Triple-Play Service Deployment

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Control plane protocols
Real Time Control Protocol (RTCP) allows the end points to
communicate directly concerning the quality of the RTP packet
stream. RTCP gives the end-points the ability to adjust the call in
real time to increase its quality.
The control plane provides signaling protocols that register VoIP
phones and connect phone calls among other functions. H.323
was the first widely adopted and deployed VoIP protocol suite.The
standard was developed by the International Telecommunications
Union’s Telecommunication Standardization Sector (ITU-T) for
transmitting audio and video over the Internet. Over the last 10
years this protocol has gone through several revisions and
additions to provide more features and increase scalability and
stability. H.225 is the media control portion of the H.323 protocol
suite. It establishes a logical channel for each call. H.225 represents
the basic signaling messages including setup, alerting, connect,
call proceeding, release complete, and facility messages.
H.245
TCP UDP
IP
Figure 8.2 H.323 protocol stack
H.225
Call Control
RAS RTP
Chapter 8: Troubleshooting VoIP
Voice
RTCP