Cisco Small Business Voice Systems (Linksys Business Series)

Below are the parameters you need to check if you can't make outbound calls from SPA-942.

Step 1:
Verify the complete network connection.  If the SPA-942 is connected to an SPA-9000, make sure that the VoIP account is properly configured on the SPA-9000.  Since the SPA-9000 automatically provisions SPA942, you don't need to configure the settings on the SPA-942.  If the SPA-942 is registered directly to your VoIP provider, make sure that the username and password is properly configured on the device.  Verify also the Proxy and Outbound Proxy (if the VoIP provider requires Outbound Proxy).

Parameters to Check on SPA9000

Step 2:
Under Line tab of the SPA9000, look for Subscriber Information check if you have the right User ID and Password.

Step 3:
Under Info tab, check for Line 1-4 Status at least one of these lines should show that Registration State is Registered.

Parameters to Check on SPA9XX Series Phone

Step 1:
Check your SPA9XX IP Address. For more detailed information click here .

Step 2:
Launch your browser and type in  http://IP_Address_of_your_SPA9XX  on the address field then hit Enter.

You're now ready to configure the SPA9XX for NAT. If the web interface is asking for a username and password, this means that the unit was locked by your Provider. Please contact your respective VoIP Provider for assistance.

Enabling NAT Support Settings

You can set NAT Mapping Enable and NAT Keep Alive Enable to "Yes" under EXT1 tab of the SPA then click on .

Alternatively, if the SIP server registering the SPA9XX supports NAT, you can use Outbound Proxy configuration of the SPA to connect to it.

SPA product also supports STUN (Simple Traversal of UDP through NAT (Network Address Translation)) protocol. Under SIP tab, look for NAT Support Parameters. On STUN Server field place your STUN server address, set Substitute VIA Addr and STUN Enable to "Yes". Place your WAN IP address on EXT IP, then click on .

Note: STUN will not work if you have a symmetric NAT. If you enable the debug through syslog, and set STUN Test Enable" to "Yes" the SPA product will print information about whether or not you have a symmetric NAT.

On your NAT, you need to unblock UDP ports 5060, 5061, and the port range from 16384-16482. You ,you might also need to disable "SPI" if there is such function in your firewall.