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This paper presents and evaluates two principles for wireless routing protocols. The first is datapath validation: data traffic quickly discovers and fixes routing inconsistencies. The second is adaptive beaconing: extending the Trickle algorithm to routing control traffic reduces route repair latency and sends fewer beacons. We evaluate datapath(More)
Network congestion occurs when offered traffic load exceeds available capacity at any point in a network. In wireless sensor networks, congestion causes overall channel quality to degrade and loss rates to rise, leads to buffer drops and increased delays (as in wired networks), and tends to be grossly unfair toward nodes whose data has to traverse a larger(More)
Nodes in sensor networks often encounter spatially-correlated contention , where multiple nodes in the same neighborhood all sense an event they need to transmit information about. Furthermore, in many sensor network applications , it is sufficient if a subset of the nodes that observe the same event report it. We show that traditional carrier-sense(More)
Note This memo documents a part of TinyOS for the TinyOS Community, and requests discussion and suggestions for improvements. Distribution of this memo is unlimited. This memo is in full compliance with TEP 1. Abstract This memo documents the Collection Tree Protocol (CTP), which provides best-effort anycast datagram communication to one of the collection(More)
This paper presents the design, implementation, and experimental evaluation of CMAP (Conflict Maps), a system that increases the number of successful concurrent transmissions in a wireless network, achieving higher aggregate throughput compared to networks that use carrier sense multiple access (CSMA). CMAP correctly identifies and exploits exposed(More)
This paper presents SoftRate, a wireless bit rate adaptation protocol that is responsive to rapidly varying channel conditions. Unlike previous work that uses either frame receptions or signal-to-noise ratio (SNR) estimates to select bit rates, SoftRate uses confidence information calculated by the physical layer and exported to higher layers via the(More)
—Recent research in sensor networks, wireless location systems, and power-saving in ad hoc networks suggests that some applications' wireless traffic be modeled as an event-driven work-load: a workload where many nodes send traffic at the time of an event, not all reports of the event are needed by higher level protocols and applications, and events occur(More)
Carrier sense is a fundamental part of most wireless networking stacks in wireless local area- and sensor networks. As increasing numbers of users and more demanding applications push wireless networks to their capacity limits, the efficacy of the carrier sense mechanism becomes a key factor in determining wireless network capacity.We describe how carrier(More)
We consider the problem of estimating link quality in an ad-hoc wireless mesh. We argue that estimating links well requires combining information from the network, link, and physical layers. We propose narrow, protocol-independent interfaces for the layers, which in total provide four bits of information: 1 from the physical layer, 1 from the link layer,(More)