Nicos Gollan

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Network Calculus has been proposed and customized as a framework for worst-case analysis in wireless sensor networks (WSNs). It has been demonstrated that this so-called Sensor Network Calculus (SNC) is an effective network dimensioning tool as it allows us to calculate maximum message transfer delays and communication related energy consumption patterns(More)
Non-FIFO processing of flows by network nodes is not a rare phenomenon. Unfortunately, the state-of-the-art analytical tool for the computation of performance bounds in packet-switched networks, network calculus, cannot deal well with non-FIFO systems. The problem lies in its conventional service curve definitions. Either the definition is too strict to(More)
Computing tight performance bounds in feed-forward networks under general assumptions about arrival and server models has turned out to be a challenging problem. Recently it was even shown to be NP-hard [1]. We now address this problem in a heuristic fashion, building on a procedure for computing provably tight bounds under simple traffic and server models.(More)
—Many wireless sensor networks (WSNs) are used to collect and aggregate data from potentially hostile environments. Catering to this, early application scenarios did not put tight constraints on performance properties like delay, but rather focused on ruggedness and energy conservation. Yet, there is a growing number of sceanarios like e.g. production(More)
—Networked sensors and actuators for purposes from production monitoring and control to home automation are in increasing demand. Until recently, the main focus laid on wired systems, although their deployment requires careful planning and expensive infrastructure that may be difficult to install or modify. Hence, solutions based on wireless sensor networks(More)
Network calculus [1, 2] was developed for use in IP and ATM networks. It aims to be a system theory for deterministic queuing, allowing to derive deterministic guarantees on throughput and delay, as well as find bounds on buffer sizes and thereby allow for loss-free transfer. Traditional queuing theory analyzes the average or equilibrium behavior of a(More)
Many wireless sensor networks (WSNs) are used to collect and aggregate data from potentially hostile environments. Catering to this, early application scenarios did not put tight constraints on performance properties like delay, but rather focused on ruggedness and energy conservation. Yet, there is a growing number of scenarios like e.g. production(More)