Özet:
This thesis concentrates on establishing a secure group key management scheme in low data rate wireless personal area networks, namely IEEE 802.15.4 standard. In applications where the transmitted data in group communication is sensitive, security of the data should be provided using cryptographic techniques. Security and performance aspects of group key management algorithms are analyzed while initially distributing the group key to all members and redistributing the keys when a member joins or leaves the network. Security of a group key management means that the algorithm should not let the non-group members to have or guess the group key, while performance of the algorithm depends on many factors. First performance attribute is the speed of the algorithm for fast distribution of keys in an efficient way. Then, regarding that the wireless components’ computations cause it to consume power, and this is an unwanted affect, less computational need is important. And finally, suitability to the standard’s needs is another key performance factor. In order to determine the most suitable key management scheme, which offers the best security and performance to IEEE 802.15.4 networks, previously proposed key management algorithms are analyzed and the results are discussed. This analysis shows that the existing algorithms do not fit IEEE 802.15.4’s needs, leading us to propose a new group key management algorithm especially designed for IEEE 802.15.4 networks, namely Hybrid Topology Group Key Management Algorithm (HT-GKMA).