<div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On Tue, May 12, 2015 at 7:48 PM, Adam Back <span dir="ltr"><<a href="mailto:adam@cypherspace.org" target="_blank">adam@cypherspace.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">I think its fair to say no one knows how to make a consensus that<br>
works in a decentralised fashion that doesnt weaken the bitcoin<br>
security model without proof-of-work for now.<br></blockquote><div><br></div><div>Yes.</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">I am presuming Gavin is just saying in the context of not pre-judging<br>
the future that maybe in the far future another innovation might be<br>
found (or alternatively maybe its not mathematically possible).<br></blockquote><div><br></div><div>Yes... or an alternative might be found that weakens the Bitcoin security model by a small enough amount that it either doesn't matter or the weakening is vastly overwhelmed by some other benefit.</div><div><br></div><div>I'm influenced by the way the Internet works; packets addressed to 74.125.226.67 reliably get to Google through a very decentralized system that I'll freely admit I don't understand. Yes, a determined attacker can re-route packets, but layers of security on top means re-routing packets isn't enough to pull off profitable attacks.</div><div><br></div><div>I think Bitcoin's proof-of-work might evolve in a similar way. Yes, you might be able to 51% attack the POW, but layers of security on top of POW will mean that won't be enough to pull off profitable attacks.</div></div><div><br></div><div><br></div>-- <br><div class="gmail_signature">--<br>Gavin Andresen<br></div><div class="gmail_signature"><br></div>
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