ACME
The protocol Let's Encrypt uses to issue and renew TLS certificates automatically.
Definition
Automatic Certificate Management Environment (ACME) is an IETF protocol for proving domain control and obtaining TLS certificates without a human signing CSRs. Let's Encrypt is the dominant ACME CA; certbot, Caddy, Traefik, and nginx-proxy-manager are common clients. Most modern reverse proxies handle ACME renewal automatically, eliminating expired-cert outages.
When to use
See also
- TLS — The protocol that encrypts HTTP and other connections — what the lock icon in browsers actually means.
- Caddy — Modern reverse proxy and web server with automatic HTTPS via Let's Encrypt — a simpler alternative to nginx.