Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Research Article A Flexible and Efﬁcient Key Distribution Scheme for Renewable Wireless Sensor Networks | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2009 Article ID 240610 9 pages doi 2009 240610 Research Article A Flexible and Efficient Key Distribution Scheme for Renewable Wireless Sensor Networks An-Ni Shen 1 Song Guo 1 and Victor Leung2 1 School of Computer Science and Engineering University ofAizu Fukushima-Ken 965-8580 Japan 2Department of Electrical and Computer Engineering University of British Columbia Vancouver BC Canada V6T1Z4 Correspondence should be addressed to Song Guo sguo@ Received 1 February 2009 Accepted 11 April 2009 Recommended by Yang Xiao Many applications of wireless sensor network require secure data communications especially in a hostile environment. In order to protect the sensitive data and the sensor readings secret keys should be used to encrypt the exchanged messages between communicating nodes. Traditional asymmetric key cryptosystems are infeasible in WSN due to its low capacity at each senor node. In this paper we propose a new key distribution scheme for hierarchical WSNs with renewable network devices. Compared to some of the existing schemes our key establishment methods possess the following features that are particularly beneficial to the resource-constrained large-scale WSNs 1 robustness to the node capture attack 2 flexibility for adding new network devices 3 scalability in terms of storage cost and 4 low communication overhead. Copyright 2009 An-Ni Shen 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. 1. Introduction Wireless sensor networks WSNs have been envisioned to be very useful for a broad spectrum of emerging civil and military applications 1 . However sensor networks are also confronted with many security threats such as node compromise routing disruption and false data injection .