On 3/14/19 12:38 PM, Michael Richardson wrote:
If keys are generated a few years in advance of going into active use, there is plenty of time for them to be disseminated beforehand. They do not have to be pre-published in the zone (although that is what RFC 5011 was designed for); they can be distributed out of band by software updates or other means. If there are annual rollovers with keys generated N years in advance, at any time there will be N pre-published keys one of which might be pre-published in the zone, one active KSK in production, and maybe one in retirement.
Yes, I'd like to do that. I'd like N=10, and the roll-over frequency to be yearly.
The problem with generating that many keys out into the future is they then become hostages to fortune should any issues arise during that time-span with the integrity of those keys. e.g. a breach which causes the private keys to be disclosed, flaws being discovered in the algorithm in use, or the processes used to generate the keys, etc. Which would likely mean a complete reset for new keys to be generated, and a very large pile of baked-in pre-disseminated keys needing revoked. The overall approach and annual rollover makes sense to me, but I think care needs to be taken with the numbers proposed. Keith