Extending the lifetime of wireless sensor networks remains the most challenging and demanding requirement that impede large scale deployments. Studies showed that considerable energy saving can be achieved only by putting a node’s radio into full sleep mode, therefore, topology control protocols showed to have the most potential in extending the network lifetime. In this paper we present RAT (R...

Let R be a unital semi-simple commutative complex Banach algebra, and let M(R) denote its maximal ideal space, equipped with the Gelfand topology. Sufficient topological conditions are given on M(R) for R to be a projective free ring, that is, a ring in which every finitely generated projective R-module is free. Several examples are included, notably the Hardy algebra H∞(X) of bounded holomorph...

Hosts in wireless networks are usually powered by batteries, thus the lifetime of a network depends on the battery life of each individual host. One major solution to improve energy-efficiency is to minimize the total energy consumption. However, battery energy is a local resource, to save energy at each host and balance the energy consumption among all the hosts in the network appear to be mor...

This paper introduces I-MAC, a new medium access control protocol for wireless sensor networks. I-MAC targets at improving both channel utilization and energy efficiency while taking into account traffic load for each sensor node according to its role in the network. I-MAC reaches its objectives through prioritized and adaptive access to the channel. I-MAC performances obtained through simulati...

This paper introduces a new backoff mechanism for IEEE802.11 which aims to achieve fair channel access without knowledge of the network topology. By adjusting a time interval and the contention window dynamically, the algorithm aims to approach the optimal equilibrium where the time interval is the minimum possible such that every node that faces the same contention successfully sends only one ...

This study investigates the potential of using transmission power control in wireless packet networks with differing number of hops between source and destination. Here we exploit the benefits of power control in the context of multi-hop wireless ad hoc type networks with a distributed media access control. For our investigations we choose several general ad hoc network topologies and studied t...

Ad hoc network is a popular research topic in wireless network recently. It has good performance on the robustness and dynamics, such as minimal configuration and quick deployment for emergency situations. However, the ad hoc network also suffers from the limited power source provision because of its fundamental architecture. Therefore, the power issue becomes one of the most important concerns...

The topology control strategies of wireless sensor networks are very important to reduce the energy consumptions of sensor nodes and prolong the life-span of networks. In this paper, we put forward a minimum-energy path-preserving topology control (MPTC) algorithm. MPTC not only resolves the problem of exceeding energy consumption because of the unclosed region in SMECN[2], but also preserves a...

Congestion control is a key problem in mobile ad-hoc networks. The standard TCP congestion control mechanism is not able to handle the special properties of a shared wireless multihop channel well. In particular the frequent changes of the network topology and the shared nature of the wireless channel pose significant challenges. Many approaches have been proposed to overcome these difficulties...