Using The H.323 Alg In A Corporate Environment - D-Link DFL-260E User Manual

6.2.9. The H.323 ALG
2. Now enter:
• Name: H323Out
• Action: NAT
• Service: H323-Gatekeeper
• Source Interface: lan
• Destination Interface: any
• Source Network: lannet
• Destination Network: 0.0.0.0/0 (all-nets)
• Comment: Allow outgoing communication with a gatekeeper
3. Click OK
Example 6.10. Using the H.323 ALG in a Corporate Environment
This scenario is an example of a more complex network that shows how the H.323 ALG can be deployed in a
corporate environment. At the head office DMZ a H.323 Gatekeeper is placed that can handle all H.323 clients in
the head-, branch- and remote offices. This will allow the whole corporation to use the network for both voice
communication and application sharing. It is assumed that the VPN tunnels are correctly configured and that all
offices use private IP-ranges on their local networks. All outside calls are done over the existing telephone
network using the gateway (ip-gateway) connected to the ordinary telephone network.
Note: Outgoing calls do not need a specific rule
There is no need to specify a specific rule for outgoing calls. NetDefendOS monitors
the communication between "external" phones and the Gatekeeper to make sure that it
is possible for internal phones to call the external phones that are registered with the
gatekeeper.
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Chapter 6. Security Mechanisms