17-14
Cisco ASA Series Firewall ASDM Configuration Guide
Chapter17 Configuring the Cisco Phone Proxy
Configuring the Phone Proxy
•If you decide to configure a media-termination address on interfaces (rather than using a global
interface), you must configure a media-termination address on at least two interfaces (the inside and
an outside interface) before applying the phone-proxy service policy. Otherwise, you will receive an
error message when enabling the Phone Proxy with SIP and Skinny Inspection.
•The phone proxy can use only one type of media termination instance at a time; for example, you
can configure a global media-termination address for all interfaces or configure a media-termination
address for different interfaces. However, you cannot use a global media-termination address and
media-termination addresses configured for each interface at the same time.
Configuring the Phone Proxy
This section includes the following topics:
•Task Flow for Configuring the Phone Proxy, page17-14
•Creating the CTL File, page 17-15
•Adding or Editing a Record Entry in a CTL File, page17-16
•Creating the Media Termination Instance, page17-17
•Creating the Phone Proxy Instance, page17-18
•Adding or Editing the TFTP Server for a Phone Proxy, page17-20
•Configuring Linksys Routers with UDP Port Forwarding for the Phone Proxy, page17-21

Task Flow for Configuring the Phone Proxy

Note This feature is not supported for the Adaptive Security Appliance version 8.1.2.
Configuring the Phone Proxy requires the following steps:
Step 1: Create the CTL file. See Creating the CTL File, page17-15.
Step 2: Create the TLS Proxy instance to handle the encrypted signaling. See Adding a TLS Proxy
Instance, page 18-9.
Step 3: Create the Phone Proxy instance. See the “Creating the Phone Proxy Instance” section on
page 17-18.
Step 4: Configure the media termination address for the Phone Proxy. See Creating the Media
Termination Instance, page17-17.
Note Before you enable SIP and Skinny inspection for the Phone Proxy (which is done by applying the Phone
Proxy to a service policy rule), the Phone Proxy must have an MTA instance, TLS Proxy, and CTL file
assigned to it before the Phone Proxy can be applied to a service policy. Additionally, once a Phone
Proxy is applied to a service policy rule, the Phone Proxy cannot be changed or removed.
Step 5: Enable the Phone Proxy with SIP and Skinny inspection. See SIP Inspection, page12-20 and
Skinny (SCCP) Inspection, page12-32.