This volume contains the Proceedings of the 2nd International Workshop on Information Processing in Sensor Networks (IPSN 2003). The workshop was held at the Palo Alto Research Center (PARC), Palo Alto, California, on April 22–23, 2003. Informationprocessinginsensornetworksisaninterdisciplinaryresearcharea with deep connections to signal processing, networking and protocols, databases and information management, as well as distributed algorithms. Because of - vances in MEMS microsensors, wireless networking, and embedded processing, ad hoc networks of sensors are becoming increasingly available for commercial andmilitaryapplicationssuchasenvironmentalmonitoring(e.g.,tra?c,habitat, security), industrial sensing and diagnostics (e.g., factories, appliances), inf- structure maintenance (e.g., power grids, water distribution, waste disposal), and battle?eld awareness (e.g., multitarget tracking). From the engineering and computing point of view, sensor networks have become a rich source of problems in communication protocols, sensor tasking and control, sensor fusion, distributed databases and algorithms, probabilistic reasoning, system/software architecture, design methodologies, and evaluation metrics. This workshop took a systemic approach to address crosslayer issues, from the physical sensor layer to the sensor signal processing and networking levels and then all the way to the applications. Following the successful 1st Workshop on Collaborative Signal and Inf- mation Processing in Sensor Networks at PARC in 2001, this new workshop brought together researchers from academia, industry, and government to p- sent and discuss recent work concerning various aspects of sensor networks such as information organization, querying, routing, and self-organization, with anemphasis on the high-level information processing tasks that these networks are designed to perform.

Table of Contents:
Information Processing in Sensor Networks.- On the Many-to-One Transport Capacity of a Dense Wireless Sensor Network and the Compressibility of Its Data.- Distributed Sampling for Dense Sensor Networks: A “Bit-Conservation Principle”.- Energy-Quality Tradeoffs for Target Tracking in Wireless Sensor Networks.- Adaptive and Decentralized Operator Placement for In-Network Query Processing.- Beyond Average: Toward Sophisticated Sensing with Queries.- Boundary Estimation in Sensor Networks: Theory and Methods.- Scalable Control of Decentralised Sensor Platforms.- Distributed Group Management for Track Initiation and Maintenance in Target Localization Applications.- Using Predictable Observer Mobility for Power Efficient Design of Sensor Networks.- Bounds on Achievable Rates for General Multi-terminal Networks with Practical Constraints.- Source-Channel Communication in Sensor Networks.- On Rate-Constrained Estimation in Unreliable Sensor Networks.- Collaborative Signal Processing for Distributed Classification in Sensor Networks.- Multi-target Sensor Management Using Alpha-Divergence Measures.- A Distributed Algorithm for Managing Multi-target Identities in Wireless Ad-hoc Sensor Networks.- Hypothesis Testing over Factorizations for Data Association.- Energy-Constrained Collaborative Processing for Target Detection, Tracking, and Geolocation.- Array Processing for Target DOA, Localization, and Classification Based on AML and SVM Algorithms in Sensor Networks.- Energy Based Acoustic Source Localization.- A Collaborative Approach to In-Place Sensor Calibration.- On the Error Characteristics of Multihop Node Localization in Ad-Hoc Sensor Networks.- Organizing a Global Coordinate System from Local Information on an Ad Hoc Sensor Network.- A Performance Evaluation ofIntrusion-Tolerant Routing in Wireless Sensor Networks.- Scalable Decentralized Control for Sensor Networks via Distributed Lattices.- Coverage, Exploration, and Deployment by a Mobile Robot and Communication Network.- Distance Based Decision Fusion in a Distributed Wireless Sensor Network.- Maximum Mutual Information Principle for Dynamic Sensor Query Problems.- A Formalism for the Analysis and Design of Time and Path Diversity Schemes in Wireless Sensor Networks.- Sensor Placement for Isotropic Source Localization.- Mobicast: Just-in-Time Multicast for Sensor Networks under Spatiotemporal Constraints.- Sentry-Based Power Management in Wireless Sensor Networks.- Energy Aware Multi-path Routing for Uniform Resource Utilization in Sensor Networks.- Efficient and Fault-Tolerant Feature Extraction in Wireless Sensor Networks.- Event Detection Services Using Data Service Middleware in Distributed Sensor Networks.- Meteorology and Hydrology in Yosemite National Park: A Sensor Network Application.- Detection, Classification, and Collaborative Tracking of Multiple Targets Using Video Sensors.- Decentralised Ground Target Tracking with Heterogeneous Sensing Nodes on Multiple UAVs.- Power-Aware Acoustic Processing.- Distributed Environmental Monitoring Using Random Sensor Networks.- Characterization of Location Error in Wireless Sensor Networks: Analysis and Applications.- A Distributed Algorithm for Waking-up in Heterogeneous Sensor Networks.- Location Tracking in a Wireless Sensor Network by Mobile Agents and Its Data Fusion Strategies.- Acoustic Target Tracking Using Tiny Wireless Sensor Devices.- A Robust Data Delivery Protocol for Large Scale Sensor Networks.