A Distributed Public Key Caching Scheme in Large Wireless Networks.

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Yuan Kong (Creator)
The University of North Carolina at Greensboro (UNCG )
Web Site: http://library.uncg.edu/
Jing Deng

Abstract: When asymmetric cryptography techniques are used in wireless networks, the public keys of the nodes need to be widely available and signed by a Certificate Authority (CA). However, the existence of a single CA in large wireless networks such as mobile ad hoc networks and wireless sensor networks can lead the hotspot problem and become a security weakness. In this work, we propose a distributed technique to cache the public keys on regular nodes. Due to the limited memory size that each node is allowed to dedicate for key caching, only some keys can be cached. In our proposed technique, each node caches the public keys of a mix of local and remote nodes. The local nodes are defined as the nodes within the same neighborhood according to the transmission range, while the remote nodes are the ones outside the range. Access to the public keys of other nodes is possible based on a chain of trust. Multiple copies of public keys from different chains of trusted nodes provide fault tolerance. We explain our technique in detail and investigate its salient features in this work. An interesting observation is the need to balance caching public keys of local nodes and remote nodes. We studied the optimum local/remote public key caching ratios for different networks via investigating the availability of the number of required public key copies. These simulation results showed that by balancing the caching public keys with the optimum ratios, the availability of the required public keys kept increasing and finally became stable. We also did the simulation about studying the number of hops to find the first copies of required public keys. The results showed how local/remote ratios affected the minimum number of hops for reaching the first copies.

Additional Information

Language: English
Date: 2010
Wireless networks, Cryptography, Certificate authority, Public keys, Caching.
Wireless communication systems.
Telecommunication systems.
Cache memory.

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