Voice over IP protocol families
There are currently four families of VoIP protocols: SIP, H.323 and H.248 based, and SIGTRAN.
The call control protocols establish, modify and release connections.
Based on IETF specifications:
Sigcomp: "Signaling Compression " a solution for compressing messages generated by application protocols such as SIP and RTSP.
Based on ITU-T specifications:
H323: "Packet-based multimedia communications systems"
H225: "call control protocol"
H245: "Media control protocol"
H450: "Supplementary Services"
Q.931: "ISDN user-network interface layer 3 specification for basic call control"
H223: Multiplexing protocol for circuit-based multimedia communications system
Based on IETF and ITU-T specifications:
H248/MEGACO: "MEdia GAteway COntrol protocol" H248.1 version 3:
SIGTRAN is often used in connections towards PSTN.
Cisco proprietary protocols:
SKINNY: Terminal control protocol.
Digium proprietary protocols:
Nortel proprietary protocols:
UNISTIM: A stimulus protocol for IP phones.
T38: "Real-time facsimile (T.38), Fax-over-IP"
Movement toward secure communications involve these protocols
Authentication, Authorization and Accounting
As far as I know MGCP is a VoIP family too. So you should put MGCP + H248 in call control section.- Cedric MILLET