Core Issue
Cisco 7960 IP phones can support either the skinny protocol or the Session Initiation Protocol (SIP), though not simultaneously. To determine the supported protocol, load different firmware versions on bootup. This functionality is transparent to the end user, and it is enabled by changes to the basic text-based configuration files that the phones download from a TFTP server.
Resolution
Before starting the SIP conversion, make sure the phone is running a firmware version of at least AL or higher. If this is not loaded, the firmware must first be upgraded through Cisco CallManager.
Download the following files from Cisco.com, and place them in the root directory of your TFTP server:
- Rename the SIPDefaultGeneric.cnf file to SIPDefault.cnf.
- Rename the SIPConfigGeneric.cnf file to SIP[MAC_Address].cnf for each phone.
- Reset the phones by unplugging the power cord.
For more information, refer to Converting a Cisco 7940/7960 CallManager Phone to a SIP Phone and the Reverse Process.
Note: This document provides detailed conversion steps and also addresses some common issues that may be encountered during the conversion process
