Stephen Dawson-Haggerty

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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)
1 Edited portions of this report have appeared or will appear in references [56, 55, 15, 26, 40]. We gratefully acknowledge a number of remote collaborators that contributed to this project before and during the workshop: Abstract We report on investigations, conducted at the 2006 JHU Summer Workshop, of the use of articulatory features in automatic speech(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)
We describe an approach for how to design an essentially more scalable, flexible and resilient electric power infrastructure – one that encourages efficient use, integrates local generation, and manages demand through omnipresent awareness of energy availability and use over time. We are inspired by how the Internet has revolutionized communications(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)
Commercial buildings are attractive targets for introducing innovative cyber-physical control systems, because they are already highly instrumented distributed systems which consume large quantities of energy. However, they are not currently programmable in a meaningful sense because each building is constructed with vertically integrated , closed(More)
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)
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)
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)
IP-based sensor networks provide interoperability, but experience shows that interoperability between different protocol implementations is not a binary property. Instead, subtle differences in implementation choices may affect the performance of the resulting system. We present our experiences with the Contiki and TinyOS implementations of the IPv6 stack(More)