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For nearly a decade, wireless sensor network research and development largely assumed that the Internet architecture was ill suited for sensor network applications. Many in the field argued that Internet protocols were impractical for the resource constrained devices that were being embedded in the physical world; that the end-to-end architecture was(More)
Responding to the increasing interest to connect wireless sensor networks (WSN) to the Internet, the IETF has proposed standards that enable IPv6-based sensor networks. Specifically, the IETF 6LoWPAN and RoLL working groups developed standards for encapsulating IPv6 datagrams in 802.15.4 frames, neighbor discovery , and routing that allow sensor networks to(More)
We present the architecture, design, and preliminary evaluation of ACme, a wireless sensor and actuator network for monitoring AC energy usage and controlling AC devices in a large and diverse building environment. The ACme system consists of three tiers: the ACme node which provides a metering and control interface to a single outlet, a network fabric(More)
Interoperability is essential for the commercial adoption of wireless sensor networks. However, existing sensor network architectures have been developed in isolation and thus interoperability has not been a concern. Recently, IP has been proposed as a solution to the interoperability problem of low-power and lossy networks (LLNs), considering its open and(More)
We present A-MAC, a receiver-initiated link layer for low-power wireless networks that supports several services under a unified architecture, and does so more efficiently and scalably than prior approaches. A-MAC's versatility stems from layering unicast, broadcast, wakeup, pollcast, and discovery above a single, flexible synchronization primitive. A-MAC's(More)
An emerging class of sensor networks focuses on reliable collection of high-resolution signals from across the network. In these applications, the system is capable of acquiring more data than can be delivered to the base station, due to severe limits on radio bandwidth and energy. Moreover, these systems are unable to take advantage of conventional(More)
We report on an experimental case study of personalized lighting controls built on top of an infrastructure designed to enable rapid development of applications in commercial buildings. Our personalized lighting controls (PLC) use an existing standard commercial building lighting automation system and require no new hardware to deploy. PLC presents(More)
As more and more <i>physical information</i> becomes available, a critical problem is enabling the simple and efficient exchange of this data. We present our design for a simple RESTful web service called the Simple Measuring and Actuation Profile (sMAP) which allows instruments and other producers of physical information to directly publish their data. In(More)
We report on investigations, conducted at the 2006 Johns Hopkins Workshop, into the use of articulatory features (AFs) for observation and pronunciation models in speech recognition. In the area of observation modeling, we use the outputs of AF classifiers both directly, in an extension of hybrid HMM/neural network models, and as part of the observation(More)