It's an interval (a,b) where a, b are between 0 and 21*10^6*10^8 . Somebody pointed out that this is not easily accomplished using the current code because there are no coin ids. On Wed, Dec 9, 2015 at 4:16 PM, Loi Luu wrote: > I guess the most basic question is how do you define a coin here? > > Thanks, > Loi Luu > On 10 Dec 2015 2:26 a.m., "Akiva Lichtner" > wrote: > >> Thanks for giving serious consideration to my post. >> >> With regard to your question "if a transaction spends a "coin" that >> ends in "1" and creates a new coin that ends in "1", which partition >> should process the transaction?", I would answer that only one >> partition is involved. In other words, there are N independent block >> chains that never cross paths. >> >> With regard to your question "what is the prior data needed to >> validate that kind of TXs?" I do not understand what this means. If >> you can dumb it down a bit that would be good because there could be >> some interesting concern in this question. >> >> Since partitions are completely segregated, there is no need for a >> node to work on multiple partitions simultaneously. For attacks to be >> defeated a node needs to be able to work on multiple partitions in >> turn, not at the same time. The reason is because if the computing >> power of the good-faith nodes is unbalanced this gives attackers an >> unfair advantage. >> >> On 12/9/15, Loi Luu via bitcoin-dev >> wrote: >> > Dear Akiva, >> > >> > Its Loi Luu, one of the authors of the SCP protocol ( >> > http://eprint.iacr.org/2015/1168.pdf ). >> > >> > Before SCP, we had been thinking hard about how to do sharding >> efficiently >> > without degrading any security guarantee. A simple solution which splits >> > the coins, or TXs in to several partitions will just not work. You have >> to >> > answer more questions to have a good solutions. For example, I wonder in >> > your proposal, if a transaction spends a "coin" that ends in "1" and >> > creates a new coin that ends in "1", which partition should process the >> > transaction? What is the prior data needed to validate that kind of TXs? >> > >> > The problem with other proposals, and probably yours as well, that we >> see >> > is that the amount of data that you need to broadcast immediately to the >> > network increases linearly with the number of TXs that the network can >> > process. Thus, sharding does not bring any advantage than simply using >> > other techniques to publish more blocks in one epoch (like Bitcoin-NG, >> > Ghost). The whole point of using sharding/ partition is to localize >> > the bandwidth used, and only broadcast only a minimal data to the >> network. >> > >> > Clearly we are able to localize the bandwidth used with our SCP >> protocol. >> > The cost is that now recipients need to themselves verify whether a >> > transaction is double spending. However, we think that it is a >> reasonable >> > tradeoff, given the potential scalability that SCP can provides. >> > >> > Thanks, >> > Loi Luu. >> > >> > On Wed, Dec 9, 2015 at 12:27 AM, Akiva Lichtner via bitcoin-dev < >> > bitcoin-dev@lists.linuxfoundation.org> wrote: >> > >> >> Hello, >> >> >> >> I am seeking some expert feedback on an idea for scaling Bitcoin. As a >> >> brief introduction: I work in the payment industry and I have twenty >> >> years' >> >> experience in development. I have some experience with process groups >> and >> >> ordering protocols too. I think I understand Satoshi's paper but I >> admit >> >> I >> >> have not read the source code. >> >> >> >> The idea is to run more than one simultaneous chain, each chain >> defeating >> >> double spending on only part of the coin. The coin would be partitioned >> >> by >> >> radix (or modulus, not sure what to call it.) For example in order to >> >> multiply throughput by a factor of ten you could run ten parallel >> chains, >> >> one would work on coin that ends in "0", one on coin that ends in "1", >> >> and >> >> so on up to "9". >> >> >> >> The number of chains could increase automatically over time based on >> the >> >> moving average of transaction volume. >> >> >> >> Blocks would have to contain the number of the partition they belong >> to, >> >> and miners would have to round-robin through partitions so that an >> >> attacker >> >> would not have an unfair advantage working on just one partition. >> >> >> >> I don't think there is much impact to miners, but clients would have to >> >> send more than one message in order to spend money. Client messages >> will >> >> need to enumerate coin using some sort of compression, to save space. >> >> This >> >> seems okay to me since often in computing client software does have to >> >> break things up in equal parts (e.g. memory pages, file system blocks,) >> >> and >> >> the client software could hide the details. >> >> >> >> Best wishes for continued success to the project. >> >> >> >> Regards, >> >> Akiva >> >> >> >> P.S. I found a funny anagram for SATOSHI NAKAMOTO: "NSA IS OOOK AT >> MATH" >> >> >> >> >> >> _______________________________________________ >> >> bitcoin-dev mailing list >> >> bitcoin-dev@lists.linuxfoundation.org >> >> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev >> >> >> >> >> > >> >