Vinod Mirchandani

Mobility Management in Wireless Mesh Networks

A viable support of an on-going or a new session for a subscriber on the move requires an effective scheme for Mobility Management. To this end, an array of protocols such as MIPv4, MIPv6, HMIPv6, FMIPv6 have been proposed for the wired Internet. Unfortunately, the wireless connectivity in the wireless mesh networks (WMNs) gives rise to several issues that limits the direct applicability of these mobility management protocols for the wired network. We have contributed to this chapter by identifying and explaining these issues and then giving a critical review of some of the key research proposals made in this area. The literature review also shows that the proposals offer a limited support for mobility management in multiradio wireless mesh networks (MR-WMN). Thus, we have further contributed, by proposing a scheme to carry out a seamless mobility management in WMN as well as MR-WMN. We have taken into account the lessons learnt from the proposals made in the literature. This chapter has been written in a simple way such that students as well as professionals including those who are new to this area should be able to significantly benefit from reading it.

A method and study of topology control based self-organization in Mesh Networks

An algorithm for self-organization that assigns the channels intelligently in multi-radio wireless mesh networks (MR-WMN) is important for the proper operation of MR-WMN. The aim of the self-organization algorithm is to reduce the overall interference and increase the aggregate capacity of the network. This can be possible by addressing the two major challenges that are associated with the self-organization of MR-WMN - scalability and stability. In this paper, we have first proposed a generic self-organization algorithm that addresses these two challenges. The basic approach is that of a distributed, light-weight, co-operative multiagent system that guarantees scalability. Second, we have evaluated the performance of the proposed self-organization algorithm for two sets of initialization schemes. The initialization process results in a topology control of MR-WMN by way of spatial distribution of connectivity between the mesh nodes. The results have been obtained for realistic scenarios of MR-WMN node densities and topologies.

Performance Evaluation of a SLA Negotiation Control Protocol for Grid Networks

A framework for an autonomous negotiation control protocol for service delivery is crucial to enable the support of heterogeneous service level agreements (SLAs) that will exist in distributed environments. We have first given a gist of our augmented service negotiation protocol to support distinct service elements. The augmentations also encompass related composition of the services and negotiation with several service providers simultaneously. All the incorporated augmentations will enable to consolidate the service negotiation operations for telecom networks, which are evolving towards Grid networks. Furthermore, our autonomous negotiation protocol is based on a distributed multi-agent framework to create an open market for Grid services. Second, we have concisely presented key simulation results of our work in progress. The results exhibit the usefulness of our negotiation protocol for realistic scenarios that involves different background traffic loading, message sizes and traffic flow asymmetry between background and negotiation traffics.

Channel Assignment Techniques for 802.11-Based Multiradio Wireless Mesh Networks

This chapter gives an in-depth coverage of the area of channel assignment in 802.11-based multiradio wireless mesh networks (MR-WMN). Multiple channels in a MR-WMN can substantially increase the aggregate capacity of the Wireless Mesh Networks (WMN) if the channels are assigned to the nodes such that the overall interference is limited. To this end, use of graph theory to understand and address this problem facilitated by different representations of MR-WMNs is explained. Further, the inherent properties of the 802.11 radios physical layer are identified to explain their influence on channel interference. We also examine the ways by which the emerging 802.11k standard will help to carry out an effective channel assignment. The usefulness of this chapter is made complete by giving a taxonomy of existing solutions, which is used as a preview to provide an extensive survey of the key research approaches proposed in the literature for channel assignment. We have contributed by way of putting together a comprehensive overview of the work in this area, which we believe does not exist with a similar scope. This chapter has been written such that it can be enjoyed and grasped by students as well as professionals.

A Non-TPC Based Enhanced Topology Control Process for Multi-radio Wireless Mesh Networks

The connectivity of the mesh nodes in a multi-radio wireless mesh network (MR-WMN) defines its topology, which influences the overall system capacity. In contrast to a transmit power control (TPC) based approach for topology control of a WMN considered in the literature, our work in this paper is based on a less complex non-TPC method. A path reduction algorithm forms the underlying strategy of our non-TPC approach and its suitability is explained in details with the support of simulation results. We have then described our enhanced process for topology control that at the core is based on initializing all the mesh nodes in the system concurrently. The enhanced process has been implemented and evaluated with the help of NetLogo tool that facilitates multi-agent based simulation. Simulation results obtained show the effectiveness of the enhanced process in terms of improved interference cost reduction and decrease in path length.

Smart communications network management through a synthesis of distributed intelligence and information

Demands on communications networks to support bundled, interdependent communications services (data, voice, video) are increasing in complexity. Smart network management techniques are required to meet this demand. Such management techniques are envisioned to be based on two main technologies: (i) embedded intelligence; and (ii) up-to-the-millisecond delivery of performance information. This paper explores the idea of delivery of intelligent network management as a synthesis of distributed intelligence and information, obtained through information mining of network performance.

Performance Evaluation of a Self-Organising Scheme for Multi-Radio Wireless Mesh Networks

Multi-radio wireless mesh networks (MR-WMN) can substantially increase the aggregate capacity of the wireless mesh networks (WMN) if the channels are assigned to the nodes in an intelligent way so that the overall interference is limited. We propose a generic self-organisation algorithm that addresses the two key challenges of scalability and stability in a WMN. The basic approach is that of a distributed, light-weight, co-operative multiagent system that guarantees scalability. The usefulness of our algorithm is exhibited by the performance evaluation results that are presented for different MR-WMN node densities and typical topologies. In addition, our work complements the Task Group 802.11s extended service set (ESS) mesh networking project work that is in progress.

The Multiagent System for Channel Selection and Topology Control on 802.11 Based Mesh Networks

To address the problem of topology control on multi-radio wireless mesh networks a distributed, lightweight, co-operative multiagent system that guarantees scalability has been developed and validated by simulation. Our goal is twofold, to select channels so to reduce interference, and improve connectivity by shortening paths between portal and client nodes. As this system is to be deployed over large networks the scalability and stability of the solution are of the main concern. The proposed algorithms have been implemented and evaluated with the Java based framework as well as NetLogo a multiagent simulation tool. The positive attributes of the algorithms are demonstrated through the comprehensive simulation result analysis.

A topology control-based self-organisation in wireless mesh networks

An algorithm for self-organisation that assigns the channels intelligently in multi-radio wireless mesh networks (MR-WMN) is important for the proper operation of MR-WMN. The aim of the self-organisation algorithm is to reduce the overall interference and increase the aggregate capacity of the network. In this paper, we have first proposed a generic self-organisation algorithm that addresses these two challenges. The basic approach is that of a distributed, light-weight, cooperative multiagent system that guarantees scalability. Second, we have evaluated the performance of the proposed self-organisation algorithm for two sets of initialisation schemes. The initialisation process results in a topology control of MR-WMN by way of spatial distribution of connectivity between the mesh nodes. The results have been obtained for realistic scenarios of MR-WMN node densities and topologies. We have shown in addition the need to develop non-transmit power control based algorithms to achieve a further increase in system capacity.

Evaluation of a self-organization scheme with topology control in mesh networks

Mesh networks with an autonomous channel assignment can be used as a viable cost-effective alternative for a last mile broadband access. The channel assignment algorithm in mesh networks should be capable of reducing the overall interference in it. In this paper we have: (i) summarized the usefulness of our algorithm by drawing a comparison between the key features of our self-organization scheme with those of other significant schemes in literature, (ii) proposed a process for initiating the topology of self-organized mesh networks (iii) evaluated the impact of the initialization process on the performance of the self-organization algorithm for realistic scenarios with different mesh node densities and topologies.