The present invention relates to a failure detection method and
system operating at the
session control layer, preferably within an IMS / SIP architecture, which monitors the status of an adjacent node with the aid of a
timer mechanism that sets a
heartbeat rate associated with that adjacent node. Monitoring of a communication session takes place by monitoring the liveliness of the nodes handling the session.According to some embodiments, SIP traffic within an on-going communication session is used to determine whether an adjacent node is alive. Failure to receive a SIP message from an adjacent node within a given
heartbeat rate starts a
polling process to decide whether the adjacent node is in a faulty status. In the affirmative, i.e. upon decision that the adjacent node is in a faulty status, the
polling node closes the communication session so that any further billing is prevented.According to some other embodiments, when a transport connection has been established between two adjacent SIP nodes, the node that has initiated the connection starts a
polling process for monitoring the liveliness of the adjacent node. The polling process comprises the step of sending a first polling message requesting the adjacent node to initialise a
timer with a
heartbeat rate proposed by the initiating node or agreed between the two nodes. Initialisation of the
timer triggers in the adjacent node the response to the polling message. Failure to receive an
acknowledgement message from an adjacent node within a given
heartbeat rate determines one or more actions in the initiating node aimed at the decision of a faulty status of the adjacent node. Upon decision that the adjacent node is in a faulty status, the initiating node closes the communication session so that any further billing is prevented.