The firmware is typically distributed as a .zip or .cop.sgn file. For a manual installation (common in non-CUCM setups), the files must be unzipped and placed on a . Standard Upgrade Process: SIP configuration on cisco 7975 - FreePBX Community Forums
This version is often cited as the final or most stable SIP firmware for the 7900 series. cmterm-7975-sip.9-4-2sr4