A common wireless sensor network architecture
Vlado Handziski, Andreas Köpke, Holger Karl, Adam Wolisz · 2003
Wireless sensor network (WSN) research is currently heavily fragmented: Independent developmentstake place on both sides of the Atlantic, in many different research groups. There is not yet a common“lingua franca” as in some other fields of networking research, where e.g. Linux on Intel processorsor the Network Simulator [1] have achieved such a status—with all the advantages and disadvantages ofsuch a predominance. In WSNs, the need for a harmonization of research efforts is particularly felt in thefollowing areas.Simulation environments Many different research groups use different simulation environmentsfor performance evaluation. Currently popular tools include NS/2, Opnet, GlomoSim, Qualnet, or Om-NET++. None of these simulation tools perfectly meet the demands of WSNs. For example, the wirelesschannel model is too simplistic and not easily changed (NS/2), not all relevant protocols are easily avail-able (Omnet), some are commercial (Opnet, Qualnet), some are too infrequently used to easily allowcomparison of results with work of other researchers (all tools with the possible exception of NS/2).More importantly, there is no simulation tool for which convincing models of applications or sensorexcitation are available.Hardware platforms The overall setup of sensor node prototypes that have been developed and arecurrently used by different groups for experimental research is in principle very similar. Examples forsuch nodes include the Mica Motes, the nodes used by the EYES project [2], and nodes developed locallyat Technische Universitt Karlsruhe, ETH Zrich, Freie Universitt Berlin, or Technische Universitt Dresden.Typical microcontrollers are the Atmel, Motorola microcontrollers or the Texas Instruments MSP 430;usable radio modems include those by RFM, Chipcon, Maxim, Nordic, RFMD, Xemics, Infineon andothers; also, Bluetooth chipsets are sometimes used.While all of these nodes have their individual advantages and disadvantages and the level of diversityis natural for the current state of WSN research, a lot of synergy could be gained if a convergence to asingle prototype could be achieved. The economies of scales alone would make such an effort worthwhileby making prototype nodes available in larger quantities at low cost. The Mica Motes offerings byCrossbow are a step in this direction, but are still somewhat expensive. Possibly, the current developmentsin the IEEE 802.15.4 standardization process will create sufficient pressure towards unification.Moreover, this multitude of prototypes often renders experimental results difficult to compare. Radiomodems have different modes of operations with different power consumptions, resulting in differentlyoptimized lower-layer protocols. While these solutions are important and necessary, what is still missingis the next logical step in comparing the design decisions for example for MAC layer protocols that resultfrom various properties of a specific node.Appeared in Proc. 1. GI/ITG Fachgesprach ``Sensornetze'' (Technical Report TKN-03-012 of the Telecommunications Networks Group, Technische Universitat Berlin), pp. 10-17, Berlin, July 2003