The virtual path (VP) concept has been proposed to simplify traffic control and resource management in future B-ISDN. In particular, call setup processing can be significantly reduced when resources are reserved on VPs. However, this advantage is offset by a decrease in statistical multiplexing gains of the networks. The focus of this paper is on how to improve bandwidth efficiency through adaptive routing when capacity is reserved on all VPs. The authors first examine two VP capacity reservation strategies. They then design and evaluate computationally feasible Markov decision process-based routing algorithms and show that the network blocking probability can be significantly reduced by MDP routing. >

MDP routing in ATM networks using virtual path concept

In this paper, three related virtual channel routing problems on Broadband ISDN are investigated and shown to be NP-complete A distributed routing heuristic is proposed to reduce the call blocking rate while preserving a fast call setup time Various traffic patterns and network topologies are employed to evaluate the performance of the proposed heuristic by simulations Two existing famous routing schemes are also applied for comparison The simulation results show that the proposed heuristic performs better in most cases than the other two schemes

Some routing problems on broadband ISDN

MDP routing for multi-rate loss networks

In the 1990''s, significant advances in fiber optic and switching technology have precipitated the current explosion in the amount of research in future high-speed networks The challenges facing high-speed network researchers result not just from the high data transmission rate but also from other new charactoristics not previously encountered in traditional circuit-switched or packet-switched networks For example, features such as large propagation delay as compared to transmission delay; diverse application demands, constraints on all call processing capacity, and quality-of service QOS support for differant application all present new challenges which arise from the new technology and new applications Thus, much reseach is needed not just to improve existing technologies, but to seek a fundamentally differant approach toward network architectures and protocols In particular, new flow flow control and routing algorithms need to be developed to meet these new challenges The goal of this dissertation is to solve routing problems in the context of high-speed networks taking into account the new network environment In order to better undwerstand the influence of these new network characteristics on the routing problem, we first study the computational delays associated with call admission,routing, and call setup in the future of high-speed networks This study also leads us to explore the similarity between call setup in high-speed networks and circuit-switched networks and to study how approaches toward routing in circuit-switched networks can be adapted for routing in high-speed networks Specifically, based on the Markov Decision Process (MDP) framework, we next design and evaluate state-dependent routing algorithms for high-speed networks which account for the these new network characteristics Finally we consider the Virtual Path (VP) concept that has been proposed to simplify traffic control and resource management in future high-speed networks Thus, in the last part of this dissertation, we also demonstrate the efficiency of MDP-based routing algorithms in virtual path-based networks

Routing in High-Speed Networks

This paper proposes a hierarchical approach to the routing issue in ATM-based broadband multi-service networks. We show how distributed route selection algorithms embedded within network nodes may be managed by a TMN system, by virtue of a management service called load balancing, to increase their adaptivity to network wide conditions and therefore their effectiveness. The paper elaborates on the issues involved, presents specific algorithms and a TMN-compliant management architecture. The proposed management service influences the routing decisions by conveying network-wide information and contributes to the network load balancing by directing the routing algorithms to route traffic to the least congested network areas. Results regarding the effect of the proposed management system on the network operation are also presented.

A Management System for Load Balancing through Adaptive Routing in Multi-Service ATM Networks

Major issues that should be examined in evaluating the performance of networks with dynamic routing are reviewed The characteristics of international 24-h traffic profiles are examined, and proposed dynamic routing schemes are described Gain allocation principles are discussed, and results on circuit savings and fault tolerance of international dynamic routing networks are outlined >

T. Oda

Papers

Dynamic routing schemes for international networks