This paper describes current and proposed protocols for mobility management for public land mobile network (PLMN)-based networks, mobile Internet protocol (IP) wireless asynchronous transfer mode (ATM) and satellite networks. The integration of these networks will be discussed in the context of the next evolutionary step of wireless communication networks. First, a review is provided of location management algorithms for personal communication systems (PCS) implemented over a PLMN network. The latest protocol changes for location registration and handoff are investigated for mobile IP followed by a discussion of proposed protocols for wireless ATM and satellite networks. Finally, an outline of open problems to be addressed by the next generation of wireless network service is discussed.

http://www.cs.tcd.ie/~htewari/papers/ieee99.pdf

Mobility management in next-generation wireless systems

If you want to get Handbook of Internet Computing pdf eBook copy write by good Handbook of Wireless Networks and Mobile Computing Google Books. Mobile Computing General. Handbook of Algorithms for Wireless Networking and Mobile Computing by Azzedine Boukerche (Editor). Call Number: TK 5103.2. CITS4419 Mobile and Wireless Computing software projects related to wireless networks, (2) write technical reports and documentation for complex computer.

Handbook of wireless networks and mobile computing

Satellite networks provide global coverage and support a wide range of services, low Earth orbit (LEO) satellites provide short round-trip delays and are becoming increasingly important. One of the challenges in LEO satellite networks is the development of specialized and efficient routing algorithms. In this work, a datagram routing algorithm for LEO satellite networks is introduced. The algorithm generates minimum propagation delay paths. The performance of the algorithm is evaluated through simulations. The robustness issues of the algorithm are also discussed.

/pdf/a-distributed-routing-algorithm-for-datagram-traffic-in-leo-4lvc9s128c.pdf

A distributed routing algorithm for datagram traffic in LEO satelitte networks

An asynchronous transfer mode (ATM)-based concept for the routing of information in a low Earth orbit/medium Earth orbit (LEO/MEO) satellite system including intersatellite links (ISLs) is proposed. Specific emphasis is laid on the design of an ATM-based routing scheme for the ISL part of the system. The approach is to prepare a virtual topology by means of virtual path connections (VPCs) connecting all pairs of end nodes in the ISL subnetwork for a complete period in advance, similar to implementing a set of (time dependent) routing tables. The search for available end-to-end routes within the ISL network is based on a modified Dijkstra (1959) shortest path algorithm (M-DSPA) capable of coping with the time-variant topology. With respect to the deterministic time variance of the considered ISL topologies, an analysis of optimization aspects for the selection of a path at call setup time is presented. The performance of the path search in combination with a specific optimization procedure is-by means of extensive simulations-evaluated for example LEO and MEO ISL topologies, respectively.

ATM-based routing in LEO/MEO satellite networks with intersatellite links

Today, both the military and commercial sectors are placing an increased emphasis on global communications. This has prompted the development of several low earth orbit satellite systems that promise worldwide connectivity and real-time voice communications. This article provides a tutorial overview of the IRIDIUM low earth orbit satellite system and performance results obtained via simulation. First, it presents an overview of key IRIDIUM design parameters and features. Then, it examines the issues associated with routing in a dynamic network topology, focusing on network management and routing algorithm selection. Finally, it presents the results of the simulation and demonstrates that the IRIDIUM system is a robust system capable of meeting published specifications.

/pdf/an-operational-and-performance-overview-of-the-iridium-low-3z8tz0z3m1.pdf

An operational and performance overview of the IRIDIUM low earth orbit satellite system

We propose a new framework for the link assignment (i.e., topological design) problem that arises from the use of intersatellite links (ISL's) in low-earth orbit (LEO) satellite networks. In the proposed framework, we model an LEO satellite network as a finite state automaton (FSA), where each state corresponds to an equal-length interval in the system period of the LEO satellite network. This FSA-based framework allows the link assignment problem in LEO satellite networks to be treated as a set of link assignment problems in fixed topology networks. Within this framework, we study various link assignment and routing schemes. In particular, both regular link assignment and link assignment optimized by simulated annealing are considered. For each link assignment, both static and dynamic routing schemes are considered. Our simulation results show that the optimized link assignment combined with static routing achieves the best performance in terms of both newly initiated call blocking probability and ongoing call blocking probability. The results also show that when the link assignment is the same, static routing gives better performance than dynamic routing since the latter requires a substantial amount of time to stabilize its routing table after a state transition.

FSA-based link assignment and routing in low-earth orbit satellite networks

We investigate a topological design and routing problem for low Earth orbit (LEO) satellite communication networks where each satellite can have a limited number of direct inter-satellite links (ISLs) to a subset of satellites within its line-of-sight. First, we model LEO satellite network as a FSA (finite state automaton) using satellite constellation information. Second, we solve a combined topological design and routing problem for each configuration corresponding to a state in the FSA. The topological design (or link assignment) problem deals with the selection of ISLs, and the routing problem handles the traffic distribution over the selected links to maximize the number of carried calls. This NP-complete mixed integer optimization problem is solved by a two-step heuristic algorithm that first solves the topological design problem, and then finds the optimal routing. The algorithm is iterated using the simulated annealing technique until the near-optimal solution is found. The link assignment table and the routing table that are pre-calculated off-line for each state are loaded into the satellites and a new set of these tables are retrieved at each state transition. The simulation result shows that the proposed method is applicable to practical LEO satellite networks.

Topological design and routing for low-Earth orbit satellite networks

We compare the performance of two routing schemes for LEO satellite networks through simulation. The two routing schemes represent static and dynamic routing for the case where the LEO satellite network is modeled as a finite state automaton (FSA). Each state in this FSA modeling corresponds to an equal-length interval within the period of the LEO satellite network. Modeling the LEO satellite network in this way allows us to consider the LEO satellite network as if it is a fixed topology network within each state. The routing table for the static routing is fixed within each state whereas that for the dynamic routing is updated continuously according to the shortest-path algorithm. The simulation results show that the static routing performs better in terms of newly initiated call blocking than the dynamic one. The results also show that the static routing gives lower ongoing call blocking probabilities than the dynamic counterpart since the former's pre-computed routing table is less susceptible to the abrupt topological change during a state transition.

Performance comparison of static routing and dynamic routing in low-Earth orbit satellite networks

In many previous low Earth orbit (LEO) satellite networks, intersatellite links (ISLs) are used to enhance the capability of the networks. The ISLs are continuously deleted and established since the visibility between satellites changes over time. These topological changes require rerouting of the traffic on ISLs, which unavoidably involves dropping of some ongoing calls. In general, such an ongoing call dropping degrades the quality-of-service (QoS) more severely than an initiated call blocking. We propose a call admission control scheme that allows a flexible tradeoff between dropped ongoing calls and blocked initiated calls. The call admission control scheme makes use of two techniques: traffic recasting and traffic projection. The traffic recasting maps the current traffic onto the network after the topological change whereas the traffic projection projects the recast traffic from the current time to the time of the topological change. The projected traffic is used to estimate the increase in ongoing call dropping whose QoS penalty is compared against that of increased newly initiated call blacking to make the call admission decision. Simulation results show that the proposed call admission control scheme significantly reduces the ongoing call dropping probability with only a marginal increase in the initiated call blocking and call completion probabilities.

Byoung Wan Kim

Papers

FSA-based link assignment and routing in low-earth orbit satellite networks

Topological design and routing for low-Earth orbit satellite networks

Performance comparison of static routing and dynamic routing in low-Earth orbit satellite networks

A predictive call admission control scheme for low Earth orbit satellite networks