ZyXEL LTE5121 User Guide - Page 182

SIP Register Server, Pulse Code Modulation, SIP Call Progression

Page 182 highlights

Chapter 17 VoIP 3 Client device A then sends the call invitation to client device C. Figure 120 SIP Redirect Server 1 3 A 2 B C 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 3550 for details on RTP. Pulse Code Modulation Pulse Code Modulation (PCM) measures analog signal amplitudes at regular time intervals and converts them into bits. SIP Call Progression The following figure displays the basic steps in the setup and tear down of a SIP call. A calls B. Table 76 SIP Call Progression A B 1. INVITE 2. Ringing 3. OK 4. ACK 6. BYE 5. Dialogue (voice traffic) 7. OK 182 LTE-5121 User's Guide

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Chapter 17 VoIP
LTE-5121 User’s Guide
182
3
Client device
A
then sends the call invitation to client device
C
.
Figure 120
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 3550 for details on RTP.
Pulse Code Modulation
Pulse Code Modulation (PCM) measures analog signal amplitudes at regular time intervals and
converts them into bits.
SIP Call Progression
The following figure displays the basic steps in the setup and tear down of a SIP call. A calls B.
Table 76
SIP Call Progression
A
B
1. INVITE
2. Ringing
3. OK
4. ACK
5. Dialogue (voice traffic)
6. BYE
7. OK
1
2
3
A
B
C