The purpose of this Recommendation is to provide recommendations of security procedures for using direct‑routed call signalling in conjunction with H.235.1 and H.235.3 security profiles. This security profile is offered as an option and may complement the security profiles in ITU-T Recs H.235.1 and H.235.3. It also provides implementation details for clause 8.4/H.235.0 using symmetric key management techniques.

In earlier versions of the H.235 subseries, this profile was contained in Annex I/H.235. Appendices IV, V, VI to H.235.0 show the complete clause, figure, and table mapping between H.235 versions 3 and 4.