Which protocol does the IPO use for secure communications?

The IPO (IP Office) uses SRTP (Secure Real-time Transport Protocol) for secure communications, particularly for voice and video transmission over IP networks. SRTP enhances the security of real-time audio and video streaming by providing encryption, message authentication, and replay protection.

While HTTP is used for transferring hypertext documents and SIP is primarily responsible for initiating, maintaining, and terminating real-time sessions, they do not specifically offer the same level of security for media streams as SRTP does. FTP is focused on transferring files between devices and also lacks the necessary security features required for real-time communications. Thus, SRTP stands out as the most appropriate protocol for ensuring secure real-time communications in the context of the IPO.