Re: [Bitcoin-development] Mining centralization pressure from non-uniform propagation speed

2015-06-18 Thread Yifu Guo
Nice insight Peter, This further confirms the real problem, which doesn't have much to do with blocksize but rather the connectivity of nodes in countries with not-so-friendly internet policies and deceptive connectivity. On Thu, Jun 18, 2015 at 6:00 PM, Tom Harding wrote: > On 06/12/2015 06:5

Re: [Bitcoin-development] Mining centralization pressure from non-uniform propagation speed

2015-06-18 Thread Tom Harding
On 06/12/2015 06:51 PM, Pieter Wuille wrote: >> However, it does very clearly show the effects of >> larger blocks on centralization pressure of the system. On 6/14/2015 10:45 AM, Jonas Nick wrote: > This means that your scenario is not the result of a cartel but the result of > a long-term netwo

Re: [Bitcoin-development] Mining centralization pressure from non-uniform propagation speed

2015-06-14 Thread Jonas Nick
Hi all, it's a very useful approach to also model fees and you came up with an interesting scenario. Assuming that you meant that the groups are only connected with a single link, I've recreated the scenario with Gavin's simulation and got similar results. The group with the large hashrate does p

Re: [Bitcoin-development] Mining centralization pressure from non-uniform propagation speed

2015-06-12 Thread Pieter Wuille
If there is a benefit in producing larger more-fee blocks if they propagate slowly, then there is also a benefit in including high-fee transactions that are unlikely to propagate quickly through optimized relay protocols (for example: very recent transactions, or out-of-band receoved ones). This ef

Re: [Bitcoin-development] Mining centralization pressure from non-uniform propagation speed

2015-06-12 Thread Peter Todd
On Fri, Jun 12, 2015 at 01:21:46PM -0400, Gavin Andresen wrote: > Nice work, Pieter. You're right that my simulation assumed bandwidth for > 'block' messages isn't the bottleneck. > > But doesn't Matt's fast relay network (and the work I believe we're both > planning on doing in the near future to

Re: [Bitcoin-development] Mining centralization pressure from non-uniform propagation speed

2015-06-12 Thread Mike Hearn
Sure, and you did indeed say that. -- ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-developme

Re: [Bitcoin-development] Mining centralization pressure from non-uniform propagation speed

2015-06-12 Thread Pieter Wuille
I'm merely proving the existence of the effect. On Jun 12, 2015 8:24 PM, "Mike Hearn" wrote: > are only connected to each other through a slow 2 Mbit/s link. >> > > That's very slow indeed. For comparison, plain old 3G connections > routinely cruise around 7-8 Mbit/sec. > > So this simulation is

Re: [Bitcoin-development] Mining centralization pressure from non-uniform propagation speed

2015-06-12 Thread Mike Hearn
> > are only connected to each other through a slow 2 Mbit/s link. > That's very slow indeed. For comparison, plain old 3G connections routinely cruise around 7-8 Mbit/sec. So this simulation is assuming a speed dramatically worse than a mobile phone can get! -

Re: [Bitcoin-development] Mining centralization pressure from non-uniform propagation speed

2015-06-12 Thread Peter Todd
On Fri, Jun 12, 2015 at 06:51:02PM +0200, Pieter Wuille wrote: > The configuration used in the code right now simulates two groups of miners > (one 80%=25%+25%+30%, one 20%=5%+5%+5%+5%), which are well-connected > internally, but are only connected to each other through a slow 2 Mbit/s > link. > >

Re: [Bitcoin-development] Mining centralization pressure from non-uniform propagation speed

2015-06-12 Thread Gavin Andresen
Nice work, Pieter. You're right that my simulation assumed bandwidth for 'block' messages isn't the bottleneck. But doesn't Matt's fast relay network (and the work I believe we're both planning on doing in the near future to further optimize block propagation) make both of our simulations irreleva

[Bitcoin-development] Mining centralization pressure from non-uniform propagation speed

2015-06-12 Thread Pieter Wuille
Hello all, I've created a simulator for Bitcoin mining which goes a bit further than the one Gavin used for his blog post a while ago. The main difference is support for links with different latency and bandwidth, because of the clustered configuration described below. In addition, it supports dif