Summary

Recommendation ITU-T H.235.6 holds the security procedures for the voice encryption profile (formerly in Annex D of Recommendation ITU-T H.235) including the accompanying native H.235/H.245 key management. Amendment 1 adds support for cipher key lengths of 192 and 256 bits to the advanced encryption standard (AES), the use of which is described in this Recommendation, along with additional Diffie-Hellman groups.

In earlier versions of the H.235 sub-series, this profile was contained in the main body of Recommendation ITU-T H.235 and of its Annex D. Appendices IV, V, VI to H.235.0 show the complete clause, figure, and table mapping between H.235 versions 3 and 4.