SSL articles
Articles on SSL/TLS certificates: expiry, rotation, automation, and monitoring so a lapsed cert never takes you offline.
Monitoring certificates when they rotate weekly
When certificates rotate every few weeks, 'alert 30 days before expiry' is meaningless. The monitoring model has to flip from expiry countdown to rotation health: did the cert actually change, on every endpoint, with the right chain? Here's what to watch instead.
Kevin Langley Jr 9 min readMerkle Tree Certificates explained
Post-quantum signatures threaten to bloat every TLS handshake by kilobytes. Merkle Tree Certificates are the clever fix: batch thousands of certificates into a tree, sign one root, and ship a tiny proof instead of a giant signature. Here's how they work, why they're so much smaller, and where they fit.
Kevin Langley Jr 9 min readPost-quantum TLS migration: you're probably already doing it
Post-quantum key exchange is already in a third of real HTTPS traffic and most operators never noticed. What X25519MLKEM768 actually changes, why 'harvest now, decrypt later' makes key exchange urgent today, and a practical migration path — plus the half of the problem nobody has solved yet.
Kevin Langley Jr 9 min readACME + ARI: automation that survives 47-day certificates
Surviving short-lived certificates means renewal automation that never blinks. A deep dive into ACME's challenge types and the ARI extension (RFC 9773) — how CAs now tell your client exactly when to renew, how to avoid thundering herds, and how mass revocation stops being a fire drill.
Kevin Langley Jr 11 min readThe 47-day certificate era
Public TLS certificate lifetimes are collapsing: 200 days today, 100 in 2027, 47 by 2029. Here's the schedule, why it's happening, and what an 8x jump in renewal frequency actually changes for the teams who run certificates.
Kevin Langley Jr 10 min readYour SSL certificate is about to expire: a calm checklist
An expired TLS certificate throws a full-page security warning and can take a site down outright. Here's what to check, and how to stop it from happening by surprise.
Kevin Langley Jr 2 min read