VoIP protocols

This interactive voice response (IVR) diagram sample shows the Voice over IP (VoIP) signalling protocol stack. It was designed on the base of the Wikimedia Commons file: Pvoip.gif. [commons.wikimedia.org/ wiki/ File:Pvoip.gif]
This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. [creativecommons.org/ licenses/ by-sa/ 3.0/ deed.en]
"A VoIP phone or IP phone uses Voice over IP technologies for placing and transmitting telephone calls over an IP network, such as the Internet, instead of the traditional public switched telephone network (PSTN).
Digital IP-based telephone service uses control protocols such as the Session Initiation Protocol (SIP), Skinny Client Control Protocol (SCCP) or various other proprietary protocols." [VoIP phone. Wikipedia]
The IVR diagram example "VoIP protocols" was designed using ConceptDraw PRO diagramming and vector drawing software extended with the Interactive Voice Response Diagrams solution from the Computer and Networks area of ConceptDraw Solution Park.