Location management and fault tolerance issues in mobile networks

Mobile networks has become ubiqutous in todays life. The number of people using this technology is rapidly growing each day. The mobile population is expected to reach the figure of nearly 1 billion in the near future. Several research efforts are being undertaken to address various issues in the design and operation of mobile networks. Some of the active research issues in mobile networking include channel allocation, mobility management, signal processing, fault tolerance, routing protocols and interoperability between different mobile networking protocols. In this dissertation we focus on a couple of these research issues namely mobility management and fault tolerance. Mobility management deals with managing the mobile nodes when they move. The network has to maintain connection to the mobile node inspite of the nodes changing location. We develop fundamental bounds for load balanced location management. We develop novel algorithms for load balanced location management in mobile networks. We later derive fundamental bounds satisfied by any load balanced location management algorithm in the presence of failures in the network. We then present a fast recovery protocol to recover from failures in the network. The salient feature of this protocol being the removal of the use of wireless bandwidth in the recovery process. We conclude the thesis by discussing some of the future issues in the area of mobile networks

A novel approach to emergency management of wireless telecommunication system

The survivability concerns the service continuity when the components of a system are damaged. This concept is especially useful in the emergency management of the system, as often emergencies involve accidents or incident disasters which more or less damage the system. The overall objective of this thesis study is to develop a quantitative management approach to the emergency management of a wireless cellular telecommunication system in light of its service continuity in emergency situations – namely the survivability of the system. A particular wireless cellular telecommunication system, WCDMA, is taken as an example to ground this research.The thesis proposes an ontology-based paradigm for service management such that the management system contains three models: (1) the work domain model, (2) the dynamic model, and (3) the reconfiguration model. A powerful work domain modeling tool called Function-Behavior-Structure (FBS) is employed for developing the work domain model of the WCDMA system. Petri-Net theory, as well as its formalization, is applied to develop the dynamic model of the WCDMA system. A concept in engineering design called the general and specific function concept is applied to develop a new approach to system reconfiguration for the high survivability of the system. These models are implemented along with a user-interface which can be used by emergency management personnel. A demonstration of the effectiveness of this study approach is included.There are a couple of contributions with this thesis study. First, the proposed approach can be added to contemporary telecommunication management systems. Second, the Petri Net model of the WCDMA system is more comprehensive than any dynamic model of the telecommunication systems in literature. Furthermore, this model can be extended to any other telecommunication system. Third, the proposed system reconfiguration approach, based on the general and specific function concept, offers a unique way for the survivability of any service provider system.In conclusion, the ontology-based paradigm for a service system management provides a total solution to service continuity as well as its emergency management. This paradigm makes the complex mathematical modeling of the system transparent to the manager or managerial personnel and provides a feasible scenario of the human-in-the-loop management

Techniques of distributed caching and terminal tracking for mobile computing.

by Chiu-Fai Fong.Thesis (M.Phil.)--Chinese University of Hong Kong, 1997.Includes bibliographical references (leaves 76-81).Abstract --- p.iAcknowledgments --- p.iiiChapter 1 --- Introduction --- p.1Chapter 1.1 --- Distributed Data Caching --- p.2Chapter 1.2 --- Mobile Terminal Tracking --- p.5Chapter 1.3 --- Thesis Overview --- p.10Chapter 2 --- Personal Communication Network --- p.11Chapter 2.1 --- Network Architecture --- p.11Chapter 2.2 --- Resource Limitations --- p.13Chapter 2.3 --- Mobility --- p.14Chapter 3 --- Distributed Data Caching --- p.17Chapter 3.1 --- System Model --- p.18Chapter 3.1.1 --- The Wireless Network Environment --- p.18Chapter 3.1.2 --- Caching Protocol --- p.19Chapter 3.2 --- Caching at Mobile Computers --- p.22Chapter 3.3 --- Broadcasting at the Server --- p.24Chapter 3.3.1 --- Passive Strategy --- p.27Chapter 3.3.2 --- Active Strategy --- p.27Chapter 3.4 --- Performance Analysis --- p.29Chapter 3.4.1 --- Bandwidth Requirements --- p.29Chapter 3.4.2 --- Lower Bound on the Optimal Bandwidth Consumption --- p.30Chapter 3.4.3 --- The Read Response Time --- p.32Chapter 3.5 --- Experiments --- p.35Chapter 3.6 --- Mobility Concerns --- p.42Chapter 4 --- Mobile Terminal Tracking --- p.44Chapter 4.1 --- Movement Model --- p.45Chapter 4.2 --- Optimal Paging --- p.48Chapter 4.3 --- Transient Analysis --- p.52Chapter 4.3.1 --- The Time-Based Protocol --- p.55Chapter 4.3.2 --- Distance-Based Protocol --- p.59Chapter 4.4 --- The Reverse-Guessing Protocol --- p.64Chapter 4.5 --- Experiments --- p.66Chapter 5 --- Conclusions & Future Work --- p.71Chapter 5.1 --- Distributed Data Caching --- p.72Chapter 5.2 --- Mobile Terminal Tracking --- p.73Bibliography --- p.76A Proof of NP-hardness of the Broadcast Set Assignment Problem --- p.8

Journal of Telecommunications and Information Technology, 2012, nr 3

kwartalni

Proceedings of the Third International Mobile Satellite Conference (IMSC 1993)

Satellite-based mobile communications systems provide voice and data communications to users over a vast geographic area. The users may communicate via mobile or hand-held terminals, which may also provide access to terrestrial cellular communications services. While the first and second International Mobile Satellite Conferences (IMSC) mostly concentrated on technical advances, this Third IMSC also focuses on the increasing worldwide commercial activities in Mobile Satellite Services. Because of the large service areas provided by such systems, it is important to consider political and regulatory issues in addition to technical and user requirements issues. Topics covered include: the direct broadcast of audio programming from satellites; spacecraft technology; regulatory and policy considerations; advanced system concepts and analysis; propagation; and user requirements and applications

MOBILITY SUPPORT ARCHITECTURES FOR NEXT-GENERATION WIRELESS NETWORKS

With the convergence of the wireless networks and the Internet and the booming demand for multimedia applications, the next-generation (beyond the third generation, or B3G) wireless systems are expected to be all IP-based and provide real-time and non-real-time mobile services anywhere and anytime. Powerful and efficient mobility support is thus the key enabler to fulfil such an attractive vision by supporting various mobility scenarios. This thesis contributes to this interesting while challenging topic. After a literature review on mobility support architectures and protocols, the thesis starts presenting our contributions with a generic multi-layer mobility support framework, which provides a general approach to meet the challenges of handling comprehensive mobility issues. The cross-layer design methodology is introduced to coordinate the protocol layers for optimised system design. Particularly, a flexible and efficient cross-layer signalling scheme is proposed for interlayer interactions. The proposed generic framework is then narrowed down with several fundamental building blocks identified to be focused on as follows. As widely adopted, we assume that the IP-based access networks are organised into administrative domains, which are inter-connected through a global IP-based wired core network. For a mobile user who roams from one domain to another, macro (inter-domain) mobility management should be in place for global location tracking and effective handoff support for both real-time and non-real-lime applications. Mobile IP (MIP) and the Session Initiation Protocol (SIP) are being adopted as the two dominant standard-based macro-mobility architectures, each of which has mobility entities and messages in its own right. The work explores the joint optimisations and interactions of MIP and SIP when utilising the complementary power of both protocols. Two distinctive integrated MIP-SIP architectures are designed and evaluated, compared with their hybrid alternatives and other approaches. The overall analytical and simulation results shown significant performance improvements in terms of cost-efficiency, among other metrics. Subsequently, for the micro (intra-domain) mobility scenario where a mobile user moves across IP subnets within a domain, a micro mobility management architecture is needed to support fast handoffs and constrain signalling messaging loads incurred by intra-domain movements within the domain. The Hierarchical MIPv6 (HMIPv6) and the Fast Handovers for MIPv6 (FMIPv6) protocols are selected to fulfil the design requirements. The work proposes enhancements to these protocols and combines them in an optimised way. resulting in notably improved performances in contrast to a number of alternative approaches

Locating Objects in a Wide-area System

Steen, M.R. van [Promotor]Tanenbaum, A.S. [Promotor