Patent ID: 7996012

Claim:
A method of implementing Tandem-Free Operation between a sending Tandem-Free Operation partner and a receiving Tandem-free partner in a telecommunication network, the method comprising: at call setup, carrying out a Tandem-Free Operation negotiation between said partners to establish Tandem-Free Operation therebetween; at interruption of Tandem-Free Operation in at least one direction, maintaining state information and synchronization of a Tandem-Free Operation state machine of the receiving and/or sending partner in the interrupted direction, for the duration of the interruption; at the end of said interruption, resuming receipt and/or sending of the Tandem-Free Operation frames at said receiving and/or sending Tandem-Free Operation partner, with the same phase as was present prior to the interruption, wherein the interruption to the tandem-free operation connection is instigated by an in-path-equipment; and further comprising, during interruption, sending signaling from the in-path equipment to the receiving Tandem-Free operation partner to indicate to that partner that state information and synchronization of the Tandem-Free Operation state machine in the receiving direction should be maintained.