DevOps Dictionary

SSL (Secure Sockets Layer) is the older name for the encryption protocol used to secure traffic between a browser (or API client) and a server; in modern systems it’s implemented as TLS, but “SSL” is still commonly used to describe the same protection. It prevents eavesdropping and tampering by establishing an encrypted channel and authenticating the server’s identity using a certificate, so clients can trust they’re talking to the intended site. During the initial handshake, the client and server negotiate cryptographic settings and derive shared session keys that then encrypt and integrity-check the data in transit.

With SSL/TLS, credentials, cookies, and sensitive payloads are unreadable and difficult to modify on the network path; without it, traffic can be intercepted, altered, or replayed, leading to account compromise and data leakage. This gap exists because only the endpoints that possess the negotiated keys can decrypt and validate the messages.