H.235 is an ITU -T recommendation of the International Telecommunication Union ( ITU) on security and encryption ( Electronics / Telecommunications / Multimedia ). It covers H.323 and H.245 -based terminals.

The standard includes authentication by means of various algorithms, including Diffie -Hellman key exchange, and data protection, which is achieved by encryption, even for the media channels.

The standardization committee agreed on H.235 Annex D as the minimum requirement for an H.235 -compliant implementation. This Appendix D, also known as Baseline Security Profile, defined authentication and integrity.

An appendix D -capable gatekeeper can thereby ensure that only trusted endpoints get granted access to the services of the gatekeeper.