3Com S200 Switch User Manual


 
Voice Over IP 5
T0008-48/B Revision 5.2
About Voice over IP (VoIP)
Establishing a Call
Introduction This section describes call establishments. Figure 4 shows the packets exchanged for
session and connection establishment and finally, voice transfer.
Figure 4. Session and Connection Establishment
Voice Port Voice Port
ACP call request
TCP call request
TCP Call accept
SoTCP internal call request
ACP call request
ACP call accept
SoTCP internal call accept
ACP call accept
Source IP Node Destination IP Node
Session Setup
Connection Setup
Voice
Voice
Voice
Data Transfer
Open UDP channel