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Abstract
Abstract
A wireless ad hoc network is a collection of autonomous nodes or terminals which communicate with each other by forming a multi-hop radio network and maintaining connectivity in a decentralized manner. The principle behind ad hoc networking is multi-hop relaying, which means that the messages are transmitted by the other nodes if the target node is not directly reachable. The absence of any central coordinator or base stations makes it difficult to manage the network. The network topology in the ad hoc wireless network is highly dynamic due to the mobility of nodes. They may move in and out of the range of each other.
As a result on what mentioned earlier, the secure communication in ad hoc networks is a critical demand and the key management process is one of the most eminent preconditions. However, common authentication schemes are not applicable in ad hoc networks because public key infrastructures with a centralized certification authority are hard to deploy there. Key management is an essential cryptographic primitive upon which other security primitives are built. However, most of the existing key management schemes for wired networks are not suitable for ad hoc networks. They are either too inefficient or not functional on an arbitrary or unknown network topology, or not tolerant to a changing network topology or link failures. So it becomes a must to thought in a robust flexible way to overcome these challenges.
The proposed work merge the clustering method and the threshold key management technique to make distributed authentication architecture that can react with the frequent changing topology of the network.
The recorded experimental results show that the proposed architecture has availability rate achieved about (95.5%) and able to communicate securely in one ninth (1/9) of the time needed for other architectures to attain the same results. Meanwhile, the logon time for the new nodes takes on average about 23.7s only to be authenticated.