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. Thus,
the signalling switch may be positioned in an information protocol telephony network
environment to initiate, sustain, and terminate connections between a client and
the network or the network and a client, under the control of the resident telephone
routing information protocol software.
