the 00:04:41.320 --> 00:04:41.330 align:start position:0% you as very small maker payment well the 00:04:41.330 --> 00:04:43.089 align:start position:0% you as very small maker payment well the problem<00:04:41.720> with<00:04:41.870> this<00:04:42.020> setup<00:04:42.349> is<00:04:42.680> of<00:04:42.889> course 00:04:43.089 --> 00:04:43.099 align:start position:0% problem with this setup is of course 00:04:43.099 --> 00:04:45.070 align:start position:0% problem with this setup is of course that<00:04:43.310> we<00:04:43.490> can<00:04:43.639> have<00:04:43.819> proxy<00:04:44.180> nodes<00:04:44.360> and<00:04:44.599> proxy 00:04:45.070 --> 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position:0% node and so they just are there to you 00:04:53.330 --> 00:04:55.480 align:start position:0% node and so they just are there to you know<00:04:53.389> they<00:04:54.110> don't<00:04:54.410> know<00:04:54.620> contribute<00:04:55.250> to<00:04:55.370> the 00:04:55.480 --> 00:04:55.490 align:start position:0% know they don't know contribute to the 00:04:55.490 --> 00:04:57.150 align:start position:0% know they don't know contribute to the centralization<00:04:55.849> it<00:04:56.270> just<00:04:56.509> make<00:04:56.690> the<00:04:56.840> network 00:04:57.150 --> 00:04:57.160 align:start position:0% centralization it just make the network 00:04:57.160 --> 00:05:01.450 align:start position:0% centralization it just make the network be<00:04:58.300> more<00:04:59.300> expensive<00:05:00.190> some<00:05:01.190> other 00:05:01.450 --> 00:05:01.460 align:start position:0% be more expensive some other 00:05:01.460 --> 00:05:04.060 align:start position:0% be more expensive some other cryptocurrencies<00:05:02.120> and<00:05:02.780> other<00:05:02.990> networks<00:05:03.470> rely 00:05:04.060 --> 00:05:04.070 align:start position:0% cryptocurrencies and other networks rely 00:05:04.070 --> 00:05:05.980 align:start position:0% cryptocurrencies and other networks rely on<00:05:04.099> some<00:05:04.669> calls<00:05:04.880> something<00:05:05.180> called<00:05:05.509> master 00:05:05.980 --> 00:05:05.990 align:start position:0% on some calls something called master 00:05:05.990 --> 00:05:09.520 align:start position:0% on some calls something called master node<00:05:06.199> of<00:05:06.620> course<00:05:07.220> this<00:05:07.610> master<00:05:08.000> node<00:05:08.530> regulary 00:05:09.520 --> 00:05:09.530 align:start position:0% node of course this master node regulary 00:05:09.530 --> 00:05:12.939 align:start position:0% node of course this master node regulary ping<00:05:09.889> nodes<00:05:10.490> so<00:05:10.910> they<00:05:11.150> can<00:05:11.360> vote<00:05:11.680> so<00:05:12.680> which 00:05:12.939 --> 00:05:12.949 align:start position:0% ping nodes so they can vote so which 00:05:12.949 --> 00:05:15.990 align:start position:0% ping nodes so they can vote so which nodes<00:05:13.250> have<00:05:13.490> to<00:05:13.610> be<00:05:13.729> rewarded<00:05:14.210> this<00:05:14.960> of<00:05:15.229> course 00:05:15.990 --> 00:05:16.000 align:start position:0% nodes have to be rewarded this of course 00:05:16.000 --> 00:05:18.010 align:start position:0% nodes have to be rewarded this of course has<00:05:17.000> a<00:05:17.030> lot<00:05:17.180> of<00:05:17.360> problems<00:05:17.810> with 00:05:18.010 --> 00:05:18.020 align:start position:0% has a lot of problems with 00:05:18.020 --> 00:05:19.570 align:start position:0% has a lot of problems with centralization<00:05:18.889> these<00:05:19.190> nodes<00:05:19.460> are 00:05:19.570 --> 00:05:19.580 align:start position:0% centralization these nodes are 00:05:19.580 --> 00:05:21.520 align:start position:0% centralization these nodes are centralized<00:05:20.060> and<00:05:20.300> also<00:05:20.840> these<00:05:21.020> nodes 00:05:21.520 --> 00:05:21.530 align:start position:0% centralized and also these nodes 00:05:21.530 --> 00:05:23.680 align:start position:0% centralized and also these nodes gather<00:05:21.740> a<00:05:21.830> lot<00:05:22.159> of<00:05:22.190> information<00:05:22.400> about<00:05:22.970> the<00:05:23.659> I 00:05:23.680 --> 00:05:23.690 align:start position:0% gather a lot of information about the I 00:05:23.690 --> 00:05:25.390 align:start position:0% gather a lot of information about the I piece<00:05:24.020> of<00:05:24.199> the<00:05:24.289> nodes<00:05:24.500> which<00:05:24.830> is<00:05:24.979> something<00:05:25.159> we 00:05:25.390 --> 00:05:25.400 align:start position:0% piece of the nodes which is something we 00:05:25.400 --> 00:05:29.020 align:start position:0% piece of the nodes which is something we want<00:05:25.639> to<00:05:25.699> avoid<00:05:26.800> so<00:05:27.800> I<00:05:27.830> will<00:05:28.250> present<00:05:28.430> a<00:05:28.759> third 00:05:29.020 --> 00:05:29.030 align:start position:0% want to avoid so I will present a third 00:05:29.030 --> 00:05:30.999 align:start position:0% want to avoid so I will present a third way<00:05:29.300> of<00:05:29.330> doing<00:05:29.750> this<00:05:29.900> and<00:05:30.080> the<00:05:30.169> interesting 00:05:30.999 --> 00:05:31.009 align:start position:0% way of doing this and the interesting 00:05:31.009 --> 00:05:32.860 align:start position:0% way of doing this and the interesting thing<00:05:31.190> is<00:05:31.340> that<00:05:31.370> this<00:05:31.819> is<00:05:31.880> a<00:05:32.030> communication 00:05:32.860 --> 00:05:32.870 align:start position:0% thing is that this is a communication 00:05:32.870 --> 00:05:35.050 align:start position:0% thing is that this is a communication between<00:05:33.349> smart<00:05:33.889> contracts<00:05:34.400> and<00:05:34.639> full<00:05:34.820> nodes 00:05:35.050 --> 00:05:35.060 align:start position:0% between smart contracts and full nodes 00:05:35.060 --> 00:05:38.560 align:start position:0% between smart contracts and full nodes without<00:05:35.780> any<00:05:36.139> other<00:05:36.409> user<00:05:37.190> or<00:05:37.610> external 00:05:38.560 --> 00:05:38.570 align:start position:0% without any other user or external 00:05:38.570 --> 00:05:41.379 align:start position:0% without any other user or external system<00:05:38.900> intervention<00:05:39.530> so<00:05:40.099> basically<00:05:40.789> there 00:05:41.379 --> 00:05:41.389 align:start position:0% system intervention so basically there 00:05:41.389 --> 00:05:43.089 align:start position:0% system intervention so basically there is<00:05:41.419> a<00:05:41.509> smart<00:05:41.840> contract<00:05:42.320> that<00:05:42.590> will<00:05:42.830> say 00:05:43.089 --> 00:05:43.099 align:start position:0% is a smart contract that will say 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store in your own house hard disk<00:05:50.150> a<00:05:50.479> copy<00:05:50.900> of<00:05:51.050> the<00:05:51.169> blockchain<00:05:51.380> okay<00:05:52.280> or 00:05:53.040 --> 00:05:53.050 align:start position:0% disk a copy of the blockchain okay or 00:05:53.050 --> 00:05:55.839 align:start position:0% disk a copy of the blockchain okay or that<00:05:54.050> you<00:05:54.259> are<00:05:54.289> so<00:05:54.500> irrational<00:05:55.219> that<00:05:55.460> you<00:05:55.789> are 00:05:55.839 --> 00:05:55.849 align:start position:0% that you are so irrational that you are 00:05:55.849 --> 00:05:58.810 align:start position:0% that you are so irrational that you are willing<00:05:56.150> to<00:05:56.449> buy<00:05:57.020> a<00:05:57.050> lot<00:05:57.349> of<00:05:57.380> hardware<00:05:57.889> just<00:05:58.099> to 00:05:58.810 --> 00:05:58.820 align:start position:0% willing to buy a lot of hardware just to 00:05:58.820 --> 00:06:01.029 align:start position:0% willing to buy a lot of hardware just to fake<00:05:59.030> this<00:05:59.180> proof<00:05:59.479> but<00:06:00.139> you<00:06:00.169> will<00:06:00.440> spend<00:06:00.710> more 00:06:01.029 --> 00:06:01.039 align:start position:0% fake this proof but you will spend more 00:06:01.039 --> 00:06:03.610 align:start position:0% fake this proof but you will spend more more<00:06:01.699> money<00:06:01.940> than<00:06:02.389> just<00:06:02.419> buying<00:06:03.020> the<00:06:03.229> hardest 00:06:03.610 --> 00:06:03.620 align:start position:0% more money than just buying the hardest 00:06:03.620 --> 00:06:06.010 align:start position:0% more money than just buying the hardest to<00:06:03.860> store<00:06:04.039> the<00:06:04.130> file<00:06:04.310> ok<00:06:05.000> and<00:06:05.210> I<00:06:05.539> will<00:06:05.750> tell<00:06:05.990> you 00:06:06.010 --> 00:06:06.020 align:start position:0% to store the file ok and I will tell you 00:06:06.020 --> 00:06:09.540 align:start position:0% to store the file ok and I will tell you if<00:06:06.469> nobody<00:06:07.130> else<00:06:07.479> finds<00:06:08.479> that<00:06:08.750> you<00:06:08.810> have<00:06:09.050> cheat 00:06:09.540 --> 00:06:09.550 align:start position:0% if nobody else finds that you have cheat 00:06:09.550 --> 00:06:13.719 align:start position:0% if nobody else finds that you have cheat so<00:06:10.550> if<00:06:11.090> the<00:06:11.810> fool<00:06:11.990> node<00:06:12.199> a<00:06:12.380> submits<00:06:13.039> a<00:06:13.190> proof<00:06:13.430> in 00:06:13.719 --> 00:06:13.729 align:start position:0% so if the fool node a submits a proof in 00:06:13.729 --> 00:06:16.270 align:start position:0% so if the fool node a submits a proof in transaction<00:06:14.300> data<00:06:14.539> then<00:06:15.259> an<00:06:15.530> our<00:06:15.650> full<00:06:16.070> node 00:06:16.270 --> 00:06:16.280 align:start position:0% transaction data then an our full node 00:06:16.280 --> 00:06:18.249 align:start position:0% transaction data then an our full node can<00:06:16.490> come<00:06:16.699> as<00:06:16.849> you<00:06:16.940> know<00:06:17.120> this<00:06:17.419> proof<00:06:17.780> is<00:06:17.960> fake 00:06:18.249 --> 00:06:18.259 align:start position:0% can come as you know this proof is fake 00:06:18.259 --> 00:06:21.730 align:start position:0% can come as you know this proof is fake and<00:06:18.590> the<00:06:19.370> smart<00:06:19.669> contract<00:06:20.120> can<00:06:20.659> evaluate<00:06:21.440> this 00:06:21.730 --> 00:06:21.740 align:start position:0% and the smart contract can evaluate this 00:06:21.740 --> 00:06:24.459 align:start position:0% and the smart contract can evaluate this proof<00:06:21.979> this<00:06:22.219> proof<00:06:22.430> must<00:06:22.639> be<00:06:23.199> able<00:06:24.199> to<00:06:24.380> be 00:06:24.459 --> 00:06:24.469 align:start position:0% proof this proof must be able to be 00:06:24.469 --> 00:06:26.560 align:start position:0% proof this proof must be able to be evaluated<00:06:25.130> with<00:06:25.310> very<00:06:25.550> low<00:06:25.820> amount<00:06:26.150> of<00:06:26.300> gas 00:06:26.560 --> 00:06:26.570 align:start position:0% evaluated with very low amount of gas 00:06:26.570 --> 00:06:30.159 align:start position:0% evaluated with very low amount of gas and<00:06:27.159> can<00:06:28.159> keep<00:06:28.460> a<00:06:28.639> pretty<00:06:28.820> posit<00:06:29.300> it's<00:06:29.900> per 00:06:30.159 --> 00:06:30.169 align:start position:0% and can keep a pretty posit it's per 00:06:30.169 --> 00:06:32.800 align:start position:0% and can keep a pretty posit it's per deposit<00:06:30.620> and<00:06:30.800> reward<00:06:31.190> be<00:06:31.610> for<00:06:31.940> providing<00:06:32.570> that 00:06:32.800 --> 00:06:32.810 align:start position:0% deposit and reward be for providing that 00:06:32.810 --> 00:06:38.500 align:start position:0% deposit and reward be for providing that useful<00:06:33.110> information<00:06:34.509> so<00:06:35.509> in<00:06:36.669> to<00:06:37.669> summarize<00:06:38.000> we 00:06:38.500 --> 00:06:38.510 align:start position:0% useful information so in to summarize we 00:06:38.510 --> 00:06:41.140 align:start position:0% useful information so in to summarize we want<00:06:38.810> a<00:06:39.020> node<00:06:39.560> to<00:06:39.949> be<00:06:40.039> able<00:06:40.159> to<00:06:40.310> prove<00:06:40.669> to<00:06:40.880> all 00:06:41.140 --> 00:06:41.150 align:start position:0% want a node to be able to prove to all 00:06:41.150 --> 00:06:42.350 align:start position:0% want a node to be able to prove to all remaining<00:06:41.630> nodes<00:06:41.960> in<00:06:42.169> the 00:06:42.350 --> 00:06:42.360 align:start position:0% remaining nodes in the 00:06:42.360 --> 00:06:43.850 align:start position:0% remaining nodes in the work<00:06:42.599> that<00:06:43.050> he<00:06:43.139> is<00:06:43.199> storing<00:06:43.560> the<00:06:43.650> blockchain 00:06:43.850 --> 00:06:43.860 align:start position:0% work that he is storing the blockchain 00:06:43.860 --> 00:06:47.209 align:start position:0% work that he is storing the blockchain okay<00:06:44.550> so<00:06:44.610> the<00:06:45.360> benefits<00:06:45.810> are<00:06:45.990> obvious<00:06:46.110> we<00:06:46.979> can 00:06:47.209 --> 00:06:47.219 align:start position:0% okay so the benefits are obvious we can 00:06:47.219 --> 00:06:50.779 align:start position:0% okay so the benefits are obvious we can detect<00:06:47.759> proxy<00:06:48.240> nodes<00:06:48.449> we<00:06:48.750> won't<00:06:49.439> pay<00:06:49.789> proxy 00:06:50.779 --> 00:06:50.789 align:start position:0% detect proxy nodes we won't pay proxy 00:06:50.789 --> 00:06:53.300 align:start position:0% detect proxy nodes we won't pay proxy nodes<00:06:51.000> and<00:06:51.240> we<00:06:52.199> don't<00:06:52.469> require<00:06:52.710> any<00:06:52.979> special 00:06:53.300 --> 00:06:53.310 align:start position:0% nodes and we don't require any special 00:06:53.310 --> 00:06:54.980 align:start position:0% nodes and we don't require any special change<00:06:53.789> to<00:06:53.969> the<00:06:54.120> network<00:06:54.449> for<00:06:54.479> the<00:06:54.750> nodes<00:06:54.900> that 00:06:54.980 --> 00:06:54.990 align:start position:0% change to the network for the nodes that 00:06:54.990 --> 00:06:58.790 align:start position:0% change to the network for the nodes that won't<00:06:55.349> want<00:06:55.979> to<00:06:56.039> participate<00:06:56.400> and<00:06:57.650> maybe<00:06:58.650> the 00:06:58.790 --> 00:06:58.800 align:start position:0% won't want to participate and maybe the 00:06:58.800 --> 00:07:00.800 align:start position:0% won't want to participate and maybe the drawback<00:06:59.280> is<00:06:59.460> that<00:06:59.789> we<00:07:00.270> are<00:07:00.419> not<00:07:00.659> actually 00:07:00.800 --> 00:07:00.810 align:start position:0% drawback is that we are not actually 00:07:00.810 --> 00:07:03.050 align:start position:0% drawback is that we are not actually proving<00:07:01.349> we<00:07:01.500> are<00:07:01.560> serving<00:07:02.099> the<00:07:02.189> blockchain<00:07:02.400> we 00:07:03.050 --> 00:07:03.060 align:start position:0% proving we are serving the blockchain we 00:07:03.060 --> 00:07:04.309 align:start position:0% proving we are serving the blockchain we are<00:07:03.180> proving<00:07:03.360> we<00:07:03.539> have<00:07:03.659> a<00:07:03.719> copy<00:07:03.990> of<00:07:04.199> the 00:07:04.309 --> 00:07:04.319 align:start position:0% are proving we have a copy of the 00:07:04.319 --> 00:07:06.140 align:start position:0% are proving we have a copy of the blockchain<00:07:04.500> but<00:07:05.129> since<00:07:05.370> we<00:07:05.520> have<00:07:05.729> a<00:07:05.759> copy<00:07:06.060> of 00:07:06.140 --> 00:07:06.150 align:start position:0% blockchain but since we have a copy of 00:07:06.150 --> 00:07:07.760 align:start position:0% blockchain but since we have a copy of the<00:07:06.300> blockchain<00:07:06.479> we<00:07:06.870> are<00:07:06.990> in<00:07:07.259> sync<00:07:07.560> with<00:07:07.680> the 00:07:07.760 --> 00:07:07.770 align:start position:0% the blockchain we are in sync with the 00:07:07.770 --> 00:07:10.399 align:start position:0% the blockchain we are in sync with the network<00:07:08.300> almost<00:07:09.300> sure<00:07:09.419> we<00:07:09.840> are<00:07:09.960> serving<00:07:10.319> it 00:07:10.399 --> 00:07:10.409 align:start position:0% network almost sure we are serving it 00:07:10.409 --> 00:07:13.330 align:start position:0% network almost sure we are serving it and<00:07:10.560> the<00:07:10.710> cost<00:07:10.889> of<00:07:11.069> serving<00:07:11.400> it<00:07:11.520> will<00:07:11.789> be<00:07:11.969> small 00:07:13.330 --> 00:07:13.340 align:start position:0% and the cost of serving it will be small 00:07:13.340 --> 00:07:16.969 align:start position:0% and the cost of serving it will be small so<00:07:14.340> to<00:07:14.969> to<00:07:15.750> manage<00:07:16.259> to<00:07:16.409> do<00:07:16.560> it 00:07:16.969 --> 00:07:16.979 align:start position:0% so to to manage to do it 00:07:16.979 --> 00:07:19.429 align:start position:0% so to to manage to do it we<00:07:17.250> are<00:07:17.669> need<00:07:18.360> we<00:07:18.569> need<00:07:18.719> some<00:07:19.110> cryptographic 00:07:19.429 --> 00:07:19.439 align:start position:0% we are need we need some cryptographic 00:07:19.439 --> 00:07:22.670 align:start position:0% we are need we need some cryptographic protocols<00:07:20.159> okay<00:07:20.400> so<00:07:20.759> these<00:07:21.000> are<00:07:21.060> the<00:07:21.680> previous 00:07:22.670 --> 00:07:22.680 align:start position:0% protocols okay so these are the previous 00:07:22.680 --> 00:07:25.670 align:start position:0% protocols okay so these are the previous attempts<00:07:23.490> to<00:07:23.969> do<00:07:24.360> this<00:07:24.870> kind<00:07:25.080> of<00:07:25.169> things<00:07:25.379> so<00:07:25.469> we 00:07:25.670 --> 00:07:25.680 align:start position:0% attempts to do this kind of things so we 00:07:25.680 --> 00:07:27.469 align:start position:0% attempts to do this kind of things so we have<00:07:25.710> provable<00:07:26.250> data<00:07:26.430> possession<00:07:26.939> which 00:07:27.469 --> 00:07:27.479 align:start position:0% have provable data possession which 00:07:27.479 --> 00:07:30.559 align:start position:0% have provable data possession which allows<00:07:27.840> you<00:07:28.080> a<00:07:28.729> verifier<00:07:29.729> to<00:07:30.000> send<00:07:30.180> some<00:07:30.360> data 00:07:30.559 --> 00:07:30.569 align:start position:0% allows you a verifier to send some data 00:07:30.569 --> 00:07:32.450 align:start position:0% allows you a verifier to send some data to<00:07:30.900> a<00:07:30.930> server<00:07:31.319> and<00:07:31.650> then<00:07:31.710> challenge<00:07:32.370> the 00:07:32.450 --> 00:07:32.460 align:start position:0% to a server and then challenge the 00:07:32.460 --> 00:07:34.399 align:start position:0% to a server and then challenge the server<00:07:32.669> to<00:07:32.909> see<00:07:33.060> if<00:07:33.150> this<00:07:33.330> data<00:07:33.569> is<00:07:33.689> still 00:07:34.399 --> 00:07:34.409 align:start position:0% server to see if this data is still 00:07:34.409 --> 00:07:36.350 align:start position:0% server to see if this data is still there<00:07:34.490> also<00:07:35.490> we<00:07:35.580> have<00:07:35.729> proved<00:07:35.969> over<00:07:36.210> to 00:07:36.350 --> 00:07:36.360 align:start position:0% there also we have proved over to 00:07:36.360 --> 00:07:39.050 align:start position:0% there also we have proved over to ability<00:07:36.629> where<00:07:37.349> the<00:07:37.590> thing<00:07:37.800> very<00:07:38.069> fiery<00:07:38.819> can 00:07:39.050 --> 00:07:39.060 align:start position:0% ability where the thing very fiery can 00:07:39.060 --> 00:07:41.990 align:start position:0% ability where the thing very fiery can also<00:07:39.439> have<00:07:40.439> certain<00:07:40.710> assurance<00:07:41.520> that<00:07:41.729> you 00:07:41.990 --> 00:07:42.000 align:start position:0% also have certain assurance that you 00:07:42.000 --> 00:07:43.939 align:start position:0% also have certain assurance that you will<00:07:42.120> be<00:07:42.389> able<00:07:42.509> to<00:07:42.719> recover<00:07:43.169> this<00:07:43.379> information 00:07:43.939 --> 00:07:43.949 align:start position:0% will be able to recover this information 00:07:43.949 --> 00:07:47.240 align:start position:0% will be able to recover this information in<00:07:44.039> the<00:07:44.099> future<00:07:44.250> these<00:07:45.180> two<00:07:45.449> are<00:07:45.949> called<00:07:46.949> proof 00:07:47.240 --> 00:07:47.250 align:start position:0% in the future these two are called proof 00:07:47.250 --> 00:07:49.850 align:start position:0% in the future these two are called proof of<00:07:47.400> storage<00:07:47.849> so<00:07:48.629> I<00:07:48.659> will<00:07:49.020> present<00:07:49.199> a<00:07:49.440> protocol 00:07:49.850 --> 00:07:49.860 align:start position:0% of storage so I will present a protocol 00:07:49.860 --> 00:07:51.740 align:start position:0% of storage so I will present a protocol very<00:07:50.219> simple<00:07:50.580> protocol<00:07:51.000> which<00:07:51.210> is<00:07:51.360> I<00:07:51.509> called 00:07:51.740 --> 00:07:51.750 align:start position:0% very simple protocol which is I called 00:07:51.750 --> 00:07:54.409 align:start position:0% very simple protocol which is I called proof<00:07:52.409> of<00:07:52.589> unique<00:07:52.889> blockchain<00:07:53.250> storage<00:07:53.669> that 00:07:54.409 --> 00:07:54.419 align:start position:0% proof of unique blockchain storage that 00:07:54.419 --> 00:07:56.990 align:start position:0% proof of unique blockchain storage that it's<00:07:54.810> a<00:07:54.930> proof<00:07:55.139> of<00:07:55.259> storage<00:07:55.620> scheme<00:07:56.279> but<00:07:56.580> also 00:07:56.990 --> 00:07:57.000 align:start position:0% it's a proof of storage scheme but also 00:07:57.000 --> 00:07:59.629 align:start position:0% it's a proof of storage scheme but also allows<00:07:57.330> you<00:07:57.509> to<00:07:57.539> ensure<00:07:58.289> that<00:07:58.319> the<00:07:58.979> other 00:07:59.629 --> 00:07:59.639 align:start position:0% allows you to ensure that the other 00:07:59.639 --> 00:08:01.820 align:start position:0% allows you to ensure that the other party<00:08:00.180> the<00:08:00.210> server<00:08:00.509> has<00:08:00.779> an<00:08:00.900> actual<00:08:01.259> copy<00:08:01.529> of 00:08:01.820 --> 00:08:01.830 align:start position:0% party the server has an actual copy of 00:08:01.830 --> 00:08:05.240 align:start position:0% party the server has an actual copy of this<00:08:02.400> file<00:08:02.639> okay<00:08:03.300> so<00:08:03.839> it<00:08:04.229> means<00:08:04.440> that<00:08:04.650> this 00:08:05.240 --> 00:08:05.250 align:start position:0% this file okay so it means that this 00:08:05.250 --> 00:08:07.939 align:start position:0% this file okay so it means that this file<00:08:05.550> will<00:08:05.849> be<00:08:06.029> related<00:08:06.810> to<00:08:07.080> some<00:08:07.469> some 00:08:07.939 --> 00:08:07.949 align:start position:0% file will be related to some some 00:08:07.949 --> 00:08:10.820 align:start position:0% file will be related to some some identity<00:08:08.580> okay<00:08:09.240> so<00:08:09.659> the<00:08:10.020> same<00:08:10.169> file<00:08:10.409> cannot<00:08:10.710> be 00:08:10.820 --> 00:08:10.830 align:start position:0% identity okay so the same file cannot be 00:08:10.830 --> 00:08:13.070 align:start position:0% identity okay so the same file cannot be related<00:08:11.009> to<00:08:11.219> two<00:08:11.550> identities<00:08:12.060> so<00:08:12.779> it<00:08:12.930> is 00:08:13.070 --> 00:08:13.080 align:start position:0% related to two identities so it is 00:08:13.080 --> 00:08:15.619 align:start position:0% related to two identities so it is interesting<00:08:13.349> that<00:08:13.589> this<00:08:14.219> year<00:08:14.610> file<00:08:15.360> coin 00:08:15.619 --> 00:08:15.629 align:start position:0% interesting that this year file coin 00:08:15.629 --> 00:08:17.420 align:start position:0% interesting that this year file coin presented<00:08:16.199> as<00:08:16.319> very<00:08:16.349> similar<00:08:16.889> proof<00:08:17.219> that 00:08:17.420 --> 00:08:17.430 align:start position:0% presented as very similar proof that 00:08:17.430 --> 00:08:20.059 align:start position:0% presented as very similar proof that they<00:08:17.639> call<00:08:17.819> proof<00:08:18.029> of<00:08:18.180> replication<00:08:18.930> and<00:08:19.139> that 00:08:20.059 --> 00:08:20.069 align:start position:0% they call proof of replication and that 00:08:20.069 --> 00:08:22.519 align:start position:0% they call proof of replication and that I<00:08:20.099> also<00:08:20.879> publish<00:08:21.509> a<00:08:21.599> couple<00:08:21.719> of<00:08:21.930> years<00:08:22.020> ago<00:08:22.229> and 00:08:22.519 --> 00:08:22.529 align:start position:0% I also publish a couple of years ago and 00:08:22.529 --> 00:08:24.800 align:start position:0% I also publish a couple of years ago and it's<00:08:23.009> kind<00:08:23.849> of<00:08:23.939> the<00:08:24.060> same<00:08:24.210> idea<00:08:24.330> but<00:08:24.689> it's 00:08:24.800 --> 00:08:24.810 align:start position:0% it's kind of the same idea but it's 00:08:24.810 --> 00:08:28.429 align:start position:0% it's kind of the same idea but it's worse<00:08:25.379> and<00:08:25.800> I<00:08:26.490> will<00:08:26.729> tell<00:08:27.360> you<00:08:27.389> later<00:08:27.689> why<00:08:28.139> it 00:08:28.429 --> 00:08:28.439 align:start position:0% worse and I will tell you later why it 00:08:28.439 --> 00:08:33.259 align:start position:0% worse and I will tell you later why it has<00:08:28.789> many<00:08:29.789> problems<00:08:31.130> so<00:08:32.130> in<00:08:32.370> a<00:08:32.459> nutshell<00:08:32.640> we 00:08:33.259 --> 00:08:33.269 align:start position:0% has many problems so in a nutshell we 00:08:33.269 --> 00:08:34.670 align:start position:0% has many problems so in a nutshell we take<00:08:33.539> the<00:08:33.659> file<00:08:33.899> we<00:08:34.229> want<00:08:34.380> to<00:08:34.500> prove 00:08:34.670 --> 00:08:34.680 align:start position:0% take the file we want to prove 00:08:34.680 --> 00:08:37.579 align:start position:0% take the file we want to prove possession<00:08:35.250> and<00:08:35.430> we<00:08:36.329> will<00:08:36.539> encode<00:08:37.409> it 00:08:37.579 --> 00:08:37.589 align:start position:0% possession and we will encode it 00:08:37.589 --> 00:08:39.560 align:start position:0% possession and we will encode it together<00:08:37.979> with<00:08:38.219> an<00:08:38.370> identity<00:08:38.789> and<00:08:39.060> this 00:08:39.560 --> 00:08:39.570 align:start position:0% together with an identity and this 00:08:39.570 --> 00:08:42.529 align:start position:0% together with an identity and this identity<00:08:40.169> will<00:08:40.680> be<00:08:40.829> generally<00:08:41.399> your<00:08:41.789> node 00:08:42.529 --> 00:08:42.539 align:start position:0% identity will be generally your node 00:08:42.539 --> 00:08:45.560 align:start position:0% identity will be generally your node address<00:08:42.750> your<00:08:43.459> film<00:08:44.459> address<00:08:44.820> or<00:08:45.089> our<00:08:45.209> skater 00:08:45.560 --> 00:08:45.570 align:start position:0% address your film address or our skater 00:08:45.570 --> 00:08:48.530 align:start position:0% address your film address or our skater dress<00:08:45.630> so<00:08:46.560> what<00:08:47.130> we<00:08:47.279> need<00:08:47.459> is<00:08:47.490> as<00:08:47.730> decoding<00:08:48.300> is 00:08:48.530 --> 00:08:48.540 align:start position:0% dress so what we need is as decoding is 00:08:48.540 --> 00:08:51.290 align:start position:0% dress so what we need is as decoding is fast<00:08:48.990> but<00:08:49.800> it<00:08:50.070> should<00:08:50.310> only<00:08:50.459> be<00:08:50.730> fast<00:08:51.120> enough 00:08:51.290 --> 00:08:51.300 align:start position:0% fast but it should only be fast enough 00:08:51.300 --> 00:08:54.319 align:start position:0% fast but it should only be fast enough you<00:08:51.690> know<00:08:51.810> for<00:08:52.470> not<00:08:53.130> to<00:08:53.310> interfere<00:08:53.579> where<00:08:54.120> your 00:08:54.319 --> 00:08:54.329 align:start position:0% you know for not to interfere where your 00:08:54.329 --> 00:08:55.819 align:start position:0% you know for not to interfere where your network<00:08:54.510> operations 00:08:55.819 --> 00:08:55.829 align:start position:0% network operations 00:08:55.829 --> 00:08:58.519 align:start position:0% network operations on<00:08:56.550> the<00:08:56.730> contrary<00:08:56.999> appending<00:08:57.809> and<00:08:57.989> updating 00:08:58.519 --> 00:08:58.529 align:start position:0% on the contrary appending and updating 00:08:58.529 --> 00:09:01.189 align:start position:0% on the contrary appending and updating will<00:08:58.800> be<00:08:58.920> a<00:08:58.949> much<00:08:59.189> slower<00:08:59.779> operation<00:09:00.779> but 00:09:01.189 --> 00:09:01.199 align:start position:0% will be a much slower operation but 00:09:01.199 --> 00:09:03.530 align:start position:0% will be a much slower operation but again<00:09:01.470> not<00:09:01.920> slow<00:09:02.249> enough<00:09:02.429> to<00:09:02.850> interfere<00:09:03.329> with 00:09:03.530 --> 00:09:03.540 align:start position:0% again not slow enough to interfere with 00:09:03.540 --> 00:09:06.590 align:start position:0% again not slow enough to interfere with operations<00:09:04.290> the<00:09:05.160> property<00:09:05.699> is<00:09:05.910> that<00:09:06.149> when<00:09:06.480> you 00:09:06.590 --> 00:09:06.600 align:start position:0% operations the property is that when you 00:09:06.600 --> 00:09:09.139 align:start position:0% operations the property is that when you encode<00:09:06.929> the<00:09:07.110> file<00:09:07.379> and<00:09:07.709> you<00:09:08.339> encode<00:09:08.670> a<00:09:08.819> second 00:09:09.139 --> 00:09:09.149 align:start position:0% encode the file and you encode a second 00:09:09.149 --> 00:09:11.150 align:start position:0% encode the file and you encode a second file<00:09:09.329> there<00:09:09.569> is<00:09:09.660> nothing<00:09:10.079> to<00:09:10.199> share<00:09:10.410> in<00:09:10.889> these 00:09:11.150 --> 00:09:11.160 align:start position:0% file there is nothing to share in these 00:09:11.160 --> 00:09:15.199 align:start position:0% file there is nothing to share in these same<00:09:11.429> codings<00:09:11.959> so<00:09:12.959> the<00:09:13.589> server<00:09:13.889> will<00:09:14.879> engage 00:09:15.199 --> 00:09:15.209 align:start position:0% same codings so the server will engage 00:09:15.209 --> 00:09:17.389 align:start position:0% same codings so the server will engage in<00:09:15.420> a<00:09:15.480> challenge<00:09:15.869> response<00:09:16.079> protocol<00:09:16.739> with<00:09:17.369> a 00:09:17.389 --> 00:09:17.399 align:start position:0% in a challenge response protocol with a 00:09:17.399 --> 00:09:20.689 align:start position:0% in a challenge response protocol with a verifier<00:09:17.970> and<00:09:18.410> he<00:09:19.410> will<00:09:19.589> use<00:09:19.889> the<00:09:20.189> encoded 00:09:20.689 --> 00:09:20.699 align:start position:0% verifier and he will use the encoded 00:09:20.699 --> 00:09:22.460 align:start position:0% verifier and he will use the encoded data<00:09:20.730> not<00:09:21.209> the<00:09:21.269> uncut<00:09:21.629> decoded<00:09:22.049> data<00:09:22.230> but<00:09:22.439> just 00:09:22.460 --> 00:09:22.470 align:start position:0% data not the uncut decoded data but just 00:09:22.470 --> 00:09:25.039 align:start position:0% data not the uncut decoded data but just encoded<00:09:23.100> data<00:09:23.129> and<00:09:23.579> we'll<00:09:24.149> it<00:09:24.449> must<00:09:24.869> be 00:09:25.039 --> 00:09:25.049 align:start position:0% encoded data and we'll it must be 00:09:25.049 --> 00:09:27.710 align:start position:0% encoded data and we'll it must be irrational<00:09:25.920> from<00:09:26.879> the<00:09:26.999> economic<00:09:27.329> point<00:09:27.540> of 00:09:27.710 --> 00:09:27.720 align:start position:0% irrational from the economic point of 00:09:27.720 --> 00:09:31.400 align:start position:0% irrational from the economic point of view<00:09:27.779> to<00:09:28.379> do<00:09:28.529> anything<00:09:28.949> else<00:09:29.249> like<00:09:30.170> relate<00:09:31.170> to 00:09:31.400 --> 00:09:31.410 align:start position:0% view to do anything else like relate to 00:09:31.410 --> 00:09:32.840 align:start position:0% view to do anything else like relate to another<00:09:31.589> party<00:09:32.100> or<00:09:32.129> like<00:09:32.489> having<00:09:32.730> a 00:09:32.840 --> 00:09:32.850 align:start position:0% another party or like having a 00:09:32.850 --> 00:09:36.079 align:start position:0% another party or like having a supercomputer<00:09:33.269> or<00:09:33.600> whatever<00:09:34.579> so<00:09:35.579> this<00:09:35.819> is<00:09:35.939> how 00:09:36.079 --> 00:09:36.089 align:start position:0% supercomputer or whatever so this is how 00:09:36.089 --> 00:09:38.629 align:start position:0% supercomputer or whatever so this is how the<00:09:36.540> peer-to-peer<00:09:36.899> protocol<00:09:37.559> goes<00:09:37.829> without 00:09:38.629 --> 00:09:38.639 align:start position:0% the peer-to-peer protocol goes without 00:09:38.639 --> 00:09:40.669 align:start position:0% the peer-to-peer protocol goes without without<00:09:39.059> smart<00:09:39.389> contracts<00:09:39.869> so<00:09:40.019> there<00:09:40.559> is<00:09:40.649> a 00:09:40.669 --> 00:09:40.679 align:start position:0% without smart contracts so there is a 00:09:40.679 --> 00:09:43.100 align:start position:0% without smart contracts so there is a harness<00:09:41.009> verify<00:09:41.369> say<00:09:41.730> give<00:09:42.329> me<00:09:42.449> the<00:09:42.569> hash<00:09:42.749> of<00:09:42.899> n 00:09:43.100 --> 00:09:43.110 align:start position:0% harness verify say give me the hash of n 00:09:43.110 --> 00:09:46.609 align:start position:0% harness verify say give me the hash of n Cellular<00:09:43.980> randomly<00:09:44.429> selected<00:09:45.110> blocks<00:09:46.110> of<00:09:46.379> the 00:09:46.609 --> 00:09:46.619 align:start position:0% Cellular randomly selected blocks of the 00:09:46.619 --> 00:09:49.579 align:start position:0% Cellular randomly selected blocks of the file<00:09:46.860> and<00:09:47.179> that<00:09:48.179> had<00:09:48.509> been<00:09:48.720> encoded<00:09:49.019> with<00:09:49.410> your 00:09:49.579 --> 00:09:49.589 align:start position:0% file and that had been encoded with your 00:09:49.589 --> 00:09:51.829 align:start position:0% file and that had been encoded with your node<00:09:49.769> address<00:09:50.160> and<00:09:50.399> please<00:09:50.970> do<00:09:51.239> it<00:09:51.360> in<00:09:51.600> less 00:09:51.829 --> 00:09:51.839 align:start position:0% node address and please do it in less 00:09:51.839 --> 00:09:54.410 align:start position:0% node address and please do it in less than<00:09:51.989> one<00:09:52.139> second<00:09:52.559> so<00:09:53.040> the<00:09:53.489> consumer<00:09:54.119> has<00:09:54.389> the 00:09:54.410 --> 00:09:54.420 align:start position:0% than one second so the consumer has the 00:09:54.420 --> 00:09:56.780 align:start position:0% than one second so the consumer has the information<00:09:54.779> just<00:09:55.499> put<00:09:56.009> the<00:09:56.189> information<00:09:56.279> to 00:09:56.780 --> 00:09:56.790 align:start position:0% information just put the information to 00:09:56.790 --> 00:10:00.499 align:start position:0% information just put the information to memory<00:09:57.029> and<00:09:57.509> hash<00:09:57.809> it<00:09:57.989> and<00:09:58.199> it<00:09:58.589> works<00:09:59.179> now<00:10:00.179> if 00:10:00.499 --> 00:10:00.509 align:start position:0% memory and hash it and it works now if 00:10:00.509 --> 00:10:04.039 align:start position:0% memory and hash it and it works now if there<00:10:00.959> is<00:10:00.990> a<00:10:01.249> malicious<00:10:02.249> prover<00:10:02.670> he<00:10:03.509> can<00:10:03.689> think 00:10:04.039 --> 00:10:04.049 align:start position:0% there is a malicious prover he can think 00:10:04.049 --> 00:10:05.269 align:start position:0% there is a malicious prover he can think of<00:10:04.230> two<00:10:04.439> things<00:10:04.679> okay 00:10:05.269 --> 00:10:05.279 align:start position:0% of two things okay 00:10:05.279 --> 00:10:07.160 align:start position:0% of two things okay first<00:10:05.790> he<00:10:05.910> can<00:10:06.059> think<00:10:06.179> okay<00:10:06.480> I'm<00:10:06.600> gonna<00:10:06.779> relay 00:10:07.160 --> 00:10:07.170 align:start position:0% first he can think okay I'm gonna relay 00:10:07.170 --> 00:10:09.079 align:start position:0% first he can think okay I'm gonna relay the<00:10:07.410> same<00:10:07.740> query<00:10:08.129> the<00:10:08.369> same<00:10:08.549> challenge<00:10:08.970> to 00:10:09.079 --> 00:10:09.089 align:start position:0% the same query the same challenge to 00:10:09.089 --> 00:10:11.629 align:start position:0% the same query the same challenge to another<00:10:09.569> party<00:10:09.990> but<00:10:10.199> the<00:10:11.009> problem<00:10:11.429> is<00:10:11.490> that 00:10:11.629 --> 00:10:11.639 align:start position:0% another party but the problem is that 00:10:11.639 --> 00:10:13.400 align:start position:0% another party but the problem is that there<00:10:12.119> is<00:10:12.269> the<00:10:12.540> response<00:10:12.839> you<00:10:12.899> will<00:10:13.079> receive 00:10:13.400 --> 00:10:13.410 align:start position:0% there is the response you will receive 00:10:13.410 --> 00:10:16.129 align:start position:0% there is the response you will receive is<00:10:13.679> related<00:10:14.279> to<00:10:14.309> another<00:10:14.459> identity<00:10:15.269> so<00:10:15.809> he's 00:10:16.129 --> 00:10:16.139 align:start position:0% is related to another identity so he's 00:10:16.139 --> 00:10:17.780 align:start position:0% is related to another identity so he's not<00:10:16.379> going<00:10:16.559> to<00:10:16.619> get<00:10:16.799> paid<00:10:16.980> she's<00:10:17.220> just<00:10:17.399> going 00:10:17.780 --> 00:10:17.790 align:start position:0% not going to get paid she's just going 00:10:17.790 --> 00:10:20.809 align:start position:0% not going to get paid she's just going to<00:10:17.879> be<00:10:18.329> paying<00:10:18.839> another<00:10:19.139> party<00:10:19.589> if<00:10:20.129> he<00:10:20.189> wants 00:10:20.809 --> 00:10:20.819 align:start position:0% to be paying another party if he wants 00:10:20.819 --> 00:10:26.030 align:start position:0% to be paying another party if he wants to<00:10:22.129> redo<00:10:23.129> this<00:10:23.549> encoding<00:10:24.540> it<00:10:24.899> the<00:10:25.649> problem<00:10:25.980> is 00:10:26.030 --> 00:10:26.040 align:start position:0% to redo this encoding it the problem is 00:10:26.040 --> 00:10:27.949 align:start position:0% to redo this encoding it the problem is that<00:10:26.160> it<00:10:26.309> takes<00:10:26.399> a<00:10:26.699> lot<00:10:26.939> more<00:10:26.970> than<00:10:27.389> one<00:10:27.540> second 00:10:27.949 --> 00:10:27.959 align:start position:0% that it takes a lot more than one second 00:10:27.959 --> 00:10:31.160 align:start position:0% that it takes a lot more than one second okay<00:10:28.230> so<00:10:28.619> in<00:10:29.160> a<00:10:29.309> sense<00:10:29.519> he<00:10:29.699> cannot<00:10:29.970> fake<00:10:30.929> a 00:10:31.160 --> 00:10:31.170 align:start position:0% okay so in a sense he cannot fake a 00:10:31.170 --> 00:10:35.059 align:start position:0% okay so in a sense he cannot fake a proof<00:10:31.910> so<00:10:32.910> to<00:10:33.360> create<00:10:33.569> this<00:10:33.929> asymmetry<00:10:34.319> we<00:10:34.920> did 00:10:35.059 --> 00:10:35.069 align:start position:0% proof so to create this asymmetry we did 00:10:35.069 --> 00:10:37.069 align:start position:0% proof so to create this asymmetry we did we<00:10:35.369> need<00:10:35.519> something<00:10:35.850> I<00:10:35.970> call<00:10:36.209> practical<00:10:36.899> and 00:10:37.069 --> 00:10:37.079 align:start position:0% we need something I call practical and 00:10:37.079 --> 00:10:40.009 align:start position:0% we need something I call practical and symmetric<00:10:37.529> time<00:10:37.769> encoders<00:10:38.249> or<00:10:38.459> parties<00:10:38.910> so<00:10:39.569> we 00:10:40.009 --> 00:10:40.019 align:start position:0% symmetric time encoders or parties so we 00:10:40.019 --> 00:10:42.319 align:start position:0% symmetric time encoders or parties so we have<00:10:40.169> a<00:10:40.199> program<00:10:40.709> which<00:10:41.429> is<00:10:41.610> an<00:10:41.730> encoder<00:10:42.059> we 00:10:42.319 --> 00:10:42.329 align:start position:0% have a program which is an encoder we 00:10:42.329 --> 00:10:43.999 align:start position:0% have a program which is an encoder we have<00:10:42.509> another<00:10:42.720> program<00:10:43.019> which<00:10:43.439> is<00:10:43.559> a<00:10:43.589> decoder 00:10:43.999 --> 00:10:44.009 align:start position:0% have another program which is a decoder 00:10:44.009 --> 00:10:45.919 align:start position:0% have another program which is a decoder for<00:10:44.160> a<00:10:44.369> certain<00:10:44.699> Turing<00:10:44.939> machine<00:10:45.269> and<00:10:45.449> we 00:10:45.919 --> 00:10:45.929 align:start position:0% for a certain Turing machine and we 00:10:45.929 --> 00:10:48.470 align:start position:0% for a certain Turing machine and we define<00:10:46.259> the<00:10:46.529> steps<00:10:46.829> this<00:10:47.160> program<00:10:47.939> performs 00:10:48.470 --> 00:10:48.480 align:start position:0% define the steps this program performs 00:10:48.480 --> 00:10:51.949 align:start position:0% define the steps this program performs as<00:10:48.689> the<00:10:49.529> number<00:10:49.769> of<00:10:49.860> step<00:10:50.129> it<00:10:50.369> requires<00:10:50.819> to<00:10:51.329> run 00:10:51.949 --> 00:10:51.959 align:start position:0% as the number of step it requires to run 00:10:51.959 --> 00:10:56.299 align:start position:0% as the number of step it requires to run for<00:10:52.619> a<00:10:52.649> random<00:10:53.519> input<00:10:53.699> until<00:10:54.660> it<00:10:54.749> halts<00:10:55.169> and<00:10:56.069> we 00:10:56.299 --> 00:10:56.309 align:start position:0% for a random input until it halts and we 00:10:56.309 --> 00:10:59.059 align:start position:0% for a random input until it halts and we will<00:10:56.429> ask<00:10:56.610> that<00:10:56.790> this<00:10:57.470> steps<00:10:58.470> function<00:10:58.919> is 00:10:59.059 --> 00:10:59.069 align:start position:0% will ask that this steps function is 00:10:59.069 --> 00:11:02.960 align:start position:0% will ask that this steps function is mostly<00:10:59.879> uniform<00:11:00.480> so<00:11:01.049> with<00:11:01.739> we<00:11:02.129> we<00:11:02.489> said<00:11:02.759> that 00:11:02.960 --> 00:11:02.970 align:start position:0% mostly uniform so with we we said that 00:11:02.970 --> 00:11:05.090 align:start position:0% mostly uniform so with we we said that we<00:11:03.089> have<00:11:03.239> two<00:11:03.389> programs<00:11:03.600> and<00:11:04.019> we<00:11:04.649> said<00:11:04.889> that 00:11:05.090 --> 00:11:05.100 align:start position:0% we have two programs and we said that 00:11:05.100 --> 00:11:08.299 align:start position:0% we have two programs and we said that the<00:11:05.339> coding<00:11:05.959> if<00:11:06.959> you<00:11:07.199> if<00:11:07.379> i<00:11:07.499> encode<00:11:07.829> an<00:11:07.980> input 00:11:08.299 --> 00:11:08.309 align:start position:0% the coding if you if i encode an input 00:11:08.309 --> 00:11:09.560 align:start position:0% the coding if you if i encode an input and<00:11:08.459> I<00:11:08.669> decode<00:11:09.089> it<00:11:09.269> I 00:11:09.560 --> 00:11:09.570 align:start position:0% and I decode it I 00:11:09.570 --> 00:11:11.630 align:start position:0% and I decode it I the<00:11:09.720> same<00:11:09.870> input<00:11:10.200> so<00:11:10.770> we<00:11:11.190> define<00:11:11.490> the 00:11:11.630 --> 00:11:11.640 align:start position:0% the same input so we define the 00:11:11.640 --> 00:11:13.670 align:start position:0% the same input so we define the asymmetry<00:11:12.030> ratio<00:11:12.510> as<00:11:12.720> the<00:11:13.050> number<00:11:13.290> of<00:11:13.380> steps 00:11:13.670 --> 00:11:13.680 align:start position:0% asymmetry ratio as the number of steps 00:11:13.680 --> 00:11:16.490 align:start position:0% asymmetry ratio as the number of steps it<00:11:13.950> takes<00:11:14.130> to<00:11:14.370> the<00:11:14.580> code<00:11:14.790> divided<00:11:15.750> by<00:11:16.440> the 00:11:16.490 --> 00:11:16.500 align:start position:0% it takes to the code divided by the 00:11:16.500 --> 00:11:20.540 align:start position:0% it takes to the code divided by the number<00:11:16.770> of<00:11:16.920> steps<00:11:17.280> it<00:11:17.550> takes<00:11:17.850> to<00:11:18.090> encode<00:11:19.550> so 00:11:20.540 --> 00:11:20.550 align:start position:0% number of steps it takes to encode so 00:11:20.550 --> 00:11:22.940 align:start position:0% number of steps it takes to encode so the<00:11:20.850> desired<00:11:21.210> properties<00:11:21.870> at<00:11:22.080> of<00:11:22.470> course<00:11:22.650> the 00:11:22.940 --> 00:11:22.950 align:start position:0% the desired properties at of course the 00:11:22.950 --> 00:11:26.390 align:start position:0% the desired properties at of course the program<00:11:23.190> must<00:11:23.460> be<00:11:23.640> small<00:11:23.970> and<00:11:24.360> if<00:11:25.140> I<00:11:25.350> if<00:11:26.070> there 00:11:26.390 --> 00:11:26.400 align:start position:0% program must be small and if I if there 00:11:26.400 --> 00:11:30.320 align:start position:0% program must be small and if I if there is<00:11:26.490> any<00:11:26.820> other<00:11:27.350> party<00:11:28.490> that<00:11:29.490> encloses<00:11:30.030> a 00:11:30.320 --> 00:11:30.330 align:start position:0% is any other party that encloses a 00:11:30.330 --> 00:11:33.980 align:start position:0% is any other party that encloses a mapping<00:11:30.750> then<00:11:31.080> this<00:11:31.680> function<00:11:31.980> this<00:11:32.990> sorry 00:11:33.980 --> 00:11:33.990 align:start position:0% mapping then this function this sorry 00:11:33.990 --> 00:11:36.650 align:start position:0% mapping then this function this sorry this<00:11:34.140> encoding<00:11:34.560> must<00:11:35.190> be<00:11:35.370> relatively<00:11:36.090> equally 00:11:36.650 --> 00:11:36.660 align:start position:0% this encoding must be relatively equally 00:11:36.660 --> 00:11:39.560 align:start position:0% this encoding must be relatively equally efficient<00:11:37.140> efficient<00:11:37.950> okay<00:11:38.250> and<00:11:38.570> to 00:11:39.560 --> 00:11:39.570 align:start position:0% efficient efficient okay and to 00:11:39.570 --> 00:11:42.790 align:start position:0% efficient efficient okay and to guarentees<00:11:40.050> we<00:11:40.710> need<00:11:40.830> to<00:11:41.010> rely<00:11:41.220> on<00:11:41.250> some 00:11:42.790 --> 00:11:42.800 align:start position:0% guarentees we need to rely on some 00:11:42.800 --> 00:11:45.110 align:start position:0% guarentees we need to rely on some complexity<00:11:43.800> assumptions<00:11:44.310> or<00:11:44.580> number 00:11:45.110 --> 00:11:45.120 align:start position:0% complexity assumptions or number 00:11:45.120 --> 00:11:47.120 align:start position:0% complexity assumptions or number theoretic<00:11:45.360> assumptions<00:11:46.200> to<00:11:46.590> make<00:11:46.620> sure<00:11:46.920> that 00:11:47.120 --> 00:11:47.130 align:start position:0% theoretic assumptions to make sure that 00:11:47.130 --> 00:11:50.120 align:start position:0% theoretic assumptions to make sure that the<00:11:47.340> encoding<00:11:47.640> that<00:11:47.850> we<00:11:48.180> peek<00:11:48.420> is<00:11:48.810> one<00:11:49.800> of<00:11:49.980> the 00:11:50.120 --> 00:11:50.130 align:start position:0% the encoding that we peek is one of the 00:11:50.130 --> 00:11:52.490 align:start position:0% the encoding that we peek is one of the fastest<00:11:50.700> encoding<00:11:51.600> Possible's<00:11:52.200> for<00:11:52.350> that 00:11:52.490 --> 00:11:52.500 align:start position:0% fastest encoding Possible's for that 00:11:52.500 --> 00:11:55.910 align:start position:0% fastest encoding Possible's for that mapping<00:11:52.740> also<00:11:53.640> we<00:11:54.270> want<00:11:54.510> as<00:11:55.050> I<00:11:55.200> said<00:11:55.530> that<00:11:55.740> the 00:11:55.910 --> 00:11:55.920 align:start position:0% mapping also we want as I said that the 00:11:55.920 --> 00:11:58.780 align:start position:0% mapping also we want as I said that the coning<00:11:56.280> and<00:11:56.430> encoding<00:11:56.730> this<00:11:56.820> piece<00:11:57.030> will<00:11:57.450> be 00:11:58.780 --> 00:11:58.790 align:start position:0% coning and encoding this piece will be 00:11:58.790 --> 00:12:01.040 align:start position:0% coning and encoding this piece will be practical<00:11:59.790> for<00:11:59.940> our<00:11:59.970> application<00:12:00.630> and<00:12:00.780> we 00:12:01.040 --> 00:12:01.050 align:start position:0% practical for our application and we 00:12:01.050 --> 00:12:02.780 align:start position:0% practical for our application and we want<00:12:01.260> the<00:12:01.350> highest<00:12:01.710> possible<00:12:02.130> ask<00:12:02.310> me<00:12:02.490> to<00:12:02.610> rate 00:12:02.780 --> 00:12:02.790 align:start position:0% want the highest possible ask me to rate 00:12:02.790 --> 00:12:05.090 align:start position:0% want the highest possible ask me to rate you<00:12:02.970> because<00:12:03.540> that<00:12:03.570> is<00:12:03.810> going<00:12:04.290> to<00:12:04.470> protect<00:12:04.800> us 00:12:05.090 --> 00:12:05.100 align:start position:0% you because that is going to protect us 00:12:05.100 --> 00:12:07.010 align:start position:0% you because that is going to protect us from<00:12:05.160> the<00:12:05.460> attacker<00:12:05.880> trying<00:12:06.600> to<00:12:06.750> encode 00:12:07.010 --> 00:12:07.020 align:start position:0% from the attacker trying to encode 00:12:07.020 --> 00:12:10.220 align:start position:0% from the attacker trying to encode on-the-fly<00:12:08.240> well<00:12:09.240> there<00:12:09.600> is<00:12:09.690> a<00:12:09.720> function<00:12:10.200> that 00:12:10.220 --> 00:12:10.230 align:start position:0% on-the-fly well there is a function that 00:12:10.230 --> 00:12:13.040 align:start position:0% on-the-fly well there is a function that has<00:12:10.560> these<00:12:10.860> these<00:12:11.640> properties<00:12:12.180> it's<00:12:12.750> called 00:12:13.040 --> 00:12:13.050 align:start position:0% has these these properties it's called 00:12:13.050 --> 00:12:15.470 align:start position:0% has these these properties it's called the<00:12:13.200> pollak<00:12:13.590> Hellman<00:12:14.040> cipher<00:12:14.730> private<00:12:15.300> key 00:12:15.470 --> 00:12:15.480 align:start position:0% the pollak Hellman cipher private key 00:12:15.480 --> 00:12:17.750 align:start position:0% the pollak Hellman cipher private key cipher<00:12:15.900> is<00:12:16.020> a<00:12:16.050> very<00:12:16.500> very<00:12:16.800> old<00:12:17.010> one<00:12:17.490> of<00:12:17.670> the 00:12:17.750 --> 00:12:17.760 align:start position:0% cipher is a very very old one of the 00:12:17.760 --> 00:12:20.030 align:start position:0% cipher is a very very old one of the first<00:12:18.060> number<00:12:18.720> theoretic<00:12:19.040> encryption 00:12:20.030 --> 00:12:20.040 align:start position:0% first number theoretic encryption 00:12:20.040 --> 00:12:23.690 align:start position:0% first number theoretic encryption systems<00:12:20.460> it<00:12:21.090> works<00:12:21.420> like<00:12:21.720> this<00:12:21.900> -<00:12:22.470> well<00:12:23.460> in 00:12:23.690 --> 00:12:23.700 align:start position:0% systems it works like this - well in 00:12:23.700 --> 00:12:25.550 align:start position:0% systems it works like this - well in this<00:12:24.090> case<00:12:24.300> it's<00:12:24.540> the<00:12:24.630> opposite<00:12:24.990> decryption 00:12:25.550 --> 00:12:25.560 align:start position:0% this case it's the opposite decryption 00:12:25.560 --> 00:12:29.180 align:start position:0% this case it's the opposite decryption would<00:12:25.830> be<00:12:25.950> like<00:12:26.130> encoding<00:12:26.700> but<00:12:26.990> so<00:12:27.990> to<00:12:28.380> decode 00:12:29.180 --> 00:12:29.190 align:start position:0% would be like encoding but so to decode 00:12:29.190 --> 00:12:32.960 align:start position:0% would be like encoding but so to decode a<00:12:29.850> value<00:12:30.750> we<00:12:31.380> just<00:12:31.410> rise<00:12:32.310> it<00:12:32.550> to<00:12:32.580> the<00:12:32.760> third 00:12:32.960 --> 00:12:32.970 align:start position:0% a value we just rise it to the third 00:12:32.970 --> 00:12:36.860 align:start position:0% a value we just rise it to the third power<00:12:33.050> modulo<00:12:34.050> P<00:12:34.350> Prime<00:12:34.680> and<00:12:34.950> B<00:12:35.610> prime<00:12:35.820> and<00:12:36.150> to 00:12:36.860 --> 00:12:36.870 align:start position:0% power modulo P Prime and B prime and to 00:12:36.870 --> 00:12:40.010 align:start position:0% power modulo P Prime and B prime and to encode<00:12:37.230> it<00:12:37.560> we<00:12:37.920> will<00:12:38.070> raise<00:12:38.280> it<00:12:38.460> to<00:12:38.700> a<00:12:39.000> value<00:12:39.510> U 00:12:40.010 --> 00:12:40.020 align:start position:0% encode it we will raise it to a value U 00:12:40.020 --> 00:12:42.710 align:start position:0% encode it we will raise it to a value U which<00:12:40.560> has<00:12:40.770> approximately<00:12:41.040> and<00:12:41.610> bit<00:12:42.060> which<00:12:42.570> is 00:12:42.710 --> 00:12:42.720 align:start position:0% which has approximately and bit which is 00:12:42.720 --> 00:12:47.180 align:start position:0% which has approximately and bit which is the<00:12:43.050> inverse<00:12:43.350> of<00:12:43.710> the<00:12:45.140> three<00:12:46.140> models<00:12:46.530> P<00:12:46.920> minus 00:12:47.180 --> 00:12:47.190 align:start position:0% the inverse of the three models P minus 00:12:47.190 --> 00:12:49.820 align:start position:0% the inverse of the three models P minus one<00:12:47.400> so<00:12:47.940> we<00:12:48.270> get<00:12:48.420> this<00:12:48.630> encoding<00:12:49.290> the<00:12:49.500> coding 00:12:49.820 --> 00:12:49.830 align:start position:0% one so we get this encoding the coding 00:12:49.830 --> 00:12:52.610 align:start position:0% one so we get this encoding the coding property<00:12:50.280> so<00:12:50.940> using<00:12:51.630> the<00:12:51.750> standard<00:12:52.230> Square 00:12:52.610 --> 00:12:52.620 align:start position:0% property so using the standard Square 00:12:52.620 --> 00:12:55.190 align:start position:0% property so using the standard Square and<00:12:52.740> multiplayer<00:12:53.010> algorithm<00:12:54.080> encoding<00:12:55.080> will 00:12:55.190 --> 00:12:55.200 align:start position:0% and multiplayer algorithm encoding will 00:12:55.200 --> 00:13:01.430 align:start position:0% and multiplayer algorithm encoding will take<00:12:55.700> 1.5<00:12:57.320> times<00:12:58.320> n<00:12:58.790> multiplications<00:13:00.440> while 00:13:01.430 --> 00:13:01.440 align:start position:0% take 1.5 times n multiplications while 00:13:01.440 --> 00:13:02.780 align:start position:0% take 1.5 times n multiplications while the<00:13:01.680> coding<00:13:02.040> takes<00:13:02.340> only<00:13:02.520> three 00:13:02.780 --> 00:13:02.790 align:start position:0% the coding takes only three 00:13:02.790 --> 00:13:05.090 align:start position:0% the coding takes only three multiplications<00:13:03.150> so<00:13:03.690> the<00:13:04.260> asymmetry<00:13:04.620> ratio 00:13:05.090 --> 00:13:05.100 align:start position:0% multiplications so the asymmetry ratio 00:13:05.100 --> 00:13:07.610 align:start position:0% multiplications so the asymmetry ratio here<00:13:05.460> is<00:13:05.640> an<00:13:06.140> divided<00:13:07.140> by<00:13:07.230> 2 00:13:07.610 --> 00:13:07.620 align:start position:0% here is an divided by 2 00:13:07.620 --> 00:13:10.670 align:start position:0% here is an divided by 2 okay<00:13:08.190> so<00:13:08.280> we<00:13:08.550> can<00:13:08.700> make<00:13:09.060> this<00:13:09.270> asymmetry<00:13:09.930> ratio 00:13:10.670 --> 00:13:10.680 align:start position:0% okay so we can make this asymmetry ratio 00:13:10.680 --> 00:13:14.780 align:start position:0% okay so we can make this asymmetry ratio as<00:13:10.920> as<00:13:11.190> large<00:13:12.000> as<00:13:12.210> we<00:13:12.240> want<00:13:12.660> just<00:13:13.440> by<00:13:13.650> taking<00:13:14.280> a 00:13:14.780 --> 00:13:14.790 align:start position:0% as as large as we want just by taking a 00:13:14.790 --> 00:13:19.250 align:start position:0% as as large as we want just by taking a prime<00:13:15.540> which<00:13:15.960> is<00:13:15.990> you<00:13:16.530> know<00:13:16.650> larger<00:13:17.870> so<00:13:18.870> what 00:13:19.250 --> 00:13:19.260 align:start position:0% prime which is you know larger so what 00:13:19.260 --> 00:13:20.780 align:start position:0% prime which is you know larger so what are<00:13:19.380> the<00:13:19.530> practical<00:13:19.920> parameters<00:13:20.460> that<00:13:20.610> we<00:13:20.760> can 00:13:20.780 --> 00:13:20.790 align:start position:0% are the practical parameters that we can 00:13:20.790 --> 00:13:22.290 align:start position:0% are the practical parameters that we can choose<00:13:21.150> that<00:13:21.210> serve 00:13:22.290 --> 00:13:22.300 align:start position:0% choose that serve 00:13:22.300 --> 00:13:25.050 align:start position:0% choose that serve this<00:13:22.870> purpose<00:13:23.290> okay<00:13:23.860> I<00:13:24.040> tested<00:13:24.610> it<00:13:24.700> in<00:13:24.970> my 00:13:25.050 --> 00:13:25.060 align:start position:0% this purpose okay I tested it in my 00:13:25.060 --> 00:13:29.090 align:start position:0% this purpose okay I tested it in my laptop<00:13:25.570> with<00:13:25.840> a<00:13:25.870> lib<00:13:26.110> GMP<00:13:26.700> so<00:13:27.700> for<00:13:28.270> N<00:13:28.480> equals 00:13:29.090 --> 00:13:29.100 align:start position:0% laptop with a lib GMP so for N equals 00:13:29.100 --> 00:13:31.230 align:start position:0% laptop with a lib GMP so for N equals 2048<00:13:30.100> this<00:13:30.370> is<00:13:30.490> a<00:13:30.520> bit<00:13:30.700> little<00:13:30.940> bit<00:13:31.000> technical 00:13:31.230 --> 00:13:31.240 align:start position:0% 2048 this is a bit little bit technical 00:13:31.240 --> 00:13:33.450 align:start position:0% 2048 this is a bit little bit technical but<00:13:31.890> please<00:13:32.890> follow<00:13:33.100> me 00:13:33.450 --> 00:13:33.460 align:start position:0% but please follow me 00:13:33.460 --> 00:13:36.000 align:start position:0% but please follow me exponentiation<00:13:34.360> takes<00:13:34.840> two<00:13:35.650> point<00:13:35.860> eight 00:13:36.000 --> 00:13:36.010 align:start position:0% exponentiation takes two point eight 00:13:36.010 --> 00:13:38.220 align:start position:0% exponentiation takes two point eight milliseconds<00:13:36.970> while<00:13:37.210> three<00:13:37.600> multiplication 00:13:38.220 --> 00:13:38.230 align:start position:0% milliseconds while three multiplication 00:13:38.230 --> 00:13:43.140 align:start position:0% milliseconds while three multiplication takes<00:13:38.470> only<00:13:39.300> 3.6<00:13:40.470> microseconds<00:13:41.470> so<00:13:42.150> the 00:13:43.140 --> 00:13:43.150 align:start position:0% takes only 3.6 microseconds so the 00:13:43.150 --> 00:13:45.390 align:start position:0% takes only 3.6 microseconds so the theoretical<00:13:43.770> asymmetry<00:13:44.770> ratio<00:13:45.250> is 00:13:45.390 --> 00:13:45.400 align:start position:0% theoretical asymmetry ratio is 00:13:45.400 --> 00:13:48.450 align:start position:0% theoretical asymmetry ratio is approximately<00:13:46.140> 1,000<00:13:47.140> what<00:13:47.680> I<00:13:47.710> measure<00:13:48.040> is 00:13:48.450 --> 00:13:48.460 align:start position:0% approximately 1,000 what I measure is 00:13:48.460 --> 00:13:52.860 align:start position:0% approximately 1,000 what I measure is approximately<00:13:50.160> 7077<00:13:51.160> so<00:13:51.880> now<00:13:52.270> think<00:13:52.750> about 00:13:52.860 --> 00:13:52.870 align:start position:0% approximately 7077 so now think about 00:13:52.870 --> 00:13:55.080 align:start position:0% approximately 7077 so now think about the<00:13:53.170> Bitcoin<00:13:53.530> blockchain<00:13:53.800> okay<00:13:54.550> so<00:13:54.610> we<00:13:54.940> get 00:13:55.080 --> 00:13:55.090 align:start position:0% the Bitcoin blockchain okay so we get 00:13:55.090 --> 00:13:57.150 align:start position:0% the Bitcoin blockchain okay so we get one<00:13:55.450> megabyte<00:13:55.630> block<00:13:55.870> every<00:13:56.500> 10<00:13:56.680> minutes<00:13:56.860> and 00:13:57.150 --> 00:13:57.160 align:start position:0% one megabyte block every 10 minutes and 00:13:57.160 --> 00:14:00.780 align:start position:0% one megabyte block every 10 minutes and it<00:13:57.790> takes<00:13:58.000> only<00:13:58.210> 11<00:13:59.020> seconds<00:13:59.410> to<00:13:59.560> encode<00:13:59.830> it<00:14:00.010> so 00:14:00.780 --> 00:14:00.790 align:start position:0% it takes only 11 seconds to encode it so 00:14:00.790 --> 00:14:03.300 align:start position:0% it takes only 11 seconds to encode it so it<00:14:01.240> works<00:14:01.540> perfectly<00:14:01.810> for<00:14:02.260> Bitcoin<00:14:02.620> and<00:14:02.860> it 00:14:03.300 --> 00:14:03.310 align:start position:0% it works perfectly for Bitcoin and it 00:14:03.310 --> 00:14:05.550 align:start position:0% it works perfectly for Bitcoin and it was<00:14:03.580> also<00:14:03.880> perfectly<00:14:04.330> for<00:14:04.600> our<00:14:04.750> SK<00:14:05.080> and<00:14:05.290> if<00:14:05.440> I 00:14:05.550 --> 00:14:05.560 align:start position:0% was also perfectly for our SK and if I 00:14:05.560 --> 00:14:07.920 align:start position:0% was also perfectly for our SK and if I receive<00:14:05.770> you<00:14:05.950> and<00:14:06.160> the<00:14:07.030> coding<00:14:07.390> is<00:14:07.480> really 00:14:07.920 --> 00:14:07.930 align:start position:0% receive you and the coding is really 00:14:07.930 --> 00:14:10.590 align:start position:0% receive you and the coding is really fast<00:14:08.170> you<00:14:08.590> get<00:14:08.710> third<00:14:09.190> 71<00:14:10.090> megabytes<00:14:10.510> per 00:14:10.590 --> 00:14:10.600 align:start position:0% fast you get third 71 megabytes per 00:14:10.600 --> 00:14:12.600 align:start position:0% fast you get third 71 megabytes per second<00:14:11.020> so<00:14:11.170> that<00:14:11.200> is<00:14:11.650> not<00:14:11.890> going<00:14:12.220> to<00:14:12.340> interfere 00:14:12.600 --> 00:14:12.610 align:start position:0% second so that is not going to interfere 00:14:12.610 --> 00:14:16.560 align:start position:0% second so that is not going to interfere with<00:14:12.850> your<00:14:13.410> node<00:14:14.410> operations<00:14:15.010> if<00:14:16.000> you<00:14:16.240> want<00:14:16.450> to 00:14:16.560 --> 00:14:16.570 align:start position:0% with your node operations if you want to 00:14:16.570 --> 00:14:18.720 align:start position:0% with your node operations if you want to get<00:14:16.750> a<00:14:16.900> higher<00:14:17.200> symmetry<00:14:17.560> ratio<00:14:18.100> you<00:14:18.310> can<00:14:18.340> take 00:14:18.720 --> 00:14:18.730 align:start position:0% get a higher symmetry ratio you can take 00:14:18.730 --> 00:14:24.810 align:start position:0% get a higher symmetry ratio you can take an<00:14:18.880> equal<00:14:19.830> twenty<00:14:20.830> K<00:14:22.140> and<00:14:23.140> you<00:14:23.170> see<00:14:23.650> RB<00:14:24.040> in<00:14:24.640> the 00:14:24.810 --> 00:14:24.820 align:start position:0% an equal twenty K and you see RB in the 00:14:24.820 --> 00:14:26.490 align:start position:0% an equal twenty K and you see RB in the bones<00:14:25.030> that<00:14:25.510> you<00:14:25.660> can<00:14:25.780> still<00:14:26.050> use<00:14:26.260> for 00:14:26.490 --> 00:14:26.500 align:start position:0% bones that you can still use for 00:14:26.500 --> 00:14:30.450 align:start position:0% bones that you can still use for encoding<00:14:26.920> your<00:14:27.520> blockchain<00:14:28.410> so<00:14:29.410> this<00:14:30.100> this<00:14:30.400> is 00:14:30.450 --> 00:14:30.460 align:start position:0% encoding your blockchain so this this is 00:14:30.460 --> 00:14:35.640 align:start position:0% encoding your blockchain so this this is the<00:14:30.700> one<00:14:31.150> time<00:14:31.390> duction<00:14:31.870> encoding<00:14:33.330> step<00:14:34.650> you 00:14:35.640 --> 00:14:35.650 align:start position:0% the one time duction encoding step you 00:14:35.650 --> 00:14:38.910 align:start position:0% the one time duction encoding step you take<00:14:36.160> your<00:14:37.030> blockchain<00:14:37.810> or<00:14:38.020> your<00:14:38.230> file<00:14:38.560> and 00:14:38.910 --> 00:14:38.920 align:start position:0% take your blockchain or your file and 00:14:38.920 --> 00:14:42.210 align:start position:0% take your blockchain or your file and you<00:14:39.280> split<00:14:39.490> it<00:14:39.700> in<00:14:39.910> and<00:14:40.330> beat<00:14:40.660> chunks<00:14:41.530> and<00:14:41.710> then 00:14:42.210 --> 00:14:42.220 align:start position:0% you split it in and beat chunks and then 00:14:42.220 --> 00:14:44.130 align:start position:0% you split it in and beat chunks and then you<00:14:42.340> scramble<00:14:42.820> each<00:14:42.880> one<00:14:43.150> with<00:14:43.780> your<00:14:43.960> node 00:14:44.130 --> 00:14:44.140 align:start position:0% you scramble each one with your node 00:14:44.140 --> 00:14:46.140 align:start position:0% you scramble each one with your node address<00:14:44.290> and<00:14:44.680> this<00:14:44.980> scrambling<00:14:45.580> is<00:14:45.730> can<00:14:46.030> be 00:14:46.140 --> 00:14:46.150 align:start position:0% address and this scrambling is can be 00:14:46.150 --> 00:14:48.300 align:start position:0% address and this scrambling is can be very<00:14:46.180> simple<00:14:46.630> can<00:14:46.840> be<00:14:46.960> just<00:14:47.170> soaring<00:14:48.070> with<00:14:48.250> a 00:14:48.300 --> 00:14:48.310 align:start position:0% very simple can be just soaring with a 00:14:48.310 --> 00:14:50.640 align:start position:0% very simple can be just soaring with a full<00:14:49.180> domain<00:14:49.360> hash<00:14:49.660> of<00:14:49.900> the<00:14:50.050> of<00:14:50.380> the<00:14:50.500> node 00:14:50.640 --> 00:14:50.650 align:start position:0% full domain hash of the of the node 00:14:50.650 --> 00:14:53.010 align:start position:0% full domain hash of the of the node address<00:14:50.800> and<00:14:51.160> then<00:14:51.640> you<00:14:51.760> encode<00:14:52.390> it<00:14:52.600> with<00:14:52.630> your 00:14:53.010 --> 00:14:53.020 align:start position:0% address and then you encode it with your 00:14:53.020 --> 00:14:56.340 align:start position:0% address and then you encode it with your slow<00:14:53.320> function<00:14:54.060> so<00:14:55.060> this<00:14:55.450> is<00:14:55.600> what<00:14:55.840> a<00:14:56.080> typical 00:14:56.340 --> 00:14:56.350 align:start position:0% slow function so this is what a typical 00:14:56.350 --> 00:14:58.740 align:start position:0% slow function so this is what a typical proof<00:14:56.770> of<00:14:56.950> storage<00:14:57.820> looks<00:14:58.120> like<00:14:58.330> you<00:14:58.600> have 00:14:58.740 --> 00:14:58.750 align:start position:0% proof of storage looks like you have 00:14:58.750 --> 00:15:00.720 align:start position:0% proof of storage looks like you have some<00:14:59.110> kind<00:14:59.350> of<00:14:59.440> memory<00:14:59.710> bone<00:15:00.040> problem<00:15:00.520> because 00:15:00.720 --> 00:15:00.730 align:start position:0% some kind of memory bone problem because 00:15:00.730 --> 00:15:02.430 align:start position:0% some kind of memory bone problem because you<00:15:00.820> want<00:15:01.000> to<00:15:01.090> prove<00:15:01.210> you<00:15:01.360> have<00:15:01.390> a<00:15:01.540> lot<00:15:01.720> of<00:15:01.750> lot 00:15:02.430 --> 00:15:02.440 align:start position:0% you want to prove you have a lot of lot 00:15:02.440 --> 00:15:05.430 align:start position:0% you want to prove you have a lot of lot of<00:15:02.500> data<00:15:02.710> and<00:15:03.040> you<00:15:03.420> transform<00:15:04.420> it<00:15:04.540> into<00:15:04.930> a<00:15:05.140> disk 00:15:05.430 --> 00:15:05.440 align:start position:0% of data and you transform it into a disk 00:15:05.440 --> 00:15:08.520 align:start position:0% of data and you transform it into a disk i/o<00:15:05.680> problem<00:15:06.420> like<00:15:07.420> this<00:15:07.600> you<00:15:07.960> take<00:15:08.140> a<00:15:08.200> seed 00:15:08.520 --> 00:15:08.530 align:start position:0% i/o problem like this you take a seed 00:15:08.530 --> 00:15:10.680 align:start position:0% i/o problem like this you take a seed the<00:15:08.980> verifier<00:15:09.400> will<00:15:09.760> will<00:15:10.060> send<00:15:10.300> you<00:15:10.390> a<00:15:10.420> seed 00:15:10.680 --> 00:15:10.690 align:start position:0% the verifier will will send you a seed 00:15:10.690 --> 00:15:14.040 align:start position:0% the verifier will will send you a seed and<00:15:10.980> from<00:15:11.980> that<00:15:12.160> seed<00:15:12.400> you<00:15:12.700> derive<00:15:13.030> a<00:15:13.270> number 00:15:14.040 --> 00:15:14.050 align:start position:0% and from that seed you derive a number 00:15:14.050 --> 00:15:16.530 align:start position:0% and from that seed you derive a number of<00:15:14.290> positions<00:15:14.680> in<00:15:15.130> the<00:15:15.430> file<00:15:15.640> and<00:15:15.940> then<00:15:16.420> you 00:15:16.530 --> 00:15:16.540 align:start position:0% of positions in the file and then you 00:15:16.540 --> 00:15:18.930 align:start position:0% of positions in the file and then you will<00:15:16.690> just<00:15:16.720> access<00:15:17.530> those<00:15:17.710> positions<00:15:18.040> and<00:15:18.460> and 00:15:18.930 --> 00:15:18.940 align:start position:0% will just access those positions and and 00:15:18.940 --> 00:15:22.290 align:start position:0% will just access those positions and and build<00:15:19.450> a<00:15:19.660> hash<00:15:19.870> okay<00:15:20.800> well<00:15:21.520> the<00:15:21.790> problem<00:15:22.000> with 00:15:22.290 --> 00:15:22.300 align:start position:0% build a hash okay well the problem with 00:15:22.300 --> 00:15:24.150 align:start position:0% build a hash okay well the problem with all<00:15:22.570> these<00:15:22.780> constructions<00:15:23.410> is<00:15:23.590> that<00:15:23.980> they 00:15:24.150 --> 00:15:24.160 align:start position:0% all these constructions is that they 00:15:24.160 --> 00:15:26.520 align:start position:0% all these constructions is that they depend<00:15:24.520> on<00:15:24.760> this<00:15:24.970> technology<00:15:25.570> so<00:15:25.930> if<00:15:26.140> I<00:15:26.290> use 00:15:26.520 --> 00:15:26.530 align:start position:0% depend on this technology so if I use 00:15:26.530 --> 00:15:29.340 align:start position:0% depend on this technology so if I use SSD<00:15:27.160> then<00:15:27.820> the<00:15:28.390> parameters<00:15:28.840> are<00:15:28.930> completely 00:15:29.340 --> 00:15:29.350 align:start position:0% SSD then the parameters are completely 00:15:29.350 --> 00:15:31.800 align:start position:0% SSD then the parameters are completely different<00:15:29.740> if<00:15:29.860> I<00:15:29.980> use<00:15:30.220> a<00:15:30.460> hardest<00:15:31.000> and<00:15:31.210> also 00:15:31.800 --> 00:15:31.810 align:start position:0% different if I use a hardest and also 00:15:31.810 --> 00:15:34.560 align:start position:0% different if I use a hardest and also these<00:15:32.470> disk<00:15:33.040> characteristics<00:15:33.970> properties 00:15:34.560 --> 00:15:34.570 align:start position:0% these disk characteristics properties 00:15:34.570 --> 00:15:37.410 align:start position:0% these disk characteristics properties change<00:15:34.870> all<00:15:35.110> over 00:15:37.410 --> 00:15:37.420 align:start position:0% change all over 00:15:37.420 --> 00:15:41.230 align:start position:0% change all over so<00:15:38.420> this<00:15:38.870> is<00:15:38.990> what<00:15:39.139> we<00:15:39.380> really<00:15:39.649> do<00:15:39.800> we<00:15:40.430> first<00:15:40.730> do 00:15:41.230 --> 00:15:41.240 align:start position:0% so this is what we really do we first do 00:15:41.240 --> 00:15:43.509 align:start position:0% so this is what we really do we first do the<00:15:41.269> step<00:15:41.660> of<00:15:41.899> encoding<00:15:42.740> and<00:15:42.860> creating<00:15:43.399> this 00:15:43.509 --> 00:15:43.519 align:start position:0% the step of encoding and creating this 00:15:43.519 --> 00:15:46.840 align:start position:0% the step of encoding and creating this asymmetry<00:15:43.850> and<00:15:44.800> then<00:15:45.800> we<00:15:46.160> received<00:15:46.550> from<00:15:46.670> the 00:15:46.840 --> 00:15:46.850 align:start position:0% asymmetry and then we received from the 00:15:46.850 --> 00:15:48.819 align:start position:0% asymmetry and then we received from the verifier<00:15:47.269> in<00:15:47.660> this<00:15:47.870> case<00:15:48.110> is<00:15:48.319> the<00:15:48.560> poops 00:15:48.819 --> 00:15:48.829 align:start position:0% verifier in this case is the poops 00:15:48.829 --> 00:15:51.280 align:start position:0% verifier in this case is the poops contract<00:15:49.339> the<00:15:49.970> proof<00:15:50.180> of<00:15:50.329> unique<00:15:50.569> blockchain 00:15:51.280 --> 00:15:51.290 align:start position:0% contract the proof of unique blockchain 00:15:51.290 --> 00:15:53.980 align:start position:0% contract the proof of unique blockchain storage<00:15:51.560> contract<00:15:52.009> we<00:15:52.160> receive<00:15:52.430> a<00:15:52.550> z0<00:15:53.029> with 00:15:53.980 --> 00:15:53.990 align:start position:0% storage contract we receive a z0 with 00:15:53.990 --> 00:15:57.280 align:start position:0% storage contract we receive a z0 with this<00:15:54.199> is<00:15:54.440> zero<00:15:54.740> we<00:15:55.490> will<00:15:55.639> take<00:15:56.389> some<00:15:56.660> parts<00:15:57.050> we 00:15:57.280 --> 00:15:57.290 align:start position:0% this is zero we will take some parts we 00:15:57.290 --> 00:15:59.470 align:start position:0% this is zero we will take some parts we will<00:15:57.410> derive<00:15:57.740> some<00:15:58.190> indexes<00:15:58.790> some<00:15:59.060> parts<00:15:59.420> of 00:15:59.470 --> 00:15:59.480 align:start position:0% will derive some indexes some parts of 00:15:59.480 --> 00:16:01.720 align:start position:0% will derive some indexes some parts of the<00:15:59.630> blockchain<00:15:59.839> or<00:16:00.290> at<00:16:00.649> the<00:16:00.740> file<00:16:00.980> and<00:16:01.190> we 00:16:01.720 --> 00:16:01.730 align:start position:0% the blockchain or at the file and we 00:16:01.730 --> 00:16:04.840 align:start position:0% the blockchain or at the file and we will<00:16:02.000> bring<00:16:02.449> all<00:16:02.690> these<00:16:03.319> into<00:16:03.680> RAM<00:16:03.889> ok<00:16:04.459> so<00:16:04.519> we 00:16:04.840 --> 00:16:04.850 align:start position:0% will bring all these into RAM ok so we 00:16:04.850 --> 00:16:07.749 align:start position:0% will bring all these into RAM ok so we are<00:16:04.930> independent<00:16:05.930> of<00:16:06.050> the<00:16:06.680> technology<00:16:07.250> the 00:16:07.749 --> 00:16:07.759 align:start position:0% are independent of the technology the 00:16:07.759 --> 00:16:10.329 align:start position:0% are independent of the technology the disk<00:16:08.060> access<00:16:08.899> technology<00:16:09.410> and<00:16:09.920> this<00:16:10.100> is<00:16:10.220> the 00:16:10.329 --> 00:16:10.339 align:start position:0% disk access technology and this is the 00:16:10.339 --> 00:16:13.420 align:start position:0% disk access technology and this is the challenge<00:16:10.699> response<00:16:10.910> preparation<00:16:11.870> phase<00:16:12.430> now 00:16:13.420 --> 00:16:13.430 align:start position:0% challenge response preparation phase now 00:16:13.430 --> 00:16:16.480 align:start position:0% challenge response preparation phase now we<00:16:14.269> have<00:16:14.389> we<00:16:14.930> received<00:16:15.350> from<00:16:15.769> the<00:16:16.040> smart 00:16:16.480 --> 00:16:16.490 align:start position:0% we have we received from the smart 00:16:16.490 --> 00:16:18.790 align:start position:0% we have we received from the smart contract<00:16:16.670> like<00:16:17.449> 20<00:16:17.930> seconds<00:16:18.290> later<00:16:18.440> and 00:16:18.790 --> 00:16:18.800 align:start position:0% contract like 20 seconds later and 00:16:18.800 --> 00:16:21.790 align:start position:0% contract like 20 seconds later and second<00:16:19.190> seed<00:16:19.399> ok<00:16:20.029> sit<00:16:20.240> one<00:16:20.449> and<00:16:20.720> well<00:16:21.470> from 00:16:21.790 --> 00:16:21.800 align:start position:0% second seed ok sit one and well from 00:16:21.800 --> 00:16:24.280 align:start position:0% second seed ok sit one and well from seed<00:16:22.009> one<00:16:22.220> we<00:16:22.490> will<00:16:22.639> derive<00:16:22.970> these<00:16:23.389> indexes<00:16:24.019> of 00:16:24.280 --> 00:16:24.290 align:start position:0% seed one we will derive these indexes of 00:16:24.290 --> 00:16:27.340 align:start position:0% seed one we will derive these indexes of RAM<00:16:25.009> where<00:16:25.610> we<00:16:25.790> will<00:16:25.940> take<00:16:26.209> these<00:16:26.480> small 00:16:27.340 --> 00:16:27.350 align:start position:0% RAM where we will take these small 00:16:27.350 --> 00:16:30.189 align:start position:0% RAM where we will take these small pieces<00:16:27.680> small<00:16:28.220> blocks<00:16:28.519> and<00:16:28.790> hash<00:16:29.209> them<00:16:29.449> okay 00:16:30.189 --> 00:16:30.199 align:start position:0% pieces small blocks and hash them okay 00:16:30.199 --> 00:16:32.139 align:start position:0% pieces small blocks and hash them okay well<00:16:30.769> we<00:16:31.069> have<00:16:31.250> transformed<00:16:31.730> this<00:16:31.819> memory 00:16:32.139 --> 00:16:32.149 align:start position:0% well we have transformed this memory 00:16:32.149 --> 00:16:34.389 align:start position:0% well we have transformed this memory bound<00:16:32.420> problem<00:16:32.870> into<00:16:33.230> a<00:16:33.259> CP<00:16:33.560> bone<00:16:33.740> problem 00:16:34.389 --> 00:16:34.399 align:start position:0% bound problem into a CP bone problem 00:16:34.399 --> 00:16:36.790 align:start position:0% bound problem into a CP bone problem well<00:16:34.910> there<00:16:35.269> is<00:16:35.389> some<00:16:35.660> important<00:16:36.440> problem 00:16:36.790 --> 00:16:36.800 align:start position:0% well there is some important problem 00:16:36.800 --> 00:16:39.910 align:start position:0% well there is some important problem here<00:16:37.130> that<00:16:37.850> we<00:16:38.750> cannot<00:16:38.990> do<00:16:39.170> this<00:16:39.319> from<00:16:39.620> a<00:16:39.680> smart 00:16:39.910 --> 00:16:39.920 align:start position:0% here that we cannot do this from a smart 00:16:39.920 --> 00:16:42.850 align:start position:0% here that we cannot do this from a smart contract<00:16:40.339> is<00:16:40.579> that<00:16:40.639> the<00:16:41.209> block<00:16:41.420> interval<00:16:41.959> can 00:16:42.850 --> 00:16:42.860 align:start position:0% contract is that the block interval can 00:16:42.860 --> 00:16:45.610 align:start position:0% contract is that the block interval can be<00:16:42.889> about<00:16:43.189> 10<00:16:43.459> seconds<00:16:43.850> 20<00:16:44.060> seconds<00:16:44.600> so<00:16:44.779> the 00:16:45.610 --> 00:16:45.620 align:start position:0% be about 10 seconds 20 seconds so the 00:16:45.620 --> 00:16:48.129 align:start position:0% be about 10 seconds 20 seconds so the number<00:16:45.949> K<00:16:46.220> the<00:16:46.519> number<00:16:46.670> of<00:16:46.910> pieces<00:16:47.180> we<00:16:47.600> have<00:16:47.959> to 00:16:48.129 --> 00:16:48.139 align:start position:0% number K the number of pieces we have to 00:16:48.139 --> 00:16:51.610 align:start position:0% number K the number of pieces we have to hash<00:16:48.490> to<00:16:49.490> prevent<00:16:49.939> an<00:16:50.149> attacker<00:16:50.509> doing<00:16:51.410> these 00:16:51.610 --> 00:16:51.620 align:start position:0% hash to prevent an attacker doing these 00:16:51.620 --> 00:16:55.389 align:start position:0% hash to prevent an attacker doing these encoding<00:16:52.279> on<00:16:52.399> the<00:16:52.459> fly'<00:16:52.939> will<00:16:53.779> be<00:16:53.899> very<00:16:54.470> very 00:16:55.389 --> 00:16:55.399 align:start position:0% encoding on the fly' will be very very 00:16:55.399 --> 00:16:58.329 align:start position:0% encoding on the fly' will be very very high<00:16:55.699> okay<00:16:56.029> like<00:16:56.389> in<00:16:56.600> the<00:16:56.810> order<00:16:56.990> of<00:16:57.050> 20<00:16:57.620> 20 00:16:58.329 --> 00:16:58.339 align:start position:0% high okay like in the order of 20 20 00:16:58.339 --> 00:17:00.759 align:start position:0% high okay like in the order of 20 20 thousands<00:16:58.790> or<00:16:59.000> maybe<00:16:59.209> more<00:16:59.509> so<00:17:00.290> the<00:17:00.529> proof 00:17:00.759 --> 00:17:00.769 align:start position:0% thousands or maybe more so the proof 00:17:00.769 --> 00:17:03.639 align:start position:0% thousands or maybe more so the proof that<00:17:00.829> we<00:17:01.310> get<00:17:01.490> is<00:17:01.699> very<00:17:02.420> large<00:17:02.689> and<00:17:02.959> the<00:17:03.410> smart 00:17:03.639 --> 00:17:03.649 align:start position:0% that we get is very large and the smart 00:17:03.649 --> 00:17:07.029 align:start position:0% that we get is very large and the smart contract<00:17:03.980> won't<00:17:04.159> be<00:17:04.309> able<00:17:04.699> to<00:17:04.939> you<00:17:05.419> know<00:17:06.039> with 00:17:07.029 --> 00:17:07.039 align:start position:0% contract won't be able to you know with 00:17:07.039 --> 00:17:08.949 align:start position:0% contract won't be able to you know with the<00:17:07.130> gas<00:17:07.309> limit<00:17:07.669> to<00:17:07.909> to<00:17:08.120> evaluate<00:17:08.510> if<00:17:08.720> it<00:17:08.870> is 00:17:08.949 --> 00:17:08.959 align:start position:0% the gas limit to to evaluate if it is 00:17:08.959 --> 00:17:11.770 align:start position:0% the gas limit to to evaluate if it is correct<00:17:09.589> or<00:17:10.069> incorrect<00:17:10.189> so<00:17:10.939> we<00:17:11.329> change<00:17:11.659> the 00:17:11.770 --> 00:17:11.780 align:start position:0% correct or incorrect so we change the 00:17:11.780 --> 00:17:14.439 align:start position:0% correct or incorrect so we change the last<00:17:11.959> part<00:17:12.260> and<00:17:12.439> we<00:17:13.069> transform<00:17:13.579> a<00:17:13.819> CPU<00:17:14.240> bone 00:17:14.439 --> 00:17:14.449 align:start position:0% last part and we transform a CPU bone 00:17:14.449 --> 00:17:17.949 align:start position:0% last part and we transform a CPU bone problem<00:17:14.870> into<00:17:15.319> a<00:17:15.350> memory<00:17:15.980> bus<00:17:16.669> IO<00:17:17.000> problem<00:17:17.750> and 00:17:17.949 --> 00:17:17.959 align:start position:0% problem into a memory bus IO problem and 00:17:17.959 --> 00:17:21.909 align:start position:0% problem into a memory bus IO problem and this<00:17:18.650> has<00:17:18.860> been<00:17:19.039> done<00:17:19.189> oh<00:17:20.439> this<00:17:21.439> has<00:17:21.589> been<00:17:21.620> done 00:17:21.909 --> 00:17:21.919 align:start position:0% this has been done oh this has been done 00:17:21.919 --> 00:17:24.309 align:start position:0% this has been done oh this has been done in<00:17:22.030> Parma<00:17:23.030> coin<00:17:23.209> for<00:17:23.539> instance<00:17:23.839> the<00:17:23.929> same<00:17:24.110> the 00:17:24.309 --> 00:17:24.319 align:start position:0% in Parma coin for instance the same the 00:17:24.319 --> 00:17:26.679 align:start position:0% in Parma coin for instance the same the same<00:17:24.470> procedure<00:17:24.860> so<00:17:25.220> instead<00:17:25.789> of<00:17:25.880> taking<00:17:26.120> a 00:17:26.679 --> 00:17:26.689 align:start position:0% same procedure so instead of taking a 00:17:26.689 --> 00:17:30.820 align:start position:0% same procedure so instead of taking a large<00:17:27.199> number<00:17:27.439> of<00:17:28.690> blocks<00:17:29.690> to<00:17:29.840> hash<00:17:30.110> we<00:17:30.650> take 00:17:30.820 --> 00:17:30.830 align:start position:0% large number of blocks to hash we take 00:17:30.830 --> 00:17:34.810 align:start position:0% large number of blocks to hash we take only<00:17:31.039> 40<00:17:31.610> but<00:17:32.210> we<00:17:32.480> request<00:17:32.929> that<00:17:33.549> the<00:17:34.549> hash 00:17:34.810 --> 00:17:34.820 align:start position:0% only 40 but we request that the hash 00:17:34.820 --> 00:17:38.919 align:start position:0% only 40 but we request that the hash that<00:17:35.330> we<00:17:35.480> obtain<00:17:36.250> has<00:17:37.250> proof-of-work<00:17:37.700> okay<00:17:38.600> so 00:17:38.919 --> 00:17:38.929 align:start position:0% that we obtain has proof-of-work okay so 00:17:38.929 --> 00:17:41.320 align:start position:0% that we obtain has proof-of-work okay so we<00:17:39.080> will<00:17:39.230> try<00:17:39.440> many<00:17:39.919> many<00:17:40.039> times<00:17:40.460> like 00:17:41.320 --> 00:17:41.330 align:start position:0% we will try many many times like 00:17:41.330 --> 00:17:44.590 align:start position:0% we will try many many times like deriving<00:17:41.960> new<00:17:42.470> seeds<00:17:42.950> from<00:17:43.700> the<00:17:43.909> seed<00:17:44.090> 1<00:17:44.299> and<00:17:44.540> a 00:17:44.590 --> 00:17:44.600 align:start position:0% deriving new seeds from the seed 1 and a 00:17:44.600 --> 00:17:47.620 align:start position:0% deriving new seeds from the seed 1 and a nonce<00:17:44.809> you<00:17:45.650> know<00:17:45.740> try<00:17:46.309> a<00:17:46.700> lot<00:17:46.940> of<00:17:46.970> times<00:17:47.270> maybe 00:17:47.620 --> 00:17:47.630 align:start position:0% nonce you know try a lot of times maybe 00:17:47.630 --> 00:17:48.730 align:start position:0% nonce you know try a lot of times maybe 20<00:17:48.140> seconds 00:17:48.730 --> 00:17:48.740 align:start position:0% 20 seconds 00:17:48.740 --> 00:17:51.520 align:start position:0% 20 seconds ten<00:17:48.980> seconds<00:17:49.429> until<00:17:49.580> we'll<00:17:50.300> get<00:17:50.540> one<00:17:50.809> that<00:17:51.290> has 00:17:51.520 --> 00:17:51.530 align:start position:0% ten seconds until we'll get one that has 00:17:51.530 --> 00:17:54.970 align:start position:0% ten seconds until we'll get one that has this<00:17:51.679> property<00:17:52.190> of<00:17:52.340> the<00:17:52.460> proof-of-work<00:17:53.980> so 00:17:54.970 --> 00:17:54.980 align:start position:0% this property of the proof-of-work so 00:17:54.980 --> 00:17:57.040 align:start position:0% this property of the proof-of-work so this<00:17:55.429> is<00:17:55.550> how<00:17:55.730> the<00:17:55.790> whole<00:17:56.179> protocol<00:17:56.540> works<00:17:56.750> and 00:17:57.040 --> 00:17:57.050 align:start position:0% this is how the whole protocol works and 00:17:57.050 --> 00:18:00.280 align:start position:0% this is how the whole protocol works and it's<00:17:57.590> very<00:17:58.100> very<00:17:58.250> simple<00:17:58.730> so<00:17:59.360> in<00:17:59.690> the<00:17:59.929> step 00:18:00.280 --> 00:18:00.290 align:start position:0% it's very very simple so in the step 00:18:00.290 --> 00:18:04.060 align:start position:0% it's very very simple so in the step zero<00:18:00.730> we<00:18:01.730> have<00:18:01.970> this<00:18:02.360> one<00:18:02.660> time<00:18:02.900> encoding<00:18:03.320> but 00:18:04.060 --> 00:18:04.070 align:start position:0% zero we have this one time encoding but 00:18:04.070 --> 00:18:06.700 align:start position:0% zero we have this one time encoding but we<00:18:04.340> also<00:18:04.520> have<00:18:04.850> that<00:18:05.660> who<00:18:06.170> knows<00:18:06.380> we'll 00:18:06.700 --> 00:18:06.710 align:start position:0% we also have that who knows we'll 00:18:06.710 --> 00:18:09.010 align:start position:0% we also have that who knows we'll register<00:18:06.950> with<00:18:07.850> these<00:18:08.059> proofs<00:18:08.450> smart 00:18:09.010 --> 00:18:09.020 align:start position:0% register with these proofs smart 00:18:09.020 --> 00:18:11.530 align:start position:0% register with these proofs smart contract<00:18:09.470> and<00:18:09.710> this<00:18:10.670> can<00:18:10.880> be<00:18:11.030> they<00:18:11.240> don't<00:18:11.360> have 00:18:11.530 --> 00:18:11.540 align:start position:0% contract and this can be they don't have 00:18:11.540 --> 00:18:13.299 align:start position:0% contract and this can be they don't have to<00:18:11.660> reveal<00:18:11.780> their<00:18:12.110> IP<00:18:12.260> they<00:18:12.590> just<00:18:12.830> have<00:18:13.070> to 00:18:13.299 --> 00:18:13.309 align:start position:0% to reveal their IP they just have to 00:18:13.309 --> 00:18:14.980 align:start position:0% to reveal their IP they just have to register 00:18:14.980 --> 00:18:14.990 align:start position:0% register 00:18:14.990 --> 00:18:17.580 align:start position:0% register RSK<00:18:15.590> or<00:18:16.040> receive<00:18:16.400> your<00:18:16.550> address<00:18:16.910> to<00:18:17.240> be<00:18:17.330> paid 00:18:17.580 --> 00:18:17.590 align:start position:0% RSK or receive your address to be paid 00:18:17.590 --> 00:18:20.200 align:start position:0% RSK or receive your address to be paid also<00:18:18.590> they<00:18:18.890> will<00:18:19.070> do<00:18:19.250> some<00:18:19.490> pre<00:18:19.700> deposit 00:18:20.200 --> 00:18:20.210 align:start position:0% also they will do some pre deposit 00:18:20.210 --> 00:18:21.490 align:start position:0% also they will do some pre deposit because<00:18:20.540> they<00:18:20.720> are<00:18:20.809> going<00:18:21.080> to<00:18:21.230> be<00:18:21.350> penalized 00:18:21.490 --> 00:18:21.500 align:start position:0% because they are going to be penalized 00:18:21.500 --> 00:18:25.240 align:start position:0% because they are going to be penalized if<00:18:22.040> they<00:18:22.520> present<00:18:22.760> an<00:18:23.210> embolic<00:18:23.480> proof<00:18:23.800> so<00:18:24.800> in 00:18:25.240 --> 00:18:25.250 align:start position:0% if they present an embolic proof so in 00:18:25.250 --> 00:18:27.940 align:start position:0% if they present an embolic proof so in step<00:18:25.700> one<00:18:25.970> the<00:18:26.360> post<00:18:26.960> contract<00:18:27.440> will<00:18:27.620> derive 00:18:27.940 --> 00:18:27.950 align:start position:0% step one the post contract will derive 00:18:27.950 --> 00:18:30.549 align:start position:0% step one the post contract will derive the<00:18:28.220> seed<00:18:28.429> zero<00:18:28.670> from<00:18:28.910> the<00:18:29.030> block<00:18:29.210> cash<00:18:29.420> and<00:18:29.780> we 00:18:30.549 --> 00:18:30.559 align:start position:0% the seed zero from the block cash and we 00:18:30.559 --> 00:18:32.980 align:start position:0% the seed zero from the block cash and we give<00:18:30.830> the<00:18:31.280> nodes<00:18:31.460> enough<00:18:31.820> time<00:18:32.090> to<00:18:32.360> bring<00:18:32.720> all 00:18:32.980 --> 00:18:32.990 align:start position:0% give the nodes enough time to bring all 00:18:32.990 --> 00:18:36.610 align:start position:0% give the nodes enough time to bring all these<00:18:33.200> pieces<00:18:33.530> or<00:18:33.800> a<00:18:34.130> big<00:18:34.670> piece<00:18:34.880> into<00:18:35.510> Ram<00:18:35.750> so 00:18:36.610 --> 00:18:36.620 align:start position:0% these pieces or a big piece into Ram so 00:18:36.620 --> 00:18:39.370 align:start position:0% these pieces or a big piece into Ram so in<00:18:36.890> step<00:18:37.160> three<00:18:37.660> because<00:18:38.660> the<00:18:38.990> proofs 00:18:39.370 --> 00:18:39.380 align:start position:0% in step three because the proofs 00:18:39.380 --> 00:18:41.610 align:start position:0% in step three because the proofs contract<00:18:39.860> will<00:18:40.010> derive<00:18:40.309> as<00:18:40.550> it<00:18:40.730> won<00:18:40.970> and<00:18:41.270> now 00:18:41.610 --> 00:18:41.620 align:start position:0% contract will derive as it won and now 00:18:41.620 --> 00:18:44.890 align:start position:0% contract will derive as it won and now the<00:18:42.620> competition<00:18:42.890> begins<00:18:43.490> that<00:18:44.059> it's<00:18:44.630> not<00:18:44.840> the 00:18:44.890 --> 00:18:44.900 align:start position:0% the competition begins that it's not the 00:18:44.900 --> 00:18:47.100 align:start position:0% the competition begins that it's not the competition<00:18:45.200> is<00:18:45.410> cooperation<00:18:45.800> actually<00:18:46.250> but 00:18:47.100 --> 00:18:47.110 align:start position:0% competition is cooperation actually but 00:18:47.110 --> 00:18:50.410 align:start position:0% competition is cooperation actually but the<00:18:48.110> full<00:18:48.440> nodes<00:18:48.710> will<00:18:49.070> try<00:18:49.550> to<00:18:49.580> get<00:18:50.240> this 00:18:50.410 --> 00:18:50.420 align:start position:0% the full nodes will try to get this 00:18:50.420 --> 00:18:52.600 align:start position:0% the full nodes will try to get this proof<00:18:50.690> of<00:18:50.809> work<00:18:50.990> will<00:18:51.260> try<00:18:51.559> to<00:18:51.590> get<00:18:52.100> from<00:18:52.340> all 00:18:52.600 --> 00:18:52.610 align:start position:0% proof of work will try to get from all 00:18:52.610 --> 00:18:55.810 align:start position:0% proof of work will try to get from all proof<00:18:53.090> candidates<00:18:53.630> we<00:18:54.170> try<00:18:54.440> to<00:18:54.500> find<00:18:55.160> one<00:18:55.460> that 00:18:55.810 --> 00:18:55.820 align:start position:0% proof candidates we try to find one that 00:18:55.820 --> 00:18:58.810 align:start position:0% proof candidates we try to find one that matches<00:18:56.210> that<00:18:56.450> has<00:18:57.020> a<00:18:57.050> time<00:18:57.350> much<00:18:57.650> that<00:18:58.429> whose 00:18:58.810 --> 00:18:58.820 align:start position:0% matches that has a time much that whose 00:18:58.820 --> 00:19:00.820 align:start position:0% matches that has a time much that whose cash<00:18:59.120> is<00:18:59.330> lower<00:18:59.630> than<00:19:00.080> the<00:19:00.260> proof<00:19:00.590> of<00:19:00.710> work 00:19:00.820 --> 00:19:00.830 align:start position:0% cash is lower than the proof of work 00:19:00.830 --> 00:19:03.520 align:start position:0% cash is lower than the proof of work target<00:19:01.280> so<00:19:01.880> they<00:19:02.360> will<00:19:02.510> submit<00:19:02.750> these<00:19:03.200> proofs 00:19:03.520 --> 00:19:03.530 align:start position:0% target so they will submit these proofs 00:19:03.530 --> 00:19:06.130 align:start position:0% target so they will submit these proofs to<00:19:04.040> the<00:19:04.190> blockchain<00:19:04.790> in<00:19:05.210> normal<00:19:05.840> transaction 00:19:06.130 --> 00:19:06.140 align:start position:0% to the blockchain in normal transaction 00:19:06.140 --> 00:19:08.710 align:start position:0% to the blockchain in normal transaction there<00:19:07.040> will<00:19:07.250> be<00:19:07.280> plenty<00:19:07.640> of<00:19:07.850> time<00:19:07.940> like<00:19:08.360> six 00:19:08.710 --> 00:19:08.720 align:start position:0% there will be plenty of time like six 00:19:08.720 --> 00:19:12.070 align:start position:0% there will be plenty of time like six six<00:19:09.260> blocks<00:19:10.040> ahead<00:19:10.250> to<00:19:10.640> prevent<00:19:11.080> censorship 00:19:12.070 --> 00:19:12.080 align:start position:0% six blocks ahead to prevent censorship 00:19:12.080 --> 00:19:15.160 align:start position:0% six blocks ahead to prevent censorship so<00:19:12.800> that<00:19:12.980> they<00:19:13.100> can<00:19:13.280> do<00:19:13.429> that<00:19:13.580> and<00:19:13.820> in<00:19:14.510> step<00:19:14.840> six 00:19:15.160 --> 00:19:15.170 align:start position:0% so that they can do that and in step six 00:19:15.170 --> 00:19:17.320 align:start position:0% so that they can do that and in step six that<00:19:15.890> there<00:19:16.190> is<00:19:16.250> a<00:19:16.280> deadline<00:19:16.700> for<00:19:16.760> this<00:19:17.059> and 00:19:17.320 --> 00:19:17.330 align:start position:0% that there is a deadline for this and 00:19:17.330 --> 00:19:19.500 align:start position:0% that there is a deadline for this and then<00:19:17.780> an<00:19:17.929> external<00:19:18.410> challenge<00:19:18.830> phase<00:19:19.130> begins 00:19:19.500 --> 00:19:19.510 align:start position:0% then an external challenge phase begins 00:19:19.510 --> 00:19:24.070 align:start position:0% then an external challenge phase begins in<00:19:20.510> this<00:19:20.780> phase<00:19:21.020> who<00:19:21.950> knows<00:19:22.190> we'll<00:19:22.520> try<00:19:23.480> to<00:19:23.540> see 00:19:24.070 --> 00:19:24.080 align:start position:0% in this phase who knows we'll try to see 00:19:24.080 --> 00:19:26.590 align:start position:0% in this phase who knows we'll try to see if<00:19:24.320> the<00:19:24.500> other<00:19:24.650> nodes<00:19:25.010> are<00:19:25.370> we<00:19:25.910> are<00:19:26.179> cheating 00:19:26.590 --> 00:19:26.600 align:start position:0% if the other nodes are we are cheating 00:19:26.600 --> 00:19:30.040 align:start position:0% if the other nodes are we are cheating so<00:19:27.410> they<00:19:27.679> will<00:19:27.830> pick<00:19:28.340> the<00:19:28.520> nonce<00:19:28.730> and<00:19:29.030> then<00:19:29.750> the 00:19:30.040 --> 00:19:30.050 align:start position:0% so they will pick the nonce and then the 00:19:30.050 --> 00:19:32.740 align:start position:0% so they will pick the nonce and then the hash<00:19:30.230> that<00:19:30.470> has<00:19:30.650> been<00:19:30.800> commit<00:19:31.100> from<00:19:32.000> other<00:19:32.150> who 00:19:32.740 --> 00:19:32.750 align:start position:0% hash that has been commit from other who 00:19:32.750 --> 00:19:35.020 align:start position:0% hash that has been commit from other who knows<00:19:32.990> and<00:19:33.260> we'll<00:19:33.860> reevaluate<00:19:34.280> their<00:19:34.700> that 00:19:35.020 --> 00:19:35.030 align:start position:0% knows and we'll reevaluate their that 00:19:35.030 --> 00:19:38.230 align:start position:0% knows and we'll reevaluate their that those<00:19:35.420> proofs<00:19:35.750> but<00:19:36.740> since<00:19:37.100> there<00:19:37.460> are<00:19:37.550> only<00:19:37.580> 40 00:19:38.230 --> 00:19:38.240 align:start position:0% those proofs but since there are only 40 00:19:38.240 --> 00:19:40.570 align:start position:0% those proofs but since there are only 40 elements<00:19:38.480> then<00:19:39.050> it<00:19:39.559> takes<00:19:39.830> about<00:19:39.980> 100 00:19:40.570 --> 00:19:40.580 align:start position:0% elements then it takes about 100 00:19:40.580 --> 00:19:43.120 align:start position:0% elements then it takes about 100 milliseconds<00:19:41.120> so<00:19:41.300> they<00:19:41.450> can<00:19:41.630> just<00:19:42.200> evaluate 00:19:43.120 --> 00:19:43.130 align:start position:0% milliseconds so they can just evaluate 00:19:43.130 --> 00:19:45.160 align:start position:0% milliseconds so they can just evaluate every<00:19:43.940> every<00:19:44.210> other<00:19:44.360> full<00:19:44.690> nodes<00:19:44.929> with 00:19:45.160 --> 00:19:45.170 align:start position:0% every every other full nodes with 00:19:45.170 --> 00:19:48.280 align:start position:0% every every other full nodes with commitment<00:19:46.100> if<00:19:46.880> one<00:19:47.300> of<00:19:47.450> them<00:19:47.600> finds<00:19:47.960> that<00:19:48.050> ham 00:19:48.280 --> 00:19:48.290 align:start position:0% commitment if one of them finds that ham 00:19:48.290 --> 00:19:51.250 align:start position:0% commitment if one of them finds that ham someone<00:19:48.800> has<00:19:49.010> cheated<00:19:49.309> then<00:19:50.059> it<00:19:50.330> just<00:19:50.510> says<00:19:50.750> a 00:19:51.250 --> 00:19:51.260 align:start position:0% someone has cheated then it just says a 00:19:51.260 --> 00:19:53.380 align:start position:0% someone has cheated then it just says a fraud<00:19:51.890> proof<00:19:52.160> to<00:19:52.340> the<00:19:52.429> blockchain<00:19:52.670> to<00:19:52.970> the<00:19:53.059> pub 00:19:53.380 --> 00:19:53.390 align:start position:0% fraud proof to the blockchain to the pub 00:19:53.390 --> 00:19:55.660 align:start position:0% fraud proof to the blockchain to the pub smart<00:19:53.720> contract<00:19:54.140> which<00:19:54.290> is<00:19:54.320> just<00:19:54.830> the<00:19:55.429> full 00:19:55.660 --> 00:19:55.670 align:start position:0% smart contract which is just the full 00:19:55.670 --> 00:19:58.120 align:start position:0% smart contract which is just the full expansion<00:19:56.059> of<00:19:56.480> these<00:19:56.780> of<00:19:57.050> this<00:19:57.320> proof<00:19:57.530> cushion 00:19:58.120 --> 00:19:58.130 align:start position:0% expansion of these of this proof cushion 00:19:58.130 --> 00:20:01.090 align:start position:0% expansion of these of this proof cushion which<00:19:58.460> will<00:19:58.850> show<00:19:59.270> if<00:19:59.570> the<00:20:00.440> original 00:20:01.090 --> 00:20:01.100 align:start position:0% which will show if the original 00:20:01.100 --> 00:20:02.409 align:start position:0% which will show if the original commitment<00:20:01.460> was<00:20:01.730> correct<00:20:02.059> or 00:20:02.409 --> 00:20:02.419 align:start position:0% commitment was correct or 00:20:02.419 --> 00:20:05.489 align:start position:0% commitment was correct or right<00:20:02.539> so<00:20:02.960> in<00:20:03.289> step<00:20:03.559> 9<00:20:03.830> there<00:20:04.549> is<00:20:04.580> a<00:20:04.700> end 00:20:05.489 --> 00:20:05.499 align:start position:0% right so in step 9 there is a end 00:20:05.499 --> 00:20:07.869 align:start position:0% right so in step 9 there is a end deadline<00:20:06.499> for<00:20:06.679> proof<00:20:06.950> submission<00:20:07.489> for<00:20:07.639> fraud 00:20:07.869 --> 00:20:07.879 align:start position:0% deadline for proof submission for fraud 00:20:07.879 --> 00:20:10.090 align:start position:0% deadline for proof submission for fraud to<00:20:08.029> submission<00:20:08.359> and<00:20:08.629> then<00:20:08.840> there<00:20:09.739> Wars<00:20:09.950> has 00:20:10.090 --> 00:20:10.100 align:start position:0% to submission and then there Wars has 00:20:10.100 --> 00:20:12.279 align:start position:0% to submission and then there Wars has been<00:20:10.279> paid<00:20:10.519> of<00:20:10.820> course<00:20:11.090> they<00:20:11.480> are<00:20:11.600> oh<00:20:11.779> they're 00:20:12.279 --> 00:20:12.289 align:start position:0% been paid of course they are oh they're 00:20:12.289 --> 00:20:14.139 align:start position:0% been paid of course they are oh they're only<00:20:12.499> going<00:20:13.100> to<00:20:13.249> be<00:20:13.340> paid<00:20:13.580> to<00:20:13.759> the<00:20:13.850> nodes<00:20:14.059> that 00:20:14.139 --> 00:20:14.149 align:start position:0% only going to be paid to the nodes that 00:20:14.149 --> 00:20:17.830 align:start position:0% only going to be paid to the nodes that are<00:20:14.299> behaved<00:20:14.720> honestly<00:20:15.320> so<00:20:15.859> because<00:20:16.669> the<00:20:17.570> the 00:20:17.830 --> 00:20:17.840 align:start position:0% are behaved honestly so because the the 00:20:17.840 --> 00:20:20.440 align:start position:0% are behaved honestly so because the the were<00:20:17.960> what<00:20:18.169> is<00:20:18.289> going<00:20:18.529> to<00:20:18.559> be<00:20:18.649> shared<00:20:19.450> knows 00:20:20.440 --> 00:20:20.450 align:start position:0% were what is going to be shared knows 00:20:20.450 --> 00:20:22.720 align:start position:0% were what is going to be shared knows who<00:20:21.080> knows<00:20:21.139> are<00:20:21.470> also<00:20:21.730> incentivizes 00:20:22.720 --> 00:20:22.730 align:start position:0% who knows are also incentivizes 00:20:22.730 --> 00:20:27.820 align:start position:0% who knows are also incentivizes incentivize<00:20:23.570> to<00:20:23.840> detect<00:20:24.350> cheaters<00:20:26.830> now 00:20:27.820 --> 00:20:27.830 align:start position:0% incentivize to detect cheaters now 00:20:27.830 --> 00:20:30.039 align:start position:0% incentivize to detect cheaters now what's<00:20:28.129> the<00:20:28.340> difference<00:20:28.489> I<00:20:29.090> said<00:20:29.659> before<00:20:29.809> that 00:20:30.039 --> 00:20:30.049 align:start position:0% what's the difference I said before that 00:20:30.049 --> 00:20:32.109 align:start position:0% what's the difference I said before that this<00:20:30.679> protocol<00:20:31.070> can<00:20:31.190> be<00:20:31.279> used<00:20:31.519> to<00:20:31.669> prove<00:20:31.820> any 00:20:32.109 --> 00:20:32.119 align:start position:0% this protocol can be used to prove any 00:20:32.119 --> 00:20:33.849 align:start position:0% this protocol can be used to prove any file<00:20:32.509> not<00:20:32.779> just<00:20:32.989> the<00:20:33.080> blockchain<00:20:33.289> the 00:20:33.849 --> 00:20:33.859 align:start position:0% file not just the blockchain the 00:20:33.859 --> 00:20:35.259 align:start position:0% file not just the blockchain the blockchain<00:20:34.100> is<00:20:34.220> the<00:20:34.460> easiest<00:20:34.700> one<00:20:34.909> because 00:20:35.259 --> 00:20:35.269 align:start position:0% blockchain is the easiest one because 00:20:35.269 --> 00:20:37.090 align:start position:0% blockchain is the easiest one because the<00:20:35.779> node<00:20:35.960> already<00:20:36.409> has<00:20:36.559> a<00:20:36.590> copy<00:20:36.859> of<00:20:37.009> the 00:20:37.090 --> 00:20:37.100 align:start position:0% the node already has a copy of the 00:20:37.100 --> 00:20:39.330 align:start position:0% the node already has a copy of the blockchain<00:20:37.309> maybe<00:20:37.700> so<00:20:38.090> it<00:20:38.239> can<00:20:38.450> more<00:20:38.720> easily 00:20:39.330 --> 00:20:39.340 align:start position:0% blockchain maybe so it can more easily 00:20:39.340 --> 00:20:42.129 align:start position:0% blockchain maybe so it can more easily evaluate<00:20:40.340> things<00:20:40.580> but<00:20:40.820> it<00:20:40.999> can<00:20:41.059> be<00:20:41.299> used<00:20:41.419> to 00:20:42.129 --> 00:20:42.139 align:start position:0% evaluate things but it can be used to 00:20:42.139 --> 00:20:44.019 align:start position:0% evaluate things but it can be used to any<00:20:42.320> file<00:20:42.590> to<00:20:42.830> create<00:20:43.100> you<00:20:43.340> know<00:20:43.369> a<00:20:43.609> file 00:20:44.019 --> 00:20:44.029 align:start position:0% any file to create you know a file 00:20:44.029 --> 00:20:45.789 align:start position:0% any file to create you know a file sharing<00:20:44.299> system<00:20:44.720> that<00:20:44.899> you<00:20:45.049> can<00:20:45.139> reward<00:20:45.350> node 00:20:45.789 --> 00:20:45.799 align:start position:0% sharing system that you can reward node 00:20:45.799 --> 00:20:48.759 align:start position:0% sharing system that you can reward node just<00:20:46.369> to<00:20:46.580> hold<00:20:46.759> the<00:20:46.970> data<00:20:47.149> for<00:20:47.450> you<00:20:47.769> and 00:20:48.759 --> 00:20:48.769 align:start position:0% just to hold the data for you and 00:20:48.769 --> 00:20:50.349 align:start position:0% just to hold the data for you and multiple<00:20:49.220> copies<00:20:49.399> you<00:20:49.639> can<00:20:49.789> just<00:20:49.999> create<00:20:50.299> a 00:20:50.349 --> 00:20:50.359 align:start position:0% multiple copies you can just create a 00:20:50.359 --> 00:20:53.889 align:start position:0% multiple copies you can just create a contract<00:20:50.779> that<00:20:51.279> create<00:20:52.359> hundred<00:20:53.359> copies<00:20:53.570> of 00:20:53.889 --> 00:20:53.899 align:start position:0% contract that create hundred copies of 00:20:53.899 --> 00:20:56.139 align:start position:0% contract that create hundred copies of the<00:20:54.019> same<00:20:54.139> information<00:20:54.619> but<00:20:55.519> there<00:20:55.879> are<00:20:55.970> some 00:20:56.139 --> 00:20:56.149 align:start position:0% the same information but there are some 00:20:56.149 --> 00:20:57.669 align:start position:0% the same information but there are some difference<00:20:56.570> between<00:20:56.929> the<00:20:57.169> file<00:20:57.379> college 00:20:57.669 --> 00:20:57.679 align:start position:0% difference between the file college 00:20:57.679 --> 00:20:59.560 align:start position:0% difference between the file college group<00:20:57.919> of<00:20:58.039> replication<00:20:58.639> and<00:20:58.789> proof<00:20:59.210> of<00:20:59.330> unique 00:20:59.560 --> 00:20:59.570 align:start position:0% group of replication and proof of unique 00:20:59.570 --> 00:21:01.629 align:start position:0% group of replication and proof of unique file<00:20:59.720> storage<00:20:59.960> proof<00:21:00.679> of<00:21:00.830> replication 00:21:01.629 --> 00:21:01.639 align:start position:0% file storage proof of replication 00:21:01.639 --> 00:21:04.479 align:start position:0% file storage proof of replication depends<00:21:02.359> on<00:21:02.509> the<00:21:02.989> success<00:21:03.259> time<00:21:03.649> so<00:21:03.980> it's 00:21:04.479 --> 00:21:04.489 align:start position:0% depends on the success time so it's 00:21:04.489 --> 00:21:06.190 align:start position:0% depends on the success time so it's difficult<00:21:04.759> to<00:21:04.999> tune<00:21:05.239> for<00:21:05.269> all<00:21:05.629> kinds<00:21:05.960> of<00:21:06.019> discs 00:21:06.190 --> 00:21:06.200 align:start position:0% difficult to tune for all kinds of discs 00:21:06.200 --> 00:21:09.430 align:start position:0% difficult to tune for all kinds of discs and<00:21:06.470> it<00:21:07.039> gives<00:21:07.340> you<00:21:07.639> typical<00:21:08.629> symmetries<00:21:09.409> of 00:21:09.430 --> 00:21:09.440 align:start position:0% and it gives you typical symmetries of 00:21:09.440 --> 00:21:12.549 align:start position:0% and it gives you typical symmetries of about<00:21:09.830> ten<00:21:10.159> to<00:21:10.429> a<00:21:10.460> hundred<00:21:10.549> so<00:21:11.090> it's<00:21:11.809> very<00:21:12.289> easy 00:21:12.549 --> 00:21:12.559 align:start position:0% about ten to a hundred so it's very easy 00:21:12.559 --> 00:21:14.440 align:start position:0% about ten to a hundred so it's very easy that<00:21:12.830> technology<00:21:13.460> changes<00:21:13.489> and<00:21:14.119> then<00:21:14.269> an 00:21:14.440 --> 00:21:14.450 align:start position:0% that technology changes and then an 00:21:14.450 --> 00:21:17.769 align:start position:0% that technology changes and then an attacker<00:21:14.960> is<00:21:15.169> able<00:21:15.379> to<00:21:15.559> to<00:21:16.340> to<00:21:17.119> fake<00:21:17.299> proof<00:21:17.539> on 00:21:17.769 --> 00:21:17.779 align:start position:0% attacker is able to to to fake proof on 00:21:17.779 --> 00:21:19.960 align:start position:0% attacker is able to to to fake proof on the<00:21:18.320> contrary<00:21:18.739> proof<00:21:19.249> of<00:21:19.369> unique<00:21:19.669> file 00:21:19.960 --> 00:21:19.970 align:start position:0% the contrary proof of unique file 00:21:19.970 --> 00:21:22.389 align:start position:0% the contrary proof of unique file storage<00:21:20.299> does<00:21:21.169> not<00:21:21.470> depend<00:21:21.769> on<00:21:21.830> access<00:21:22.190> time 00:21:22.389 --> 00:21:22.399 align:start position:0% storage does not depend on access time 00:21:22.399 --> 00:21:26.139 align:start position:0% storage does not depend on access time and<00:21:22.700> has<00:21:23.629> typical<00:21:24.080> symmetries<00:21:24.619> between<00:21:25.190> 1000 00:21:26.139 --> 00:21:26.149 align:start position:0% and has typical symmetries between 1000 00:21:26.149 --> 00:21:29.619 align:start position:0% and has typical symmetries between 1000 and<00:21:26.769> 10,000<00:21:27.769> and<00:21:27.950> also<00:21:28.669> you<00:21:28.730> can<00:21:28.970> combine<00:21:29.210> them 00:21:29.619 --> 00:21:29.629 align:start position:0% and 10,000 and also you can combine them 00:21:29.629 --> 00:21:32.249 align:start position:0% and 10,000 and also you can combine them so<00:21:30.049> you<00:21:30.109> get<00:21:30.440> 10<00:21:30.649> times<00:21:30.889> more<00:21:31.070> you<00:21:31.220> can<00:21:31.369> combine 00:21:32.249 --> 00:21:32.259 align:start position:0% so you get 10 times more you can combine 00:21:32.259 --> 00:21:36.849 align:start position:0% so you get 10 times more you can combine 10,000<00:21:33.259> of<00:21:33.889> a<00:21:34.070> symmetry<00:21:34.429> 8<00:21:34.639> your<00:21:34.820> of<00:21:35.059> of<00:21:35.859> proof 00:21:36.849 --> 00:21:36.859 align:start position:0% 10,000 of a symmetry 8 your of of proof 00:21:36.859 --> 00:21:39.940 align:start position:0% 10,000 of a symmetry 8 your of of proof of<00:21:37.039> unique<00:21:37.730> block<00:21:37.999> file<00:21:38.450> storage<00:21:38.749> and<00:21:39.049> combine 00:21:39.940 --> 00:21:39.950 align:start position:0% of unique block file storage and combine 00:21:39.950 --> 00:21:42.669 align:start position:0% of unique block file storage and combine them<00:21:40.129> we'll<00:21:40.279> know<00:21:40.669> 10<00:21:40.999> times<00:21:41.239> more<00:21:41.570> for<00:21:42.200> proof 00:21:42.669 --> 00:21:42.679 align:start position:0% them we'll know 10 times more for proof 00:21:42.679 --> 00:21:44.789 align:start position:0% them we'll know 10 times more for proof of<00:21:42.799> replication 00:21:44.789 --> 00:21:44.799 align:start position:0% of replication 00:21:44.799 --> 00:21:48.849 align:start position:0% of replication well<00:21:45.799> the<00:21:46.279> summary<00:21:46.609> is<00:21:46.909> that<00:21:47.450> well<00:21:47.960> the 00:21:48.849 --> 00:21:48.859 align:start position:0% well the summary is that well the 00:21:48.859 --> 00:21:51.849 align:start position:0% well the summary is that well the central<00:21:49.129> asian<00:21:49.279> the<00:21:49.700> centralization<00:21:50.450> is<00:21:50.859> very 00:21:51.849 --> 00:21:51.859 align:start position:0% central asian the centralization is very 00:21:51.859 --> 00:21:54.239 align:start position:0% central asian the centralization is very very<00:21:52.070> important<00:21:52.519> in<00:21:52.669> these<00:21:52.850> networks<00:21:53.090> and 00:21:54.239 --> 00:21:54.249 align:start position:0% very important in these networks and 00:21:54.249 --> 00:21:57.070 align:start position:0% very important in these networks and increasing<00:21:55.249> or<00:21:55.580> setting<00:21:56.149> of<00:21:56.269> a<00:21:56.480> full<00:21:56.749> reward 00:21:57.070 --> 00:21:57.080 align:start position:0% increasing or setting of a full reward 00:21:57.080 --> 00:22:01.269 align:start position:0% increasing or setting of a full reward for<00:21:57.769> the<00:21:57.889> first<00:21:58.129> time<00:21:58.399> we<00:21:58.999> can<00:22:00.279> incentivize 00:22:01.269 --> 00:22:01.279 align:start position:0% for the first time we can incentivize 00:22:01.279 --> 00:22:03.849 align:start position:0% for the first time we can incentivize the<00:22:01.789> creation<00:22:02.179> of<00:22:02.299> new<00:22:02.539> full<00:22:02.779> nodes<00:22:03.019> and<00:22:03.289> keep 00:22:03.849 --> 00:22:03.859 align:start position:0% the creation of new full nodes and keep 00:22:03.859 --> 00:22:06.279 align:start position:0% the creation of new full nodes and keep the<00:22:04.369> number<00:22:04.669> of<00:22:04.700> who<00:22:04.909> nodes<00:22:05.210> even<00:22:05.899> if<00:22:06.049> we 00:22:06.279 --> 00:22:06.289 align:start position:0% the number of who nodes even if we 00:22:06.289 --> 00:22:08.710 align:start position:0% the number of who nodes even if we request<00:22:06.710> them<00:22:06.919> to<00:22:07.190> store<00:22:07.700> 10<00:22:08.179> times<00:22:08.450> more 00:22:08.710 --> 00:22:08.720 align:start position:0% request them to store 10 times more 00:22:08.720 --> 00:22:11.379 align:start position:0% request them to store 10 times more information<00:22:08.899> and<00:22:09.590> this<00:22:10.489> proof<00:22:10.849> of<00:22:11.119> unique 00:22:11.379 --> 00:22:11.389 align:start position:0% information and this proof of unique 00:22:11.389 --> 00:22:13.450 align:start position:0% information and this proof of unique file<00:22:12.259> storage<00:22:12.590> and<00:22:12.859> proof<00:22:13.070> of<00:22:13.190> unique 00:22:13.450 --> 00:22:13.460 align:start position:0% file storage and proof of unique 00:22:13.460 --> 00:22:15.669 align:start position:0% file storage and proof of unique blockchain<00:22:13.970> storage<00:22:14.299> allows<00:22:15.080> you<00:22:15.320> to<00:22:15.440> prove 00:22:15.669 --> 00:22:15.679 align:start position:0% blockchain storage allows you to prove 00:22:15.679 --> 00:22:16.090 align:start position:0% blockchain storage allows you to prove that<00:22:15.710> you 00:22:16.090 --> 00:22:16.100 align:start position:0% that you 00:22:16.100 --> 00:22:18.430 align:start position:0% that you have<00:22:16.250> this<00:22:16.490> unique<00:22:17.000> copy<00:22:17.299> of<00:22:17.630> the<00:22:17.750> file<00:22:17.990> of<00:22:18.260> the 00:22:18.430 --> 00:22:18.440 align:start position:0% have this unique copy of the file of the 00:22:18.440 --> 00:22:20.590 align:start position:0% have this unique copy of the file of the blockchain<00:22:18.710> and<00:22:19.039> the<00:22:19.850> important<00:22:20.240> thing<00:22:20.419> is 00:22:20.590 --> 00:22:20.600 align:start position:0% blockchain and the important thing is 00:22:20.600 --> 00:22:22.960 align:start position:0% blockchain and the important thing is this<00:22:20.809> can<00:22:21.110> be<00:22:21.140> done<00:22:21.440> right<00:22:22.340> from<00:22:22.400> a<00:22:22.730> smart 00:22:22.960 --> 00:22:22.970 align:start position:0% this can be done right from a smart 00:22:22.970 --> 00:22:25.570 align:start position:0% this can be done right from a smart contract<00:22:23.419> with<00:22:23.840> almost<00:22:24.440> no<00:22:24.830> gas<00:22:25.130> consumption 00:22:25.570 --> 00:22:25.580 align:start position:0% contract with almost no gas consumption 00:22:25.580 --> 00:22:28.299 align:start position:0% contract with almost no gas consumption and<00:22:26.110> also<00:22:27.110> the<00:22:27.200> proofs<00:22:27.410> are<00:22:27.650> very<00:22:27.860> short<00:22:28.130> it's 00:22:28.299 --> 00:22:28.309 align:start position:0% and also the proofs are very short it's 00:22:28.309 --> 00:22:30.640 align:start position:0% and also the proofs are very short it's just<00:22:28.549> a<00:22:28.610> hash<00:22:28.820> and<00:22:29.090> a<00:22:29.390> nonce<00:22:29.600> okay<00:22:30.169> so<00:22:30.230> these 00:22:30.640 --> 00:22:30.650 align:start position:0% just a hash and a nonce okay so these 00:22:30.650 --> 00:22:33.279 align:start position:0% just a hash and a nonce okay so these could<00:22:30.890> be<00:22:30.950> implemented<00:22:31.549> in<00:22:31.940> a<00:22:32.360> fume<00:22:32.750> or<00:22:32.960> in<00:22:33.169> our 00:22:33.279 --> 00:22:33.289 align:start position:0% could be implemented in a fume or in our 00:22:33.289 --> 00:22:35.680 align:start position:0% could be implemented in a fume or in our skate<00:22:33.559> amaro<00:22:33.880> well<00:22:34.880> we're<00:22:35.150> working<00:22:35.450> on 00:22:35.680 --> 00:22:35.690 align:start position:0% skate amaro well we're working on 00:22:35.690 --> 00:22:38.110 align:start position:0% skate amaro well we're working on implementation<00:22:36.049> and<00:22:36.650> so<00:22:37.130> when<00:22:37.490> we<00:22:37.760> open 00:22:38.110 --> 00:22:38.120 align:start position:0% implementation and so when we open 00:22:38.120 --> 00:22:40.510 align:start position:0% implementation and so when we open source<00:22:38.360> you<00:22:38.840> will<00:22:38.990> be<00:22:39.110> able<00:22:39.230> to<00:22:39.500> to<00:22:39.919> play<00:22:40.340> with 00:22:40.510 --> 00:22:40.520 align:start position:0% source you will be able to to play with 00:22:40.520 --> 00:22:43.600 align:start position:0% source you will be able to to play with it<00:22:40.990> well<00:22:41.990> thank<00:22:42.260> you<00:22:42.350> very<00:22:42.380> much<00:22:42.740> the 00:22:43.600 --> 00:22:43.610 align:start position:0% it well thank you very much the 00:22:43.610 --> 00:22:45.420 align:start position:0% it well thank you very much the organizers 00:22:45.420 --> 00:22:45.430 align:start position:0% organizers 00:22:45.430 --> 00:22:49.100 align:start position:0% organizers [Applause] 00:22:49.100 --> 00:22:49.110 align:start position:0% 00:22:49.110 --> 00:22:51.900 align:start position:0% you 00:22:51.900 --> 00:22:51.910 align:start position:0% 00:22:51.910 --> 00:22:59.489 align:start position:0% [Music]