Security
SSL/TLS
Secure Sockets Layer / Transport Layer Security
SSL/TLS is the cryptographic protocol that secures HTTPS connections. It encrypts traffic between browser and server, authenticates the server's identity via a certificate, and ensures message integrity. SSL is the deprecated name; modern deployments use TLS 1.2 or TLS 1.3.
Part of SSL certificate monitoring — the full answer, the facts and the alternatives in one place.
In depth
Each HTTPS site presents a certificate signed by a trusted Certificate Authority (CA). Browsers verify the signature chain and reject connections to expired, mismatched, or unsigned certificates with a full-screen warning that destroys conversion rate.
Certificates have expiry dates (typically 90 days for Let's Encrypt, 1-2 years for paid CAs). Forgetting to renew is one of the most common causes of preventable downtime — even at large companies.
Why it matters
An expired certificate makes a site appear broken to every visitor. Monitoring certificate expiry with multi-week lead time, plus alerting on TLS configuration regressions (weak ciphers, missing OCSP stapling), is essential for any production site.
How Lemwatch helps with ssl/tls
Lemwatch monitors ssl/tls continuously and alerts you the moment something changes.
SSL monitoring →Related terms
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Browse the full Lemwatch monitoring glossary (47 terms).