. It is the Session Initiation Protocol (SIP) software image for Release 9.4(2) SR4
is an older model. While this firmware enables SIP, newer features like TLS 1.3 or advanced video codecs are not supported. Installation Difficulty:
SIP (designed for interoperability with call control systems beyond Cisco Unified Communications Manager) File Format: Typically distributed as a CUCM installation Key Technical Details
Why would an administrator deliberately choose or stick with this specific version? The SR4 release brought several refinements over earlier 9.4 builds.
: Designed for use with CUCM 6.0 and later, though it is frequently used in open-source PBX environments. Installation Overview