Versions prior to 8.5.4 suffered from weak cipher suites. Version 8.5.4 updated the SIP stack to support TLS 1.0 (and partial 1.2 in later sub-builds), allowing secure registration to modern CUCM versions (11.x and 12.x).
Cisco released numerous firmware versions for the 7941/7961 series. So why does the VoIP community still search for cmterm 7941 7961 sip 8 5 4 zipl ? The answer lies in the evolution of SIP compatibility. cmterm 7941 7961 sip 8 5 4 zipl
Before deployment, you must understand the naming convention. Cisco follows a strict schema for its phone firmware bundles. Versions prior to 8