1. Introduction

Distributed sensor networks have received a lot of attention recently due to its wide applications. Especially, as it is expected to provide the basic technique for ubiquitous computing, the development of cost effective and energy-efficient wireless sensor devices is getting more important. Sensor nodes are usually small, low-cost, battery powered, and highly resource constrained. And they can be used to gather a lot of information in various environment after being distributed in great scale. However, they may be deployed in hostile areas where communication is monitored and sensor nodes are subject to capture and manipulation by an adversary. These challenging operational requirements place equally challenging security constraints on distributed sensor network design [6]. Security services such as authentication and key management are critical to secure the communication between sensor nodes in hostile environments. In this paper, we propose cluster-based sensor network architecture and develop pairwise key establishment and authentication mechanisms for secure sensor communication. Theses techniques are based on...