Did you know?

This SDK was used to build:

Ozeki Phone System XE - VoIP PBX Software for Developers Which is a high performance PBX system supporting Mobile and Desktop phones.


It was also used to create Ozeki 3D VoIP softphone. A cool SIP client that allows 3D Video calls.

Protocols for VoIP connection

To be able to provide VoIP services several protocols need to be employed. On this page we focus on the four most common ones used to describe VoIP connections.

Protocol is a generic term, a standard that describes how the respective participants communicate with each other. For transmitting audio and video packets between communicating computers Real-Time Protocol (RTP) is used worldwide. But before audio or video media are transmitted between computers other protocols need to be used to find the remote device and to define the means by which media will be transmitted between the two devices. These are call-signaling protocols, such as Session Initiation Protocol (SIP).

VoIP connections are basically described with the following protocols: