Re:NIST advises services to not require that passwords be ch...
by wahern on Monday May 22, 2017 @05:18PM
(#14397013)
Algorithm agility was once considered best practice and all but mandatory.
20+ years of issues with SSL and SSH, both in the standards and implementations, has taught us that the costs of supporting algorithm agility is much more than the gains. Borderline intolerable, in fact. Moreover, our two-decade track record of cryptanalysis and predictions of future breakthroughs has been very good.
We're much better able to predict the costs+benefits of a particular cryptographic primitive than we are of the protocols and software we build. If a cryptographic primitive is assessed as good enough, it's no longer considered desirable or even reasonable to hedge that assessment and permit substitution of the primitive during the lifetime of the protocol. The resultant complexity is much more likely to be the source of future problems than the primitive.
20+ years of issues with SSL and SSH, both in the standards and implementations, has taught us that the costs of supporting algorithm agility is much more than the gains. Borderline intolerable, in fact. Moreover, our two-decade track record of cryptanalysis and predictions of future breakthroughs has been very good.
We're much better able to predict the costs+benefits of a particular cryptographic primitive than we are of the protocols and software we build. If a cryptographic primitive is assessed as good enough, it's no longer considered desirable or even reasonable to hedge that assessment and permit substitution of the primitive during the lifetime of the protocol. The resultant complexity is much more likely to be the source of future problems than the primitive.