I agree with the eggs/basket argument, though I suppose there's an argument to be made about a number of CAs being essentially too big to fail already, so what's one more?
Regarding client certificates: There aren't really many good reasons to use publicly-trusted certificates for client authentication, but if you insist, you can use Let's Encrypt for that. The certificates do have the id-kp-ClientAuth EKU.
I think it would be nice to move toward having a lot of medium-sized nonprofit CAs instead of a handful of crappy commercial ones, which is the current situation.
"Too big to fail" is the problem with the current CA system, and today's well-run TBTFCA is tomorrow's global security crisis.
OMG yes on wildcard certs! My company has multiple domains and uses subdomains for every affiliate and we have thousands of affiliates. One *.example.com cert per domain and we're good to go. Now if only we could get IIS to support multi-domain wildcard certs so we could get all of our domains and subdomains under one master cert I'd be in heaven! (SNI doesn't work for us b/c ~12% of our traffic still uses IE7 or earlier).
So why not buy one now? I get the excitement about simple certification process, free access and refresh, etc. But if you have thousands of affiliates, current wildcard cert providers should offer a pretty good solution. Is anything missing there? I mean, if we ignore the idea why LE is good in general, $100 / year is nothing if you actually need a wildcard.
Oh we absolutely do just buy them now through RapidSSL. It's all of those other reasons I wish LE supported them. I wouldn't mind paying LE for them, I want an API for requesting them, a simpler certification process, and easier refreshes.
I don't get the desire for longer-life certs. I would argue that they should be shorter to keep the exposure of a leaked cert down. Whether a cert is good for a week or a year you should be automating the renewal.
Same as EFF/Mozilla. Let's Encrypt hasn't fulfilled their goal until everyone can get free HTTP encryption.
As a user, if I have to wait 24 hours (or more, depending on queue depth) for a Let's Encrypt batch queue to be processed after I sign up for some free blogging platform before I can use an assigned subdomain, then I'm probably going to close my tab and never come back. Let's Encrypt hasn't fulfilled its goal until this doesn't happen any more. This batch queuing model is necessary so that sites don't exceed the Let's Encrypt daily quota.
Some applications rely on wildcard subdomains, and require a wildcard certificate to be instantly responsive.
To anyone thinking "just don't use encryption until after the cert has been provisioned"—not going to work if you use HSTS. Your users have to wait all day before they can use their subdomain.
This sounds more like a design decision by that blogging platform rather than something that's caused by Let's Encrypt. Excluding maintenance windows or any other unplanned downtime or performance issues (which happen relatively rarely), the issuance process doesn't take anywhere near close to 24 hours. Account registration, domain validation and certificate issuance is typically done in less than ten seconds.
The existing rate limits[1] should have very little effect even for very large integrators. A form for rate limit adjustments exists for those who need a large number of subdomains (and would rather not obtain a wildcard certificate) or need to add new domains at a very high rate (i.e. the WordPress.com's and OVH's of this world).
Edit: The document you linked to was recently updated, but the top of the page incorrectly says "Last updated: August 10, 2016". I wrote my response with the old document in mind. It's obvious to me now that this page was actually last updated in December 2016.
If I don't batch multiple SANs into one certificate and stagger a certificate queue, I will very quickly run into the Let's Encrypt rate limit.
If I don't want my users to wait for the queue to be processed, I could immediately request a new certificate for every new user's subdomain, but then I'd be limited to 10 new users every 3 hours.
I assume by "multiple SANs", you're referring to subdomains under the same registered domain? In that case, you can use the rate limit adjustment form or register your domain as a public suffix if that's more appropriate. The form has been available since August. The rate limits in general have not changed since back then (or even before, I don't recall) either.
Obviously LE employs a handful of people, and they are in some ways an "advertisement" for Mozilla (not that it's a bad thing). Those alone are some reasons why something might want to be attempted.
But I'm not necessarily thinking of a standalone "free certificate company" but maybe more of a "bonus" to some other product or service.
Think something like a domain host providing certificates themselves (which IMO makes a hell of a lot of sense).
> But I'm not necessarily thinking of a standalone "free certificate company" but maybe more of a "bonus" to some other product or service.
This is what I expect we'll see more of, rather than a second (and perhaps slightly different) Let's Encrypt. Major cloud providers will probably add their own variants of what Amazon offers with AWS Certificate Manager (ACM); more CDNs will start offering one-click SSL (like Cloudflare); "traditional" web hosting providers and control panel vendors will (hopefully) support SSL by default (like cPanel with AutoSSL, which supports Comodo and Let's Encrypt).
Yeah, and I'm also hoping they will gravitate toward more "standard" interfaces like you touched on at the end there.
With the help of Let's Encrypt and through some cooperation, we could make easily "pluggable" SSL cert providers where you can choose who you want with the click of a button.
I think it's fairly likely we'll see a number of CAs adding ACME support at some point. Judging by participation on the ACME mailing list, there seems to be interest from (at the very least) DigiCert, Entrust and cough StartSSL. I guess most of them will want to wait for the standardization process to finish before announcing any plans.
What would be the motivation for a competitor?