227793 ⎘
Arrangements for interconnection between switching centres in systems involving main and subordinate switching centres
Virtual PBX based on Feature Server Modules
#2Virtual PBX based on feature server modules
#3Method for selecting impedance setting for loop start trunk line
#4Virtual PBX based on feature server modules
#5Switch proxy for providing emergency stand alone service in remote access systems
#6Method of selecting impedance setting for loop start trunk line