The objective of a sensor network is the execution of specific signal processing functions on data that are collected in a distributed fashion. The transmission of the data is facilitated by protocols whose operations may be constrained by physical limitations of the network units, while their performance must simultaneously comply with the performance requirements of the deployed signal processing operations. At the same time, the network architecture affects the performance of both the signal processing and the data transmission operations, while some of the sensors may generate high-priority data. In this paper, we consider clustered sensor network topologies deploying a specific stable random access transmission algorithm per cluster, which facilitates high-priority data. We then introduce a dynamic architectural reconfiguration algorithm which controls individual cluster rates for optimal overall network performance. The latter algorithm is facilitated by a high-level traffic rate monitoring protocol. 1. Introduction Wireless sensor networks satisfy signal processing objectives; their performance metrics are thus determined by those of the latter objectives [1]. When time constraints are imposed on high-accuracy signal processing operations, the consequence is increased required overall data rates. At the same time, in wireless sensor networks, observation data are transmitted via appropriate multiple access protocols [2–5], whose performance is a function of the their input data rates, and are collected and processed by life-limited nodes, whose life span is a function of the data rates they process, [6–9]. Thus, required overall data rates, in conjunction with rate-dependent transmission protocol performance and node life spans, necessitate network-architecture and network-operations adaptations, so that the nodes’ survivability limitations do not interfere with the required network overall performance [10, 11]. Since the network-architecture and network-operations adaptations are functions of the acting data rates, it is eminent that data rates be monitored and that rate changes be detected accurately and rapidly [12]. The distinguishing feature in wireless sensor networks is limited life spans of the nodes, induced by energy consumption. Interesting results focusing on energy consumption have been obtained by several researchers: Bounds on energy conservation techniques have been derived in [13], role assignments targeting energy conservation have been developed in [10], energy conservation routing techniques have been proposed in [7, 8, 14],
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