I wish root programs accepted roots from new CAs at a speed where a one year old dictionary would be a problem. Cross-certificates are already generally required for several years, on average. However, cross-certificates are not ideal, as they increase server configuration problems and chain length, which as we've been discussing sometimes has performance impacts.
It's something I wish the industry would fix, and I'm glad that improvements in this area are getting discussed again at CABF. But yes, we should be careful that we do not introduce a new mechanism that would potentially add a new bottleneck to root ubiquity, even if it isn't and won't be the long pole today. Because we don't want it to become the long pole in the future as the ecosystem continues to improve. -Tim > -----Original Message----- > From: TLS <tls-boun...@ietf.org> On Behalf Of Kampanakis, Panos > Sent: Wednesday, July 12, 2023 9:31 PM > To: Dennis Jackson <ietf=40dennis-jackson...@dmarc.ietf.org>; TLS List > <tls@ietf.org> > Subject: Re: [TLS] Abridged Certificate Compression (dictionary versioning) > > I wish there was a study of the certs issued by newly introduced CAs in CCADB > and how quickly they ramp up. I am concerned that a 1 year old dictionary > could end up slowing down a good amount of destinations. But again, that > slowdown does not mean an outage. And servers could ensure they get their > certs issued or cross-issued by relatively mature CAs if they do not want PQ > Sig > related slowdowns. > > Btw, in 3.1.1 I noticed > - "Remove all intermediate certificates which are not signed by root > certificates > still in the listing." > > That could eliminate some 2+ ICA cert chains. Any reason why? > > > > -----Original Message----- > From: Dennis Jackson <ietf=40dennis-jackson...@dmarc.ietf.org> > Sent: Wednesday, July 12, 2023 1:01 PM > To: Kampanakis, Panos <kpa...@amazon.com>; TLS List <tls@ietf.org> > Subject: RE: [EXTERNAL][TLS] Abridged Certificate Compression (dictionary > versioning) > > CAUTION: This email originated from outside of the organization. Do not click > links or open attachments unless you can confirm the sender and know the > content is safe. > > > > On 12/07/2023 04:54, Kampanakis, Panos wrote: > > > Hi Dennis, > > > > Appendix B.1 talks about 100-200 new ICA and 10 Root certs per year. In > the past I had looked at fluctuations of CCADB and there are daily changes. > When checking in the past, I did not generate the ordered list as per pass 1 > on > a daily basis to confirm it, but I confirmed the fluctuations. The commits in > https://github.com/FiloSottile/intermediates/commits/main show it too. > Given that, I am wondering if CCADB is not that stable. Are you confident that > ICA dictionaries (based on CCADB) won't materially change often? > > I checked the historical data for the last few years to ballpark a rate of > 100-200 > new intermediates per year. A uniform distribution of arrivals would mean 2 to > 4 changes a week, which matches Filippo's commit frequency [1]. In practice > Filippo's commits include removals (which we don't care about) and batched > additions (which we do), but the numbers seem about right. > > In terms of impact, the question is how much usage do those new ICAs see in > their first year. If we expect websites to adopt them equally likely as > existing > ICAs then they should make up <5% of the population. I think in practice they > see much slower adoption and so the impact is even lower, for example a > reasonable proportion are vanity certificates with limited applicability or > intended to replace an existing cert in the future. If we wanted to confirm > this > we could build the abridged cert dictionaries for '22 and then use CT to > sample > the cert chains used by websites that year. I'll see if I can find the time > to put > that together. > > If there was an appetite for a faster moving dictionary, we could use the > scheme I sketched in the appendix to the draft. But I think we should try to > avoid that complexity if we can. > > Best, > Dennis > > [1] https://github.com/FiloSottile/intermediates/graphs/commit-activity > > _______________________________________________ > TLS mailing list > TLS@ietf.org > https://www.ietf.org/mailman/listinfo/tls _______________________________________________ TLS mailing list TLS@ietf.org https://www.ietf.org/mailman/listinfo/tls
