glossary · term
TLS fingerprint (JA3/JA4)
A profile of TLS handshake parameters used to classify and correlate clients.
A TLS fingerprint is a profile of a client’s TLS handshake, including protocol versions, cipher suites, and extensions. JA3 and JA4 turn selected handshake attributes into identifiers useful for traffic classification and correlation. In multi-account environments, the TLS profile should be consistent with the claimed browser and network context because unusual differences may trigger additional scrutiny.
