Altigen AltiContact Manager Version 5.0, Administration Manual

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Network Configuration Guidelines for VoIP
9-10 AltiContact Manager Administration Manual
• If you have heavier data applications running concurrently, the
bandwidth reserved for data traffic should be increased.
• If your router supports multilink or TCP fragmentation, configure your
WAN router to user smaller packet sizes, e.g. 500 bytes.
WAN Router Configuration
• The router which connects your LAN and the WAN should support
priority queuing.
• Configure the router so that the IP/UDP packets being sent to and from
an IP station have higher priority than the packets generated by other
stations on the same network. Please consult your router manufacturer
for more information on setting up this configuration.
Firewall Configuration
Please note the following very important guidelines when working with a
firewall on your network:
• If a firewall is used to protect your network access security,
reconfigure the firewall (as described in “Firewall Considerations” on
page 9-27) to open up TCP and UDP ports to the IP system’s IP
address. This allows IP’s voice and H.323 packets to pass through the
firewall freely. If the firewall supports H.323 protocol, configure the
firewall using H.323 instead of opening up the specific ports.
• Ensure that the rules to permit IP’s H.323 traffic are at the beginning
of your access filter list. This will minimize the delay of latency-
sensitive voice packets. This is ESPECIALLY important with long
access lists and/or slow routers.
Network Using NAT
If you plan to connect to your AltiContact Manager system via the
Internet and your router or Internet access provider is using Network
Address Translation (NAT), please note that most NAT
implementations DO NOT support H.323.
• You are probably using NAT if both of the following conditions
apply:
— Your AltiContact Manager server's IP address matches any of
the following numbers (where x is any number from 0-255):
• 10.x.x.x