scope:

Transport layer security (TLS) is a cryptography protocol that provides secure communication between two IP transport connection endpoints This Recommendation defines, in general, ITU-T H.248 signalling elements for support of TLS in various options.

This Recommendation provides, in more detail, information about:

- basic exchange architecture of keying information between the control plane (including ITU-T H.248 interface) and the bearer plane;

- negotiation aspects: indication and determination of cryptographic capabilities between TLS endpoints;

- minimum amount of information carried by ITU-T H.248 for establishing ITU-T H.248 TLS/L4 terminations (Note);

NOTE - Some information could be provisioned via management and there is also TLS information exchanged via the (L4) bearer interface with the remote TLS endpoint.

- TLS procedures in detail at the various TLS sublayers, i.e., for support of the:

• TLS record protocol,
• TLS handshake protocol,
• TLS change cipher spec protocol,
• TLS alert protocol, TLS application data protocol;

- profiling of TLS services;

- specifying a set of cipher suites;

- consideration of ITU-T H.248 MG modes of operation and connection models; and

- SDP- versus Property-based TLS endpoint control.

The scope of this Recommendation is limited to the TLS protocol (the DTLS partner protocol is subject of another Recommendation).