D-Link NetDefendOS User Manual page 473

4. Click OK
E. Define the IP Policy for incoming SIP traffic:
1. Go to: Rules > IP Rule Set > main > Add > IP Policy
2. Now enter:
• Name: sip_allow
• Action: Allow
• Source Interface: ext
• Source Network: proxy_ip
• Destination Interface: core
• Destination Network: ip_wan
• Service: my_sip_service
• Comment: Allow incoming SIP traffic
3. Select the VoIP tab, enable VoIP and select my_sip_profile
4. Click OK
Scenario 2
Protecting proxy and local clients - Proxy on the same network as clients
In this scenario the goal is to protect the local clients as well as the SIP proxy. The proxy is located
on the same, local network as the clients, with SIP signaling and media data flowing across two
interfaces. This scenario is illustrated below.
This scenario can be implemented in two ways:
• Using NAT to hide the network topology.
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Chapter 6: Security Mechanisms