48-27
Cisco ASA 5500 Series Configuration Guide using the CLI
Chapter48 Configuring the Cisco Phone Proxy
Troubleshooting the Phone Proxy

Configuring Your Router

Your firewall/router needs to be configured to forward a range of UDP ports to the IP phone. This will
allow the IP phone to receive audio when you make/receive calls.
Note Different Cable/DSL routers have different procedures for this configuration. Furthermore most
NAT-capable routers will only allow a given port range to be forwarded to a single IP address
The configuration of each brand/model of firewall/router is different, but the task is the same. For
specific instructions for your brand and model of router, please contact the manufacturer’s website.
Linksys Routers
Step1 From your web browser, connect to the router administrative web page. For Linksys, this is typically
something like http://192.168.1.1.
Step2 Click Applications & Gaming or the Port Forwarding tab (whichever is present on your router).
Step3 Locate the table containing the port forwarding data and add an entry containing the following values:
Step4 Click Save Settings. Port forwarding is configured.
Troubleshooting the Phone Proxy
This section includes the following topics:
Debugging Information from the Security Appliance, page48-27
Debugging Information from IP Phones, page48-31
IP Phone Registration Failure, page48-32
Media Termination Address Errors, page48-40
Audio Problems with IP Phones, page48-41
Saving SAST Keys, page48-41

Debugging Information from the Security Appliance

This section describes how to use the debug, capture, and show commands to obtain debugging
information for the phone proxy. See the command reference for detailed information about the syntax
for these commands.
Table48-4 lists the debug commands to use with the phone proxy.
Table48-3 Port Forwarding Values to Add to Router
Application Start End Protocol IP Address Enabled
IP phone 1024 65535 UDP Phone IP address Checked
TFTP 69 69 UDP Phone IP address Checked