TLS cipher suites: What “ECDHE … AES-256-GCM …” actually means
A compact explanation of modern TLS cipher suite components and what to look for.
Summary
Every TLS cipher suite string encodes four decisions: key exchange, authentication, bulk encryption, and message authentication. Reading the string tells you immediately whether forward secrecy or AEAD protection is in play.
Breaking down the parts
ECDHE signals an ephemeral elliptic-curve Diffie-Hellman exchange, which provides forward secrecy. The middle segment usually names the certificate authentication method (for example, RSA or ECDSA). The final entries such as AES-256-GCM and SHA384 describe the symmetric cipher and hash used for the AEAD tag.
Choosing suites
Prefer AEAD suites (GCM or CHACHA20-POLY1305) and drop legacy CBC or RC4 entries. MTAs typically advertise a short preference-ordered list so that remote clients settle on the most secure overlap. Monitor negotiation logs to confirm that the suites you intend to deprecate truly disappear from production sessions.
Operational guidance
Document minimum TLS versions in change control and publish guidance for partners that still operate TLS 1.0 stacks. Tie cipher choices back to your DANE deployment to make the security story coherent.
Further reading (German)
Keywords
TLS, ECDHE, AES-GCM, cipher suite, crypto