-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 02/22/2015 10:17 AM, Natanael wrote: > The problem with this approach is that it is worthless as a > predictor. We aren't dealing with traffic safety and road design - > we are dealing with adaptive attackers and malicious miners and > pools. > > Anything which does not invalidate blocks carrying doublespends > WILL allow malicious miners and pools to conspire with thieves to > steal money. The probability of being hit will then be (their > proliferation in your business area) * (their fraction of the > mining power). > > That might seem to give small numbers for most sets of reasonable > assumptions. But the problem is that's only an average, and the > people being hit might have small profit margins - one successful > attack can place hundreds of merchants in red numbers and force > them to shut down. > > You should never expose yourself to attacks which you can't defend > against and which can be fatal. In particular not if there's > nothing in the environment that is capable of limiting the size or > numbers of any attacks. And there's no such thing today in > Bitcoin. > > This is why I sketched out the multisignature notary approach, and > why some decided to extend that approach with collateral > (NoRiskWallet) to further reduce trust in the notary. This is the > single most practical approach I know of today to achieve ACTUAL > SECURITY for unconfirmed transactions. > > Don't like it? See if you can do better! > > Just don't rely on zero-confirmation transactions! You just disproved your own argument. It is possible to predict risk, and therefore to price the risk. You also noted that for some Bitcoin users, the price of that risk is too high for the types of transactions in which wish to engage. In what way does that translated into a universal requirement for everybody to use multisignature notaries? Surely the users who can afford the risk can use zero conf if they like, and those who can't can use multisig notaries? -----BEGIN PGP SIGNATURE----- iQIcBAEBAgAGBQJU6gLmAAoJECpf2nDq2eYj8/AQAJfMtBqjo1Z2Z0A7OhE9iaYD PqWXdRaCFwyV49RSDrRROrB9Vc7CENQsweHBSnNEmSj6la/YfjyobmaR5BMtTq73 ZaXOFYSGVa9S0j+1qTvz2MorBd6ocxckdunfN7N/uVb4NQRYTHUT8N7AyJgRFYO9 ElQU/8TcNCSRqSQc3z8rnUc8eN1+DgqkMDHM754huOgA0fz0OlxnLCddcCvLr0t7 ZPCtZI94FWQSWhzTK2oa41hh01xG+Eg5GhqGzM7WBqM6+d/CgNcUVeMnVOkkhgav AmlE81Km9R4AlrsGT/CcGgaC+FvBhqmDYHAGOUG3hLP+MXMe4qA5TRoRKHFvq4Gw nF6q+leI7z/TkKeiDcyEKKen5cU01SnZlVRnncccIxsjzNjCiBdXOTP6o0pTd34j 5VJQ04mF4sla5AaaSDtsbkZuMdqIZDMn1tWxbmXRQ2cUbCGoi4yYiUlqjetrs4e1 i7NopccLNVDwjGRRnaSs4KkpuW7s23XwKm6WVehrP7S9s1Bqc+84C/rL1G4IF3Ul vOz+dfxpS+yeGdEDOxb92voKo+fvL/N1sH2+cqTemuYWArDOn1kK/qKdaEfnl9p2 VcPJWuik6Ywomg4fCWmTQWcDxbWiUT/Gb/niONOYQ6iJG7mU4SH9LFBDd8qV+ljN RqUYrOBf/PaMneNxwJp+ =w36r -----END PGP SIGNATURE-----