ROUTING AREA UPDATING IN PACKET RADIO NETWORK

摘要

The invention relates to a cellular packet radio. network and to a method for updating a routing area in a packet radio network. Packet radio support nodes (SGSN) are connected to a digital cellular radio network (BSS), which provides a radio interface for the support nodes for packet-switched data transmission between the support nodes and mobile stations. There is a logical link between a mobile station (MS) and a serving packet radio support node (SGSN). The packet radio network utilizes logical routing areas, each of which comprises one or more cells. Each cell broadcasts information on the routing area to which it belongs. The mobile station sends a routing area update request to the packet radio network when it roams to a new cell which belongs to a different routing area than the old cell. The update request includes the identifiers of the old and new routing area. When the packet radio node detects a routing area update carried out by an unknown mobile station, it sends information on the change of the packet radio node to the mobile station (9, 12). The mobile station then starts a local procedure in the mobile station a network-level procedure (13, 14) with the new support node in order to update the logical link between them for data transmission.