Mobile Ad-hoc Networks Of Distributed Security Algorithms Research

Mobile ad hoc networking (MANET) is a new field of wireless communication. The most important application of this technology is in military affairs such as SURAN and LCR. Different from conditional wireless networks, MANET is a new type one whose communications depend on cooperation of mobile network nodes, but not on any fixed installations. Now this technology is also developed for commerce purpose. To provide security support for MANET is challenging due to its unique characteristics. Most study focus on how to establish security strategy based on distributed cryptosystem.This paper first provides a introduction of MANET's development in world, then discusses the distributed cryptography algorithm used to ensure the safety of MANET. Current distributed cryptosystem exposes some shortcomings, which don't fit MANET's demand. One of the shortcomings lying in current secret sharing scheme includes: (1) The threshold k is fixed after we have specified the system parameters. (2) Every participant has uniform power, which isn't consistent with different classes in the society. (3) Any group with at least k participants can compute the secret, which is unfavorable to specify valid group and invalid group. Another shortcoming is that we must refresh the secret S or divide S again when the network members alter, which will increase the difficulty of secret management and the cost of calculation and communication.Our study manages to solve these problems. Firstly, we propose a new secret sharing scheme based on multi-resolution filters. The new scheme has many merits such as the dynamic threshold, Secret shadow holders can be put different powers, system can specify valid groups to reconstruct secret. A group cryptography (signature) scheme is also constituted in the paper. Then, we find a new algorithm to distribute new secret shadows to new group members. Without trusted center, this algorithm only need t (t is the threshold) participants' cooperation and 6t times broadcasting. In the last part of the paper, we demonstrate that the algorithm has high security and is better than shuffling scheme in aspects of reliability and secret management.