Location Management is defined as the process of tracking the position of a mobile terminal when it moves to its associated area within the network. This allows the network to detect the mobile user’s path for the purpose of call delivery. The location management schema in a public-LAN mobile network (IS-41 and GSM) is based on centralized two-tier database architecture. The root level is called the Home Location Register (HLR) and the second level is called the Visitor Location Register (VLR). The HLR permanently stores all the mobile users’ location information and the types of services subscribed in the user’s profile database. The VLR stores the location information whenever a user registered in the HLR moves to its related location area within the network. By contacting the HLR, the VLR authenticates and updates the mobile user’s current position when a mobile terminal moves from one location area to another. The HLR then updates the mobile terminal’s new location information and removes the mobile terminal from its previous VLR. There can be multiple VLR’s under each HLR in a network. In the current location management schema, all the information requests, queries, acknowledgements have to go through the HLR. This results in excessive overload at the HLR. This overload becomes high when the number of mobile terminals increases within the network. The heavy traffic at the root (HLR) may cause congestion, degradation of the bandwidth at the root and hence becomes a major bottleneck for the entire network. To solve this congestion/bottleneck problem, a modified iterative protocol with VLR cache was introduced, where the VLRs in the network handle all de-registration, registration and acknowledgement of messages. The HLR only handles updating the location information of the mobile terminal in its database. This reduced the excess load/traffic experienced at the HLR thus improving the network’s performance. The modified protocol was tested with different cache replacement policies such as First-In First-Out (FIFO), Random and Least Frequently Visited (LFV) with uniform traffic with random mobile terminal movement. In this thesis report, we extend the previous work in the modified iterative protocol by 1) increasing the topography of the network, to analyze the impact of network’s size on performance and 2) changing the mobile terminal traffic pattern from uniform traffic with random mobile terminal movement to non-uniform traffic with unbalanced probability movement. With these changes, we analyzed the modified protocol’s performance with different cache replacement policies (FIFO, LFV and Random) under uniform traffic with random movement and non-uniform traffic with unbalanced probability movement.

Mobile wireless environments present new challenges to the design and validation of system supports for facilitating development of mobile applications. This dissertation concerns two major system-support mechanisms in mobile wireless networks, namely, location management and service management. We address this research issue by considering three topics: location management, service management, and integrated location and service management. A location management scheme must effectively and efficiently handle both user location-update and location-search operations. We first quantitatively analyze a class of location management algorithms and identify conditions under which one algorithm may perform better than others. From insight gained from the quantitative analysis, we design and analyze a hybrid replication with forwarding algorithm that outperforms individual algorithms and show that such a hybrid algorithm can be uniformly applied to mobile users with distinct call and mobility characteristics to simplify the system design without sacrificing performance. For service management, we explore the notion of location-aware personal proxies that cooperate with the underlying location management system with the goal to minimize the network communication cost caused by service management operations. We show that for cellular wireless networks that provide packet services, when given a set of model parameters characterizing the network and workload conditions, there exists an optimal proxy service area size such that the overall network communication cost for service operations is minimized. These proxy-based mobile service management schemes are shown to outperform non-proxy-based schemes over a wide range of identified conditions. We investigate a class of integrated location and service management schemes by which service proxies are tightly integrated with location databases to further reduce the overall network signaling and communication cost. We show analytically and by simulation that when given a user's mobility and service characteristics, there exists an optimal integrated location and service management scheme that would minimize the overall network communication cost for servicing location and service operations. We demonstrate that the best integrated location and service scheme identified always performs better than the best decoupled scheme that considers location and service managements separately. / Ph. D.

Next generation wireless systems have an IP-based infrastructure with the support of heterogeneous access technologies. One research challenge for next generation all-IP based wireless systems is to design intelligent mobility management techniques that take advantage of IP-based technologies to achieve global roaming between various access networks. To support global roaming, next generation wireless systems require the integration and interoperation of heterogeneous mobility management techniques. Mobility in a hierarchical structure or multilayered environment should be supported. The objective of this study is to develop new mobility management techniques for global roaming support in next generation all-IP based wireless systems. More specifically, new schemes for location management and paging in Mobile IP for network layer mobility support, and new schemes for location management and handoff management in heterogeneous overlay networks for link layer mobility support are proposed and evaluated. For network layer mobility support, a distributed and dynamic regional location management mechanism for Mobile IP is proposed. Under the proposed scheme, the signaling burden is evenly distributed and the regional network boundary is dynamically adjusted according to the up-to-date mobility and traffic load for each terminal. Next, a user independent paging scheme based on last-known location and mobility rate information for Mobile IP is proposed. The proposed scheme takes the aggregated behavior of all mobile users as the basis for paging. For link layer mobility support, an IP-based system architecture for the integration of heterogeneous mobility management techniques is proposed. Three location management schemes under this IP-based architecture are proposed. All the three schemes support user preference call delivery which is a very important feature of next generation wireless communications. A threshold-based enhancement method is also proposed to further improve the system performance. Finally, a hybrid resource allocation scheme for handoff management in wireless overlay networks is proposed. Under this scheme, the overall system resources can be optimally allocated when mobile users are covered by multiple overlay networks.

Network management plays a vital role to keep a network and its application work e ciently. The network management in MANETs is a crucial and the challenging task, as these networks are characterized by dynamic environment and the scarcity of resources. There are various existing approaches for network management in MANETs. The Ad hoc Network Management Protocol (ANMP) has been one of the rst e orts and introduced an SNMP-based solution for MANETs. An alternative SNMP-based solu-tion is proposed by GUERRILLA Management Architecture (GMA). Due to self-organizing characteristic feature of MANETs, the management task has to be distributed. Policy-based network management relatively o ers this feature, by executing and applying policies pre-viously de ned by network manager. Otherwise, the complexity of realization and control becomes di cult Most of the works address the current status of the MANET to take the network man-agement decisions. Currently, MANETs addresses the dynamic and intelligent decisions by considering the present situation and all related history information of nodes into consid-eration. In this connection we have proposed a network management system using agents (NMSA) for MANETs, resolving major issues like, node monitoring, location management, resource management and QoS management. Solutions to these issues are discussed as inde-pendent protocols, and are nally combined into a single network management system, i.e., NMSA. Agents are autonomous, problem-solving computational entities capable of performing e ective operation in dynamic environments. Agents have cooperation, intelligence, and mobility characteristics as advantages. The agent platforms provide the di erent services to agents, like execution, mobility, communication, security, tracking, persistence and directory etc. The platform execution environment allows the agents to run, and mobility service allows them to travel among the di erent execution environments. The entire management task will be delegated to agents, which then executes the management logic in a distributed and autonomous fashion. In our work we used the static and mobile agents to nd some solutions to the management issues in a MANET. We have proposed a node monitoring protocol for MANETs, which uses both static agent (SA) and mobile agents (MA), to monitor the nodes status in the network. It monitors the gradational energy loss, bu er, bandwidth, and the mobility of nodes running with low to high load of mobile applications. Protocol assumes the MANET is divided into zones and sectors. The functioning of the protocol is divided into two segments, The NMP main segment, which runs at the chosen resource rich node (RRN) at the center of a MANET, makes use of SA which resides at same RRN, and the NMP subsegment which runs in the migrated MAs at the other nodes. Initially SA creates MAs and dispatches one MA to each zone, in order to monitor health conditions and mobility of nodes of the network. MAs carrying NMP subsegment migrates into the sector of a respective zone, and monitors the resources such as bandwidth, bu er, energy level and mobility of nodes. After collecting the nodes information and before moving to next sector they transfer collected information to SA respectively. SA in turn coordinates with other modules to analyze the nodes status information. We have validated the protocol by performing the conformance testing of the proposed node monitoring protocol (NMP) for MANETs. We used SDL to obtain MSCs, that repre-sents the scenario descriptions by sequence diagrams, which in turn generate test cases and test sequences. Then TTCN-3 is used to execute the test cases with respect to generated test sequences to know the conformance of protocol against the given speci cation. We have proposed a location management protocol for locating the nodes of a MANET, to maintain uninterrupted high-quality service for distributed applications by intelligently anticipating the change of location of its nodes by chosen neighborhood nodes. The LMP main segment of the protocol, which runs at the chosen RRN located at the center of a MANET, uses SA to coordinate with other modules and MA to predict the nodes with abrupt movement, and does the replacement with the chosen nodes nearby which have less mobility. We have proposed a resource management protocol for MANETs, The protocol makes use of SA and MA for fair allocation of resources among the nodes of a MANET. The RMP main segment of the protocol, which runs at the chosen RRN located at the center of a MANET, uses SA to coordinate with other modules and MA to allocate the resources among the nodes running di erent applications based on priority. The protocol does the distribution and parallelism of message propagation (mobile agent with information) in an e cient way in order to minimize the number of message passing with reduction in usage of network resources and improving the scalability of the network. We have proposed a QoS management protocol for MANETs, The QMP main segment of the protocol, which runs at the chosen RRN located at the center of a MANET, uses SA to coordinate with other modules and MA to allocate the resources among the nodes running di erent applications based on priority over QoS. Later, to reallocate the resources among the priority applications based on negotiation and renegotiation for varying QoS requirements. The performance testing of the protocol is carried out using TTCN-3. The generated test cases for the de ned QoS requirements are executed with TTCN-3, for testing of the associated QoS parameters, which leads to performance testing of proposed QoS management protocol for MANETs. We have combined the developed independent protocols for node monitoring, location management, resource management, and QoS management, into one single network management system called Network Management System using Agents (NMSA) for MANETs and tested in di erent environments. We have implemented NMSA on Java Agent development environment (JADE) Platform. Our developed network management system is a distributed system. It is basically divided into two parts, the Network Management Main Segment and other is Network Management Subsegment. A resource rich node (RRN) which is chosen at the center of a MANET where the Main segment of NMSA is located, and it controls the management activities. The other mobile nodes in the network will run MA which has the subsegments of NMSA. The network management system, i.e., the developed NMSA, has Network manage-ment main (NMSA main), Zones and sector segregation scheme, NMP, LMP, RMP, QMP main segments at the RRN along with SA deployed. The migrated MA at mobile node has subsegments of NMP, LMP, RMP, and QMP respectively. NMSA uses two databases, namely, Zones and sectors database and Node history database. Implementation of the proposed work is carried out in a con ned environment with, JDK and JADE installed on network nodes. The launched platform will have AMS and DF automatically generated along with MTP for exchange of message over the channel. Since only one JVM, which is installed, will executes on many hosts in order to provide the containers for agents on those hosts. It is the environment which o ered, for execution of agents. Many agents can be executed in parallel. The main container, is the one which has AMS and DF, and RMI registry are part of JADE environment which o ers complete run time environment for execution of agents. The distribution of the platform on many containers of nodes is shown in Fig. 1. The NMSA is based on Linux platform which provides distributed environment, and the container of JADE could run on various platforms. JAVA is the language used for code development. A middle layer, i.e., JDBC (java database connection) with SQL provides connectivity to the database and the application. The results of experiments suggest that the proposed protocols are e ective and will bring, dynamism and adaptiveness to the applied system and also reduction in terms network overhead (less bandwidth consumption) and response time.