Chapter 15 Voice
Client device A then sends the call invitation to client device C.
3
Figure 97 SIP Redirect Server
SIP Register Server
A SIP register server maintains a database of SIP identity-to-IP address (or
domain name) mapping. The register server checks your user name and password
when you register.
RTP
When you make a VoIP call using SIP, the RTP (Real time Transport Protocol) is
used to handle voice data transfer. See RFC 1889 for details on RTP.
Pulse Code Modulation
Pulse Code Modulation (PCM) measures analog signal amplitudes at regular time
intervals and converts them into bits.
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Basic Home Station VDSL2 P8802T User's Guide