Each node is required to know the topology of the network within its routing zone only. Thus, nodes are updated about topological changes only witin their routing zones. Thus, in spite of the fact that a network can be quite large, the updates are only locally propagated. Since for radius greater than one, the routing zones heavily overlap, the routing tends to be extremely robust. The routes within the network are specified as a sequence of nodes, separated by approximately the zone radius.
Mobility Management is one of the major functions of a GSM or a UMTS network that allows mobile phones to work. The aim of mobility management is to track where the subscribers are, so that calls, SMS and other mobile phone services can be delivered to them.Overview of Mobility Management The location update procedure allows a mobile device to inform the cellular network, whenever it moves from one location area to the next. Mobiles are responsible for detecting location area codes.
General Packet Radio Service (GPRS) is a Mobile Data Service available to users of Global System for Mobile Communications (GSM) and IS-136 mobile phones. GPRS data transfer is typically charged per megabyte of transferred data, while data communication via traditional circuit switching is billed per minute of connection time, independent of whether the user has actually transferred data or has been in an idle state. GPRS can be used for services such as Wireless Application Protocol (WAP) access, Short Message Service (SMS), Multimedia Messaging Service (MMS), and for Internet communication services such as email and World Wide Web access. Global System for Mobile communications (GSM) is the most popular standard for mobile phones in the world. Its promoter, the GSM Association, estimates that 82% of the global mobile market uses the standard .
Structure of the Assignment
A mobility management method and system for wireless data networks include GPRS and UMTS systems. The wireless data network consists of at least one mobile device and one network apparatus. The cells in a wireless data network are partitioned into several routing areas. In the wireless data network, the mobility management activities for a mobile device are characterized by a mobility management finite state machine exercised in both the mobile device and network apparatus. There are three states in the machine: idle state, standby state and ready state. Both the mobile device and network apparatus employ a ready counter, which counts the number of cells crossed by the mobile device in the packet idle period between two packet transmissions. If the counted number reaches a threshold, the mobility management state switches from the ready state to standby state. A mobility management method for a wireless data network having a plurality of routing areas, each routing area having a plurality of cells, the wireless data network performing mobility management by finite state machines in a mobile device and a network apparatus, the finite state machine having a standby state, a ready state and an idle state, each of the mobile device and the network apparatus having a ready counter, the method determining a