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Thanks for taking the time to research and respond! So: 1) Dan's comments on Bitcoin in that BI article are a bit subtler than that. The very last section sugg

Thanks for taking the time to research and respond! So: 1) Dan's comments on Bitcoin in that BI article are a bit subtler than that. The very last section suggests (to me) that despite what value the BTC protocol has, it doesn't "square the triangle." 2) Dan is mainly talking about Sybil attacks in his 2011 post. The difference between a 51% attack and a Sybil attack is somewhat blurry, but here's my understanding: A Sybil attack can't be prevented if an attacker controls >33% of the nodes. This is a mathematical truth of distributed systems (cf. Byzantine Generals), but Bitcoin's proof-of-work is often cited as the first practical system to demonstrate a workaround. The >50% problem becomes the new lower bound for attackers, because with proof-of-work, you can't just fake 33% of the nodes. They have to be participating in the number crunching. However, recent research blew this entirely out of the water, at least as far as Bitcoin goes[0]. They propose a change to the protocol that makes it a >25% percent problem, but currently it is a >0% problem. That is kind of a big deal. There are some good ideas in the "proof of stake" discussions, but none of the answers appear to lend support to the "triangle is squared" hypothesis. Now then: I think you misunderstood my remark about the political aspects. I'm not saying anyone agrees on who/what/when/why/how of privacy issues. If the goal is to describe a system that is resilient to eavesdropping, you shouldn't distract from that system in the same paper with so much argument about why you want a system resilient to eavesdropping. Spill your ink to convince people if your system meets the requirements you lay out. Finally: - "meta-domain" is a very strange term to use. It makes you sound ignorant of the realities of DNS, whether you are or not. - My statement was that a proxy to namecoin doesn't add much to the system. The first and fourth of your bullet points might be paraphrased as "but it adds a proxy to namecoin!" - What would be the purpose of adding DNSCrypt to DNSNMC? What do you mean by "secure queries" there? Anonymous queries? Validated responses? It's okay if you haven't finished specifying DNSNMC yet, but I wasn't asking for guesses about what you might do in the future. Meanwhile, don't let counter arguments discourage you, but remember that the problem space is large. Failure to solve a gigantic problem may still be success when solving a normal sized problem. [0] http://arxiv.org/abs/1311.0243 http://arxiv.org/abs/1311.0243

itistoday2 13y ago
Again, excellent comments! :D > The very last section suggests (to me) that despite what value the BTC protocol has, it doesn't "square the triangle." How so? > However, recent research blew this entirely out of the water, at least as far as Bitcoin goes[0]. They propose a change to the protocol that makes it a >25% percent problem, but currently it is a >0% problem. That is kind of a big deal. There are some good ideas in the "proof of stake" discussions, but none of the answers appear to lend support to the "triangle is squared" hypothesis. I was looking for that paper a while ago! Somehow my google-fu failed me and I got distracted by something else, and so, forgot about it for a while. Thanks to you, I've had a chance to download the paper and read it. Indeed, at first glance it might seem like they're pointing out a big hole in BTC, but I don't think this is the case, and neither do a lot of other folks over on the BTCtalk forum. [1] There is one big flaw in their paper that the authors acknowledge (quite poorly IMO) in their followup blog post to the reactions that they received [2], and that is point #9, that they for some reason buried toward the bottom of the blog post: Our paper does not address what happens when multiple pools employ the selfish strategy. But if all pools were selfish, the blockchain would not make forward progress for large periods of time, while selfish groups hoard their blocks. Then, perhaps, depending on the profit- taking strategy of the selfish miners and their relative sizes, it would take erratic large steps forward. Such erratic behavior would not bode well for the users who want to transact in the currency. Indeed, what happens if more than one pool decides to follow this strategy? They must have been too trigger-happy to publish their paper to analyze the significance of that rather obvious question, which demands an answer. I say that it demands an answer because the probability that exactly one pool would implement this strategy is, I think, close to zero. For some strange reason, the authors (in their blog post) decided to jump to the other extreme and analyze the case where "all pools were selfish"! Well, that's a rather silly thing to do, because you don't go from 0% to 100% in one leap like that, so their analysis there, and related commentary, can simply be dismissed. The interesting question remains: what happens when some pools start to implement this strategy? I do not know for sure, but I suspect that the result will be a wash, so to speak, and most likely will end poorly for the cheaters (when they are caught). Their entire paper is based on the absurd claim that a single selfish pool will grow, like some sort of cancer, until it reaches 51% proportions (and then it's game over). While this is a possibility, at the moment it seems like an exceedingly remote one. In fact, the more cheating pools there are that use this strategy, the less likely their vision of a BTC doomsday becomes. Which group of bandits should one join, and is it worth the risk? Speaking of risk, Stephen Gornick quickly pointed out a simple technique for detecting these cheaters: " Wouldn't it be easy to tell if a block seems to be coming from a selfish pool (as each new block will appear to be laggng since it has no recently arrived transactions)? So if this lag can be detected then cannot an incentive to honest pools be offered?" [3] > If the goal is to describe a system that is resilient to eavesdropping, you shouldn't distract from that system in the same paper with so much argument about why you want a system resilient to eavesdropping. On this issue, I think we simply differ in opinion. I did not consider that section to be a distraction. Rather, I considered it to be an essential part of the paper, without which it would have been lacking. I think it would have been a disservice to the two projects (and to the paper itself) had I left the motivation section out. Only a tiny fraction of the intended audience of the paper is like you (already convinced of the need for an ubiquitous surveillance proof system of communication). > "meta-domain" is a very strange term to use. It makes you sound ignorant of the realities of DNS, whether you are or not. What term would you prefer then? It's a somewhat novel concept (so far as I know). > My statement was that a proxy to namecoin doesn't add much to the system. The first and fourth of your bullet points might be paraphrased as "but it adds a proxy to namecoin!" I agree on your last point, that the first and fourth bullets can be (somewhat inaccurately) summarized in that way, but I strongly disagree with the notion that it "doesn't add much to the system." It makes Namecoin usable. That's huge. > What would be the purpose of adding DNSCrypt to DNSNMC? What do you mean by "secure queries" there? Anonymous queries? Validated responses? It's okay if you haven't finished specifying DNSNMC yet, but I wasn't asking for guesses about what you might do in the future. Sorry, by "secure queries" I meant "encrypted queries". It protects against another form of surveillance. Thank you very much for your wonderful, very astute comments! [1] https://bitcointalk.org/index.php?topic=324413.0 https://bitcointalk.org/index.php?topic=324413.0 [2] http://hackingdistributed.com/2013/11/14/response-to-feedback-on-selfish-mining/ http://hackingdistributed.com/2013/11/14/response-to-feedbac... [3] https://bitcointalk.org/index.php?topic=324413.msg3478147#msg3478147 https://bitcointalk.org/index.php?topic=324413.msg3478147#ms...

itistoday2 13y ago

Again, excellent comments! :D > The very last section suggests (to me) that despite what value the BTC protocol has, it doesn't "square the triangle." How so? > However, recent research blew this entirely out of the water, at least as far as Bitcoin goes[0]. They propose a change to the protocol that makes it a >25% percent problem, but currently it is a >0% problem. That is kind of a big deal. There are some good ideas in the "proof of stake" discussions, but none of the answers appear to lend support to the "triangle is squared" hypothesis. I was looking for that paper a while ago! Somehow my google-fu failed me and I got distracted by something else, and so, forgot about it for a while. Thanks to you, I've had a chance to download the paper and read it. Indeed, at first glance it might seem like they're pointing out a big hole in BTC, but I don't think this is the case, and neither do a lot of other folks over on the BTCtalk forum. [1] There is one big flaw in their paper that the authors acknowledge (quite poorly IMO) in their followup blog post to the reactions that they received [2], and that is point #9, that they for some reason buried toward the bottom of the blog post: Our paper does not address what happens when multiple pools employ the selfish strategy. But if all pools were selfish, the blockchain would not make forward progress for large periods of time, while selfish groups hoard their blocks. Then, perhaps, depending on the profit- taking strategy of the selfish miners and their relative sizes, it would take erratic large steps forward. Such erratic behavior would not bode well for the users who want to transact in the currency. Indeed, what happens if more than one pool decides to follow this strategy? They must have been too trigger-happy to publish their paper to analyze the significance of that rather obvious question, which demands an answer. I say that it demands an answer because the probability that exactly one pool would implement this strategy is, I think, close to zero. For some strange reason, the authors (in their blog post) decided to jump to the other extreme and analyze the case where "all pools were selfish"! Well, that's a rather silly thing to do, because you don't go from 0% to 100% in one leap like that, so their analysis there, and related commentary, can simply be dismissed. The interesting question remains: what happens when some pools start to implement this strategy? I do not know for sure, but I suspect that the result will be a wash, so to speak, and most likely will end poorly for the cheaters (when they are caught). Their entire paper is based on the absurd claim that a single selfish pool will grow, like some sort of cancer, until it reaches 51% proportions (and then it's game over). While this is a possibility, at the moment it seems like an exceedingly remote one. In fact, the more cheating pools there are that use this strategy, the less likely their vision of a BTC doomsday becomes. Which group of bandits should one join, and is it worth the risk? Speaking of risk, Stephen Gornick quickly pointed out a simple technique for detecting these cheaters: " Wouldn't it be easy to tell if a block seems to be coming from a selfish pool (as each new block will appear to be laggng since it has no recently arrived transactions)? So if this lag can be detected then cannot an incentive to honest pools be offered?" [3] > If the goal is to describe a system that is resilient to eavesdropping, you shouldn't distract from that system in the same paper with so much argument about why you want a system resilient to eavesdropping. On this issue, I think we simply differ in opinion. I did not consider that section to be a distraction. Rather, I considered it to be an essential part of the paper, without which it would have been lacking. I think it would have been a disservice to the two projects (and to the paper itself) had I left the motivation section out. Only a tiny fraction of the intended audience of the paper is like you (already convinced of the need for an ubiquitous surveillance proof system of communication). > "meta-domain" is a very strange term to use. It makes you sound ignorant of the realities of DNS, whether you are or not. What term would you prefer then? It's a somewhat novel concept (so far as I know). > My statement was that a proxy to namecoin doesn't add much to the system. The first and fourth of your bullet points might be paraphrased as "but it adds a proxy to namecoin!" I agree on your last point, that the first and fourth bullets can be (somewhat inaccurately) summarized in that way, but I strongly disagree with the notion that it "doesn't add much to the system." It makes Namecoin usable. That's huge. > What would be the purpose of adding DNSCrypt to DNSNMC? What do you mean by "secure queries" there? Anonymous queries? Validated responses? It's okay if you haven't finished specifying DNSNMC yet, but I wasn't asking for guesses about what you might do in the future. Sorry, by "secure queries" I meant "encrypted queries". It protects against another form of surveillance. Thank you very much for your wonderful, very astute comments! [1] https://bitcointalk.org/index.php?topic=324413.0 https://bitcointalk.org/index.php?topic=324413.0 [2] http://hackingdistributed.com/2013/11/14/response-to-feedback-on-selfish-mining/ http://hackingdistributed.com/2013/11/14/response-to-feedbac... [3] https://bitcointalk.org/index.php?topic=324413.msg3478147#msg3478147 https://bitcointalk.org/index.php?topic=324413.msg3478147#ms...