**Author details**

Gustavo Vejarano *Department of Electrical Engineering and Computer Science, Loyola Marymount University, Los Angeles, CA, USA* 

#### **6. References**

42 Wireless Mesh Networks – Efficient Link Scheduling, Channel Assignment and Network Planning Strategies

density increases.

**5. Conclusion** 

spatial reuse.

**Author details** 

Gustavo Vejarano

MinPower algorithms do. Also, it is confirmed that the technique of only maximizing the spatial reuse by reducing the transmission ranges (i.e., MinPower) does not perform well when the flow density increases (i.e., when the number of flows increases and the number of nodes is kept constant.). On the other hand, the technique of adapting the stability region to the given set of flows by means of TP control (i.e., HSRA) does perform well when the flow

A new framework for the stability analysis of scheduling policies for wireless networks that allow the reservation of future data-subframes has been proposed. The concepts of inputqueue and output-queue were introduced into the framework in order to account for the packets waiting to be scheduled and the schedules assigned to these packets. Based on these concepts, sufficient conditions for the stability of RBDS wireless networks were found.

Within the proposed framework, an RBDS policy which uses the concept of greedy-maximal scheduling was analyzed. The nodes implement this policy by exchanging scheduling packets using the IEEE 802.16 election algorithm. A region in which the proposed reservation-based scheduling policy is stable was found using the framework. It was shown

The HSRA algorithm has been proposed for transmission power control. This algorithm increases the data-packet rates that flows can support and decreases the end-to-end delays. It is based on the adaptation of the stability region of a given link-scheduling policy when only the links that belong to a given set of flows are considered. The algorithm can be readily adapted to any link-scheduling policy whose stability region has been characterized, so it is not limited to any specific scheduling approach such as RTS/CTS-based policies. The improvement on throughput achieved by our algorithm was evaluated by means of. It was shown that it outperforms the classical solution of reducing transmission powers to increase

Future lines of research include the development of a new framework for distributed topology-control algorithms. For example, this framework could based on a game-theoretical approach in which a given set of flows act as players that collaborate to maximize the packet rates they can support while guaranteeing stability. Also, based on the new framework, new distributed topology-control algorithms should be developed for IEEE 802.16 WMNs. Finally, the algorithms should be implemented and tested on WMN testbeds in order to evaluate

the improvement in throughput they achieve in a real scenario.

*Department of Electrical Engineering and Computer Science, Loyola Marymount University, Los Angeles, CA, USA* 

*<sup>o</sup> <sup>Q</sup>* ).

that the size of this region depends on a characteristic of the network topology (i.e., *<sup>j</sup>*

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**Chapter 3** 

© 2012 Chaudhry and Hafez, licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2012 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

**Channel Assignment Using** 

**Topology Control Based on** 

Aizaz U. Chaudhry and Roshdy H.M. Hafez

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/39262

**1. Introduction** 

**1.1. Overview** 

cabling.

**Power Control in Wireless Mesh Networks** 

In this section, an overview of Wireless Mesh Networks (WMNs) is presented, and some unique features which distinguish WMNs from Mobile Ad hoc Networks (MANETs) and Wireless Sensor Networks (WSNs) are listed. The main purpose of this chapter is discussed,

The use of Wireless Local Area Networks (WLANs) has grown tremendously in the past few years due to their ease of deployment and maintenance. However, the access points in these WLANs have to be connected to the backbone network through wired media. Wireless Mesh Networks offer an attractive alternative for providing broadband wireless Internet connectivity by using a wireless backhaul network and eliminating the need for extensive

In traditional WLANs, each Access Point (AP) is connected to the wired network while only a subset of APs is connected to the wired network in WMNs. An AP that is connected to the wired network is called Gateway (GW); APs without wired connections are called Mesh Routers (MRs), and they connect to the GW through multiple hops. Like routers in a wired network, MRs in a WMN forward each other's traffic to establish and maintain their connectivity. MRs and GWs are similar in design, with the only difference that a GW is directly connected to the wired network, while a MR is not. Figure 1 shows a sample mesh network in a typical enterprise such as a university [1]. The following are some unique

and reproduction in any medium, provided the original work is properly cited.

and the contribution is presented along with the main features of this work.

features that distinguish WMNs from MANETs and WSNs [1].

