Recent work in wireless embedded networked systems has followed heterogeneous designs, incorporating a mixture of elements from extremely constrained 8- or 16-bit “Motes ” to less resourceconstrained 32-bit embedded “Microservers.” Emstar is a software environment for developing and deploying

generation. For comparison, we show our new ECC implementation on TelosB motes with a signature time 1.60s and a verification time 3.30s. We also explain the reasons that TelosB mote can not perform better than MICAz even though it is equipped with a 16-bit CPU. We believe that the experiment results

. For comparison, we show our new ECC implementation on TelosB motes with a signature time 1.55s and a verification time 2.25s. We also explain the reasons that TelosB mote can not perform better than MICAz even though it is equipped with a 16-bit CPU. We believe that the experiment results are encouraging

, establishing a pairwise key of 80 bits between any two 8-bit, 7.37-MHz MICA2 motes only requires about 0.13 second of CPU time, 0.33 KB RAM space, and 15 KB ROM space per node.

, different types of measure-ments. Unfortunately, the term sensor is overloaded. Sometimes it is used to refer to the entire piece of hardware consisting of • a microprocessor or CPU (typically 8, 16, or 32 bits) • some amount of non-volatile memory (4KB–2MB) • some amount of random-access-memory (10KB–32MB

developed around it. The pure C OpenWSN stack was ported to four off-the-shelf platforms representative of hardware currently used, from older 16-bit micro-controller to state-of-the-art 32-bit Cortex-M architectures. The tools developed around the low-power mesh networks include visualization and debugging

amplification, 16-bit Analog to Digital Conversion (ADC) and up to 512-tap FIR programmable filtering, which practically meet sensing requirements of very weak signals from real world structures. In this demo, we will first show our sensing module and present its technical design principles. We will then show

, sending few beacons in stable topologies yet quickly adapting to changes. Finally, Magnet addresses transient loops by using data traffic as active topology probes, quickly discovering and fixing routing failures. Magnet runs on six different mote platforms and we have tested it on four testbeds. In most

Copyright © 2012 Muhammad Hamad Alizai et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. We address the challenge of link estimation and routing over highly dynamic links, thats is, bursty links that rapidly shift between reliable and unreliable periods of transmissions. Based on significant empirical evidence of over 100,000 transmissions over each link in 802.15.4 and 802.11 testbeds, we propose two metrics, expected future transmissions (EFT) and MAC3, for runtime estimation of bursty wireless links.We introduce a bursty link estimator (BLE) that based on these twometrics, accurately estimates bursty links in the network rendering them available for data transmissions. Finally, we present bursty routing extensions (BRE): an adaptive routing strategy that uses BLE for forwarding packets over bursty links if they offer better routing progress than long-term stable links. Our evaluation, comprising experimental data from widely used IEEE 802.15.4-based testbeds, reveals an average of 19 % and a maximum of 42 % reduction in the number of transmissions when routing over long-range bursty links typically ignored by routing protocols. Additionally, we show that both BLE and BRE are not tied to any specific routing protocol and integrate seamlessly with existing routing protocols and link estimators. 1.

This paper presents and evaluates two principles for designing robust, reliable, and efficient collection protocols. These principles allow a protocol to benefit from accurate and agile link estimators by handling the dynamism such estimators introduce to routing tables. The first is datapath validation: a protocol can use data traffic as active topology probes, quickly discovering and fixing routing loops. The second is adaptive beaconing: by extending the Trickle code propagation algorithm to routing control traffic, a protocol sends fewer beacons while simultaneously reducing its route repair latency. We study these mechanisms in an implementation called Collection Tree Protocol (CTP) and evaluate their contributions to its performance. We evaluate CTP on 12 different testbeds ranging in size from 20–310 nodes and comprising 7 hardware platforms, on 6 different link layers, and on interference-free and interference-prone channels. In all cases, CTP delivers> 90 % of packets. Many experiments achieve 99.9%. Compared to standard beaconing, CTP sends 73 % fewer beacons while reducing topology repair latency by 99.8%. Finally, when using low-power link layers, CTP has duty cycles of 3 % while supporting aggregate loads of 30 packets/minute. 1