Cisco WRP400-G1 Administration Guide - Page 27

Configuring Your System for ITSP Interoperability Configuring NAT Mapping 2 STEP 6 Click Save Settings. NOTE You also need to configure the firewall settings on your router to allow SIP traffic. See "Firewalls and SIP," on page 26. Determining Whether the Router Uses Symmetric or Asymmetric NAT To use a STUN server, the edge device-that is, the device that routes traffic between your private network and your ISP network-must have an asymmetric NAT mechanism. You need to determine which type of NAT mechanism is available on that device. STUN does not work on routers with symmetric NAT. With symmetric NAT, IP addresses are mapped from one internal IP address and port to one external, routable destination IP address and port. If another packet is sent from the same source IP address and port to a different destination, then a different IP address and port number combination is used. This method is restrictive because an external host can send a packet to a particular port on the internal host only if the internal host first sent a packet from that port to the external host. NOTE This procedure assumes that a syslog server is configured and is ready to receive syslog messages. STEP 1 Make sure you do not have firewall running on your computer that could block the syslog port (port 514 by default). STEP 2 Start Internet Explorer, connect to the Configuration Utility, choose Voice > Admin Login. If prompted, enter the administrative login provided by the Service Provider. (The default username and password are both admin.) STEP 3 To enable debugging, complete the following tasks: a. Under the Voice menu, click System. b. In the Debug Server field, enter the IP address of your syslog server. This address and port number must be reachable from the WRP400. Cisco Small Business WRP400 Administration Guide 25