On Mon, Feb 22, 2010 at 8:52 AM, Roy Arends <r...@dnss.ec> wrote: > On Feb 22, 2010, at 11:12 AM, Evan Hunt wrote: > >>> Using NSEC instead of NSEC3 because you fear SHA1 collisions does not >>> seem sensible, as if you fear SHA1 collisions, you have other more >>> significant problems with DNSSEC to worry about, and thus this is >>> not, in my opinion, reasonable. And it isn't sensible to suggest >>> users worry about it. If we are going to mention it, it should be >>> in security considerations, saying NSEC3 is dependent upon certain >>> properties of its hash algorithm (I forget now whether it is >>> collision resistance, pre-image resistance or or what), but this >>> should also point out the whole of DNSSEC is predicated on similar >>> qualities. >> >> +1 except for the "if". It is mathematically possible for collisions to >> occur with one approach and not the other, and it would be irresponsible >> not to make note of the fact, even if we agree that the chances of this >> occurring in nature are negligible. > > This is absurd. If we're going to do this, I'd like the security > considerations to reflect all of the non-zero probabilities of errors > occuring (those that have a higher probability). This includes software-bugs, > hardware-bugs, probability of advances in factorization, randomness of PRNG > for DNSKEYs, faulty calibration/low granularity of equipment measuring the > transition between the two hyperfine levels of the ground state of the > caesium 133 atom. Gravitational Sphere of Influence of the 99942 Apophis on > the Gravitational orbit of GPS satelites (Still having a higher probability > than hash-collisions ;-)), Drunk Sysadmins, Rouge Registrar, etc, etc. > > I'm sure that it will be a very large section.
Precisely. I realize it's hard to grasp precisely how small the statistical chances of a collision are, but they are just unbelievably small. Acting as if it is something that might actually happen just makes you look silly. -Ekr _______________________________________________ DNSOP mailing list DNSOP@ietf.org https://www.ietf.org/mailman/listinfo/dnsop
