RTP and H.323 for IP Telephony
RTP and H.323 for IP Telephony
|
audio/video applications |
signaling and control |
data applications |
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|
video code |
audio codec |
RTCP |
H.225 registration |
H.225 Signaling |
H.245 Control |
T.120 |
|
RTP |
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| UDP |
TCP |
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|
IP |
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|
H.323 |
framework of a group protocols for IP telephony (from ITU) |
|
H.225 |
Signaling used to establish a call |
|
H.245 |
Control and feedback during the call |
|
T.120 |
Exchange of data associated with a call |
|
RTP |
Real-time data transfer |
|
RTCP |
Real-time Control Protocol |
We will not examine H.323 in much detail, but will examine RTP and RTCP.
Transcript
[slide78] So, how does it fit together into [the} protocol stack? We can see up here that we have IP with UDP and TCP on top of it. We have the media stream sitting on top of RTP with a video CODEC or audio CODEC. We have signaling carried over a protocol called RTCP, the real time control protocol associated with RTP. Or we could use another signaling and control protocol like H.225 for registration protocol, or on top of TCP, an H.225 signaling, or an H.245 control, or a T.120 for data. So a whole variety of different protocols that we can use. But in general, we're sending media on top of UDP, and we're sending the other traffic for signaling across TCP.