Enabling distributed messaging with wireless sensor nodes using TinySIP

Abstract

Smart sensor nodes have the potential to bridge the gap between the physical and digital world. To realize this potential, we need to integrate a network of sensors within a larger context-aware network, so that we can seamlessly interact with everyday objects embedded with sensor nodes. However, sensor networks currently lack high-level messaging abstractions that support convenient user-level interactions. In this paper, we present TinySIP, which is a messaging library that has been designed with the goal of enabling a client on a traditional network to seamlessly interact with the sensor nodes through diverse communication abstractions and familiar devices. TinySIP leverages the communication abstractions provided by the Session Initiation Protocol (SIP). The clients interact with the sensor nodes by sending SIP messages that provide publish-subscribe, instant messaging, and session-based semantics. A gateway maps the SIP messages to a more energy-efficient TinySIP message format, and forwards them to the sensor nodes, which then parse and react to the incoming TinySIP messages. We present the challenges in adapting SIP for resource constrained nodes and report the performance of our TinySIP implementation on Zigbee motes running TinyOS. © Springer-Verlag Berlin Heidelberg 2007.