Table of Contents
ISRN Communications and Networking
Volume 2011, Article ID 943504, 8 pages
Research Article

Reliable, Real-Time Routing in Wireless Sensor and Actuator Networks

1Fraunhofer Institute for Communication Systems ESK, 80686 Munich, Germany
2Infineon Technologies, Munich, Germany

Received 26 November 2010; Accepted 3 January 2011

Academic Editors: D. Jayalath and B.-H. Soong

Copyright © 2011 Martin Krogmann et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


We present a novel Reliable, Real-time Routing protocol (3R) based on multipath routing for highly time-constrained Wireless Sensor and Actuator Networks (WSANs). The protocol consists of a newly designed routing metric and a routing algorithm utilizing this metric. Our routing metric enables strong Quality-of-Service (QoS) support based on parallel transmissions which significantly reduces transmission delays in WSANs. A routing algorithm utilizing this metric is presented based on Dijkstra's shortest path. A novel Medium Access Control (MAC) layer that supports dynamical adjustments of retransmission limits, reduces traffic overhead in multipath routing protocols. Thorough simulations have been performed to evaluate the routing protocol, and the results show that real-time performance of WSANs can be vastly improved.