Abstract: A Bridge Call Appearance (BCA) Group including a plurality of peer-to-peer packet-based devices and methods for operating the BCA Group are provided by embodiments of the present invention. In the BCA Group at least one peer-to-peer packet-based device is designated as a primary device and remaining peer-to-peer packet-based devices are designated as secondary devices. An example of such a system is an office environment including a boss's terminal set designated as a primary device and the boss's assistant's terminal sets designated as secondary devices. The secondary devices provide support for the primary device when the primary device is unavailable. The primary network device acts as an intermediary for protocol signaling involving a secondary network device and an other device with which the secondary network device is communicating.

Abstract: A signalling switch for use in information protocol telephony is provided, which can initiate, sustain, and terminate a plurality of discrete voice and data calls simultaneously. A plurality of cards are mounted on a computer bus, where the first card is a single board computer whose function is to act as the operations and maintenance control card for the switch. A non-system card functions as a message transport controller card; and there is at least one further non-system card which functions as a master application controller card. Local bus communication among the non-system cards is provided by a local bus found on the message transport controller card. Telephone routing information protocol software is resident in the switch, and the switch communicates externally via Ethernet interfaces.

Abstract: During call establishment through at least one call server, where at least one calling or called party owns at least one service which is to be invoked each time that a call involving that party is to be established, the following steps are carried out. (a) Any party who owns at least one service which is intended to monitor or control any call involving that party is required to register that service with a call server. (b) Establishing a list of controlling services, and inserting services into the list each time a specific call involving a specific party is being established, by first inserting into the list any service owned by the calling party, and then inserting into the same list any service owned by a called party.

Abstract: Whenever a call is being established, a call loop may occur if a call server detects that the call is being re-routed back to a destination to which it has already been routed. Call loop is precluded by establishing a list of controlling services into which all re-routing services of parties who may be involved in the call are inserted. Each destination address for each call-leg is first treated as if it is a service address, and then as if it is a routable address. If the destination to which the call is being re-routed is the address of the party who modified the address, the call will proceed; otherwise any one of the following steps is followed: Returning a “busy” or “loop detected” message; treating the destination address as a routable address, and attempting to reach the network element associated with that address; offloading the call to another network element which is capable of resolving a call loop, or to the network element at the destination of the calling party.