User`s guide
Table Of Contents
- VMG8924-B10A and VMG8924- B30A Series
- User’s Guide
- Technical Reference
- Network Map and Status Screens
- Broadband
- Wireless
- Home Networking
- 7.1 Overview
- 7.2 The LAN Setup Screen
- 7.3 The Static DHCP Screen
- 7.4 The UPnP Screen
- 7.5 Installing UPnP in Windows Example
- 7.6 Using UPnP in Windows XP Example
- 7.7 The Additional Subnet Screen
- 7.8 The STB Vendor ID Screen
- 7.9 The 5th Ethernet Port Screen
- 7.10 The LAN VLAN Screen
- 7.11 The Wake on LAN Screen
- 7.12 Technical Reference
- Routing
- Quality of Service (QoS)
- Network Address Translation (NAT)
- Dynamic DNS Setup
- Interface Group
- USB Service
- Power Management
- Firewall
- MAC Filter
- Parental Control
- Scheduler Rule
- Certificates
- VPN
- Voice
- Log
- Traffic Status
- VoIP Status
- ARP Table
- Routing Table
- IGMP/MLD Status
- xDSL Statistics
- 3G Statistics
- User Account
- Remote Management
- TR-069 Client
- TR-064
- SNMP
- Time Settings
- E-mail Notification
- Logs Setting
- Firmware Upgrade
- Configuration
- Diagnostic
- Troubleshooting
- Customer Support
- Setting up Your Computer’s IP Address
- IP Addresses and Subnetting
- Pop-up Windows, JavaScripts and Java Permissions
- Wireless LANs
- IPv6
- Services
- Legal Information
- Index

Chapter 21 Voice
VMG8924-B10A and VMG8924-B30A Series User’s Guide
255
In the following example, you want to use client device A to call someone who is using client device
C.
1 Client device A sends a call invitation for C to the SIP redirect server (B).
2 The SIP redirect server sends the invitation back to A with C’s IP address (or domain name).
3 Client device A then sends the call invitation to client device C.
Figure 153 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.