Method, system and apparatus for causing a communication client to join a media-over-packet communication session

A system comprising:

• a network element connectable to at least one communication client having a particular network identifier via a communication network, said network element comprising a computing apparatus for executing computer-readable instructions stored on a non-transitory computer-readable medium and operable:
• to receive from said at last one communication client a Session Initiation Protocol (SIP) message indicative of an off-hook state of the particular communication client, the particular network identifier of the communication client from which the SIP message is received is one of a plurality of network identifiers registered in association with a particular SIP Uniform Resource Indicator (URI);
• to access a database, said database associating a plurality of SIP URIs with a plurality of network identifiers, including the particular SIP URI and the plurality of associated network identifiers;
• to retrieve from said database a second network identifier associated with a second communication client, the second network identifier being one of the plurality of network identifiers registered in association with the particular SIP URI;
• to determine if there is at least one active communication session in progress with the second network identifier;
• responsive to a positive determination that there does exist at least one active communication session, causing the particular communication client to join the active communication session.

A non-transitory computer-readable medium comprising computer-readable program code which, when executed by a computing apparatus, causes the computing apparatus:

• to receive from said at last one communication client a Session Initiation Protocol (SIP) message indicative of an off-hook state of the particular communication client, the particular network identifier of the communication client from which the SIP message is received is one of a plurality of network identifiers registered in association with a particular SIP Uniform Resource Indicator (URI);
• to access a database, said database associating a plurality of SIP URIs with a plurality of network identifiers, including the particular SIP URI and the plurality of associated network identifiers;
• to retrieve from said database a second network identifier associated with a second communication client, the second network identifier being one of the plurality of network identifiers registered in association with the particular SIP URI,
• to determine if there is at least one active communication session in progress with the second network identifier;
• responsive to a positive determination that there does exist at least one active communication session, causing the particular communication client to join the active communication session.