On 9/06/2011, at 1:10 PM, Jay Daley wrote:
4. We do not want to push the key size up to 2048 "just to be sure" because that imposes a greater DNS packet size and CPU cost for signature verification for end users of DNSSEC. We are also acutely aware that a TLD registry often sets a de facto standard followed by their registrars and registrants, which magnifies the impact of our choice.
I haven't read the rest of this post in detail but this caught my eye. I'm not sure that packet size is a problem when other registries are doing 2048bit. Same for sig verification for that matter - if 90% of registries are 2048bit, do we really save the world that much CPU? What's the CPU difference between no verification, 1280bit, and 2048bit? If it is for example 100 cycles to do no validation, 10000 for 1280bit validation, and 11000 for 2048bit validation, we're talking about a CPU step up of 100x or 110x. Seems pretty insignificant at that point - especially when most other registries are doing 2048bit, the difference between CPU required for .nz's decision between 1280 and 2048 gets even smaller.. -- Nathan Ward