Why is it called ZRTP?

Well, I’d rather not have to use the unwieldy acronym for Media Path Key Agreement for Secure RTP, which is descriptive because it negotiates the session keys for SRTP , Secure Real-time Transport Protocol (RFC 3711). . It was Alan Johnston who suggested ZRTP, a regrettably less descriptive mutation incorporating my last initial, and I used that instead. In defense of my immodesty, it’s worth noting that in the crypto community, eponymous crypto protocols are very much the norm. Examples include RSA , Diffie-Hellman, ElGamal, CAST , RC2 and RC4 (Ron’s Code), Blakely-Shamir, and many others.
Alan’s rationale for the name ZRTP also was based on the fact that ZRTP was originally (in its first couple of Internet drafts) based on adding header extensions to RTP packets, so ZRTP was really a variant of RTP. We have since changed the packet format to no longer encapsulate the ZRTP packets inside RTP header extensions, but to make them into a separate packet format that is distinguishable from RTP. In view of that change, ZRTP is now a pseudo-acronym.

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  • 12-Jun-2017