What is TLS?
TLS (Transport Layer Security) is the cryptographic protocol that secures internet communications, succeeding SSL. It encrypts data transmitted between a web browser and server, ensuring privacy, data integrity, and authentication. Modern HTTPS connections use TLS 1.2 or TLS 1.3.
How Does TLS Work?
TLS works through a handshake process: the client and server agree on a protocol version, select cipher suites, authenticate via certificates, and establish encrypted session keys. TLS 1.3, the latest version, simplified this handshake to a single round trip, significantly improving connection speed while maintaining strong security.
Although people often say "SSL certificate," modern certificates actually use TLS. SSL (versions 1.0-3.0) has been deprecated due to security vulnerabilities. When setting up HTTPS hosting, you install a TLS certificate (still marketed as SSL) from a Certificate Authority. Free certificates from Let's Encrypt have made TLS encryption accessible to every website.