Apparatus and method for providing existing telephone switching equipment with integrated services digital network capability

摘要

The invention relates to upgrading existing telephone central offices which utilize electromechanical or electronic switching equipment to include the capability of processing calls in the ISDN protocol. In particular, it relates to providing said switching equipment with the capability of controlling the connection, management, and disconnection of telephone circuits using Integrated Services Digital Network (ISDN), a national and international standard set of protocols for providing such circuit control and providing and receiving information via the ISDN protocol for enabling enhanced service in the switching equipment.