More and more wireless networks are deployed with overlapping coverage. Especially in the unlicensed bands, we see an increasing density of heterogeneous solutions, with very diverse technologies and application requirements. As a consequence, interference from heterogeneous sources-also called cross-technology interference-is a major problem causing an increase of packet error rate (PER) and decrease of quality of service (QoS), possibly leading to application failure. This issue is apparent, for example, when an IEEE 802.15.4 wireless sensor network coexists with an IEEE 802.11 wireless LAN, which is the focus of this work. One way to alleviate cross-technology interference is to avoid it in the frequency domain by selecting different channels. Different multichannel protocols suitable for frequency-domain interference avoidance have already been proposed in the literature. However, most of these protocols have only been investigated from the perspective of intratechnology interference. Within this work, we create an objective comparison of different candidate channel selection mechanisms based on a new multichannel protocol taxonomy using measurements in a real-life testbed. We assess different metrics for the most suitable mechanism using the same set of measurements as in the comparison study. Finally, we verify the operation of the best channel selection metric in a proof-of-concept implementation running on the testbed.

Autonomic networking and cooperative communications paradigms have emerged as promising technologies that can pave the way for next generation networks. CONSERN project is focusing on cooperation and collaboration enablers, cooperative decision and control algorithms that will maximise the expected gains by utilising cooperative problem solving for improving energy efficiency in wireless networks. In this paper, cooperative and/or autonomous solutions are captured and a mapping to the envisaged technologies is made. Based on this mapping an initial analysis of the requirements for energy-efficient cooperation is presented. The cooperation deals with information exchange, actions coordination and decision making within and between different types of network nodes. Based on the requirements analysis a set of key cooperation enablers are identified and further elaborated upon.

Considers virtual circuit packet switching communication networks that employ processor sharing type service disciplines and studies their stability when the offered traffic to the network has exponentially bounded burstiness (EBB). The authors employ an exponential characterization (EBB) introduced in a previous work to analyze this type of system in a stochastic setting. They first examine the GPS and PGPS servers in isolation, and demonstrate their superiority to a general server in the stochastic environment. They then show that a network of servers, that are all either GPS or PGPS, is stable whenever the service rate of each node is larger than the total arrival rate to it. In addition, they provide exponential upper bounds to the traffic flows within the network links, and to the backlogs of each session in the various nodes on its path.>

A way to calculate the performance of packet switching communication networks under a fixed (session-based) routing strategy, based on properly bounding the probability distribution functions of the system input processes, is proposed. The bounds suggested, which are decaying exponentials, posses three convenient properties. When the inputs to an isolated network element are all bounded, they result in bounded outputs and ensure that the delays and queues in this element have exponentially decaying distribution. In some network settings, the bounded inputs result in bounded outputs. Finally, natural traffic processes can be shown to satisfy such bounds. These properties enable the calculation of upper bounds for all the interesting parameters of network performance, in a variety of settings.>

A method for evaluating the performance of packet switching communication networks under a fixed, session-based, routing strategy is proposed. The approach is based on properly bounding the probability distribution functions of the system input processes. The suggested bounds which are decaying exponentials, possess three convenient properties. When the inputs to an isolated network element are all bounded, they result in bounded outputs and assure that the delays and queues in this element have exponentially decaying distributions. In some network settings, bounded inputs result in bounded outputs. Natural traffic processes can be shown to satisfy such bounds. Consequently, this method enables the analysis of various previously intractable setups. Sufficient conditions are provided for the stability of such networks, and derive upper bounds for the parameters of network performance are derived.>