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BitTorrent Inventor Bram Cohen Will Start His Own Cryptocurrency
- Kinnard 10y agoHow is this going to be better than scrypt PoW which is designed to be more decentralized by requiring a lot of memory?
- wmf 10y agoScrypt (the version that cryptocurrencies use) is broken, but if you compare memory-hard PoW such as Cuckoo Cycle against proof of space we can assume that most people have more unused storage space than unused RAM and thus space is a cheaper resource, possibly leading to more decentralization.
- mintplant 10y ago> Scrypt is broken Broken how?
- tromp 10y agoProof of Work demands cheap verification, but Hashcash with scrypt requires as much memory and time for verification as a single solution attempt. So while scrypt itself is not broken, its feasibility in a proof of work system with a serious memory footprint (e.g. exceeding a single DRAM chip) is.
- tgragnato 10y agoHe's developing a more detailed discourse about his idea here (in the last 15 minutes).. https://stealthisshow.com/s02e14/ https://stealthisshow.com/s02e14/ http://content.blubrry.com/stealthisshow/S02_E13_The_Future_Of_BitTorrent_with_Bram_Cohen.mp3?_=1 http://content.blubrry.com/stealthisshow/S02_E13_The_Future_...
- wmf 10y agoPrimary source if anyone's interested: https://cyber.stanford.edu/sites/default/files/bramcohen.pdf https://cyber.stanford.edu/sites/default/files/bramcohen.pdf https://www.youtube.com/watch?v=aYG0NxoG7yw&feature=youtu.be https://www.youtube.com/watch?v=aYG0NxoG7yw&feature=youtu.be Of course, the Internet doesn’t remember that he worked on cryptocurrency almost 20 years ago (with Zooko of ZCash) before he started BitTorrent. Pepperidge Farm remembers.
- kurthr 10y agoYeah, and Mojonation with EGfaBT before that... although not really with POW. https://en.wikipedia.org/wiki/Mnet_(peer-to-peer_network) https://en.wikipedia.org/wiki/Mnet_(peer-to-peer_network)
- ecesena 10y agoDoes anyone have more details on slide 9 "Proof of time: Modular roots"? > In group of order 2^k, square k-1 times to find a square root I don't want to say anything stupid, but I don't know if this is trivially true, for instance in [the multiplicative group of] a field of char 2, square is linear and so it's square root. Edit: to clarify, in a field of char 2 the multiplicative group has order 2^q-1, which can't be 2^k. I'm just giving this as an example of a group where square root is fast.
- gizmo686 10y agoI also fine this confusing. From the video, it sounds like the claim is that sqrt(x) = x^(2^(k-1)), which you verify by checking that x=x^(2^k) [0]. However, since the order of the group is 2^k, it is an elementary result of group theory that x^(2^k)=1 [1] [0] That is, you square the claimed root which should be x^(2^(k-1)). EDIT: watching the video some more for clues, he does mention that he uses a particular kind of group, so the claimed property does not need to hold for any group of order 2^k. However, as I argue above, I still don't see how it is possible for any group of order 2^k. [1] This is a direct result of Lagranges theorem. https://en.wikipedia.org/wiki/Lagrange%27s_theorem_(group_theory)#Applications https://en.wikipedia.org/wiki/Lagrange%27s_theorem_(group_th...
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- cbisnett 10y ago“Sometimes people have this misapprehension that Bitcoin is a democracy. No Bitcoin is not a democracy; it’s called a 51% attack for a reason. That’s not a majority of the vote, that’s not how Bitcoin works.” So I get that he's trying to get at the fact that it's not a large majority, but 51% is a majority.
- astrodust 10y agoTechnically 50.0001% should be sufficient, but that doesn't sell as well in the press. It's odd that it wasn't architected to require a super-majority of 60-66% from the outset. That would make it more resilient.
- mquander 10y agoCan you think of a plausible architecture that would satisfy that constraint? I'm not an expert but it's not obvious to me how to do it.
- astrodust 10y agoYou can define your consensus requirements when designing your system. The default is simply majority rules, though in degenerate cases (e.g. two nodes) you can have conflict. If instead it'd been defined as requiring a two-thirds majority then that's how consensus would be achieved. The system would simply halt until that came about.
- SirensOfTitan 10y agoThe 51% attack works because you can use the majority of CPU hash power to write a longer chain faster than the rest of the network. I don't quite follow what you mean here: longest chain wins is a central tenet of cryptocurrency design, and even if you did something with consensus in the product a majority could still hardfork away from that design. Am I missing something here?
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- gkfasdfasdf 10y agoIt would be interesting to know more about how to make mining dependent on space and not cpu. Seems like you could use cpu to compress and create more space, thus pinning it back to cpu?
- sigil 10y agoThere is such a thing as a Memory Hard Function (MHF). cperciva's scrypt was designed to be one, and was subsequently proven to be maximally memory hard. https://eprint.iacr.org/2016/989.pdf https://eprint.iacr.org/2016/989.pdf Litecoin uses scrypt.
- kpcyrd 10y agoYou can only compress to a certain level. For example, you can't compress a sufficiently random bitstream because there are no patterns. See also information theory. I wrote a game for programmers about 5 years ago that used a toy proof-of-storage system. It gave as many 1GB blobs to players as requested, picked random chunks and stored checksums of those. The player doesn't know which chunks have been picked. Some hours later you could start the challenge that you still have the file and the system challenged you to send the checksum of the chunks it picked. If you could answer this, you obviously still have the file and got points. This allowed the system to force a player to store 1GB of data while the verification only needed some bytes of storage.
- TheAceOfHearts 10y agoForgive my ignorance here, but it seems like everyone and their grandmother has been starting their own cryptocurrency lately... Why is this noteworthy? I'll admit that I'm still largely ignorant as to why so many people consider cryptocurrencies to be such a big deal.
- timbowhite 10y ago> why so many people consider cryptocurrencies to be such a big deal. Sending value anywhere in the world in a very short amount of time without having to trust a middleman.
- freehunter 10y agoBut then you have to trust a middleman to convert it into something that's actually usable. It's like gold, I can send it anywhere with DHL or UPS, but my recipient is going to have to find someone to convert it to local currency before they can actually use it. As a result, not many people send gold back and forth.
- StavrosK 10y agoThat's not why your grocery store doesn't accept gold for a pack of gum, though. If you could have an unforgeable, standard-sized, $0.01 nugget of gold, you wouldn't have to convert it, you'd just pay with that. That's what cryptocurrencies could offer.
- kmicklas 10y agoI suspect that is not the reason people do not send gold back and forth.
- cryowaffle 10y agoYou aren't at the NYT.com, this is an uncurated niche technology site that aggregates a massive amount of bubbling news content.
- chfs 10y ago
- polyomino 10y agoWorth noting, there is already a coin called burstcoin that does what he's proposing.
- deleted 10y ago[deleted]
- ozten 10y agoThis is addressed in the Youtube page's comment section by Bram Cohen "Burstcoin is busted. For proofs of work you can throw any random bullshit together and it will be a functioning proof of work. Proofs of space aren't like that."
- polyomino 10y agoThat quote is unsubstantiated. Burstcoin has been working fine for years.
- small_hammer 10y agoBold claims are dangerous.