Patent ID: 7187671

Claim:
A circuit switched Private Branch Exchange System (PABX) comprising switching resources (SW) for providing communications between first subscriber stations (TT) belonging to the circuit switched extension realm of said system, characterized by: a multimedia controller multimedia controller (MMC) adapted to control said switching resources (SW) for providing communications between a first subscriber station (TT) and a second subscriber station (MT) of a Multimedia Data Network (MMN), or between second subscriber stations (MTs), the multimedia controller (MMC) comprising: a) Access Layer means (ALM), containing a plurality of physical and data link sub-layers (PDLSUB) and a Network and transport sub-layers (NTSUB), for connecting the multimedia controller (MMC) with the data network where the second subscribers are connected; b) Protocol Handling Layer means (PHLM), for processing the multimedia protocol messages that are exchanged with a second subscriber related to a communication that involves, at least, a second subscriber; c) Media Handling Layer means (MHL), for handling processes related to media exchange with a second subscriber related to a communication that involves, at least, a second subscriber; d1) Operation and Maintenance Layer means (OML), for setting and storing a data structure related to each admissible second subscriber, said data structure comprising for each admissible second subscriber a directory number belonging to the PABX's number space, and one data or any combination thereof among: network identification and addressing data, multimedia capabilities data, security information data, d2) said Operation and Maintenance Layer means (OML) comprising means for setting (ST 121 –ST 125 ) in a database (DB) the relationship between a multimedia terminal's data structure and said directory number; e1) Application layer means (AL) for controlling the underlying layers Access Layer means (ALM), Protocol Handling Layer means (PHLM) and Media Handling Layer means (MHL), the AL interfacing with control blocks in the PABX (COL), and comprising means for processing basic services (BSM) for supplementary services (SSM), and e2) said Application Layer means (AL) comprising means for receiving a protocol message from one of said first or second subscriber stations in the form of a primitive to interpret said primitive, to perform control of said switching resources (SW).