AltiGen comm ACM 5.1 - Manual (Page 331)

Chapter 24: Network Configuration Guidelines for VoIP
AltiWare ACM 5.1 Administration Manual 317
Network Configuration Guidelines for AltiGen IP
Phones
The following guidelines (specific to AltiGen IP phones) should be taken into
consideration before you configure your network for use with NAT.
• DHCP is recommended to reduce the risks for duplicating IP addresses. AltiWare
ACC/ACM provides seamless support for AltiGen IP phones using dynamic IP
addresses. Select Dynamic IP address for IP Extensions in the AltiWare
Administrator’s Extension Configuration window.
• A switch is recommended at the corporate network, rather than a hub, for IP phone
connection. This can reduce packet loss ratio.
•
If DHCP is used in this configuration, the administrator will need to perform the
following for the AltiGen IP phone:
1.
Configure the DHCP server to assign a private network IP address for each
phone based on the phone’s MAC address (printed on the label on the bottom
of the IP phone).
2. Add the private IP address to AltiServ and the TFTP server.
Configuration Guidelines for NAT
Note: This section only applies to AltiGen IP phones or IPTalk integrated with AltiView/
AltiAgent.
The section discusses the configuration guidelines when AltiServ is behind NAT (Network
Address Translation) and communication to AltiGen IP phones, IPTalk, or another
AltiServ is over WAN. AltiGen SIP phones support NAT traversal, which does not require
special settings on the NAT router at the remote site.
Due to H.323/SIP protocol, which puts the IP address information in the TCP/IP payload,
the NAT router requires some H.323 protocol and SIP protocol implementation to
correctly handle the H.323/SIP traffic and translate the private IP address into a public
IP address. Not all NAT routers have this kind of implementation. If the NAT router does
not support H.323/SIP, you need to check Enable SIP NAT support and Enable H323
NAT support in AltiEnterprise Manager, IP Networks tab.
The following sections illustrate a private network configuration and a VPN configuration.
For information on setting up VoIP traffic forwarding for NAT and configuring AltiServ
behind NAT, see “Configuring AltiServ Behind NAT” on page 335.
Private Network Configuration Example
(AltiWare with private IP address and behind NAT)
Only the private IP address is used in a private network—the public router will not route
the packet that has a private IP address as its destination. (All IP addresses beginning
with 192.168.x.x, 10.x.x.x, or 172.16.x.x to 172.32.x.x are private IP addresses.)