الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
In this Thesis, Security threats affecting Wireless Sensor Networks and mainly clustered based networks are analyzed; the thesis focus on the cryptographic key exchange problem as foundation solution of establishing trust and security in Sensor networks. It is demonstrated that using the latest research & implementations of Elliptic Curve Cryptography that Public Key cryptography is feasible in wireless sensor networks. ECC could assist in securing wireless sensor network by forming a foundation of PKC based system. Two protocols are presented; the first protocol is a key exchange protocol for clustered wireless sensor networks based on ECC, which enables secure key distribution and authentication mechanism. The proposed protocol is optimized for clustered sensor networks and is efficient in terms of complexity, number of message exchange, computation, and storage requirements with optimized security benefits for clustered environment.
The second protocol is introduced which is a new technique to enhance the network and cluster rekeying which happens after new node addition in clustered Wireless Sensor Networks. The concept of node quarantine is introduced, in which the new node is kept in a quarantine state for a specific period of time and is issued a temporary key by the cluster head instead of going all the way through a complete network rekeying each time a new node is added to the cluster. During quarantine, all broadcast communication from or to the new node are encrypted/decrypted by its cluster head using the temp key. The node stays in this quarantine state until the normal (scheduled) periodic network rekeying occurs. This technique reduces the overall network energy consumption when a new node is added, with only a slight compromise in the cluster heads computation load and energy.
Simulation is provided using Matlab with Elliptic Curve Libraries used with permission fromCerticom Corporation.