Patent attributes
The present invention discloses a method for preventing hanging resources in connection with an SRNS Relocation Procedure and/or a Routing Area Update Procedure for a terminal roaming in a UMTS or a GPRS network. According to a first aspect of the present invention, when the SGSN from which a terminal is roaming detects a fault after the Relocation Command in the SRNS Relocation Procedure, a Relocation Cancel Procedure also involving any involved GGSN is initiated. According to a second aspect of the present invention, a timer is started in the SGSN to which the terminal is roaming when the Forward Relocation Request in the Routing Area Update Procedure is received. If this SGSN does not receive a Routing Area Update Request within a predefined time period, the SGSN initiate a clean up of the resources that have been occupied during the procedures towards the involved nodes. Finally, according to a third aspect of the present invention, after an uncontrolled shutdown of the terminal, the SGSN cleans up in the resulting hanging resources of the involved nodes when an Identification Request is received in the subsequent attach procedure.
