Research On Key Techniques Of Secure Multicast In Mobile Ad Hoc Networks

With more and more mobile ad hoc networks being applied to the multi-party communication and multi-node cooperative environments such as conference, academic, disaster relief and battlefields in recent years, multicast is a very hot area of mobile ad hoc networks and attracts attentions of many researchers. Meanwhile, mobile ad hoc networks are more vulnerable to attacks than stationary network due to its intrinsic properties such as the dynamic topology, node resource constraints and not any fixed infrastructure. Since the traditional network security facilities are not suitable to MANET, the security problem becomes the decisive factor for practical application of multicast techniques in MANET.The research works presented in this dissertation mainly focus on key techniques of secure multicast in mobile ad hoc networks.First of all, this dissertation extensively studies existent group key management schemes in mobile ad hoc networks and a secure group key agreement protocol based on threshold secret sharing (TNSGKAP) is proposed in order to overcome the drawback of existent schemes. TNSGKAP does not require a trusted dealer and only runs an interactive protocol to generate group sharing secret key among n parties. The protocol can adapt to topological change automatically and increase the security of the protocol. The applications of ECC and bilinear pairing improve the performance of group key generation algorithm and the verifications of the shares of sub-secret and group secret further enhance the security of the protocol. In the scheme, group rekeying and group key consistency management algorithms based on group key service center (GKSC) are also proposed, which can effectively reduce communication and computation overheads of the protocol and avoid the occurrence of isolated nodes caused by the group key inconsistency.Secondly, a secure and efficient group key management scheme (SEGKM) is proposed. SEGKM is based on the cluster-based CQn model (CCQn) that effectively reduces communication overhead and improves the flexibility, scalability and fault-tolerance of the protocol. Efficient signcryption and threshold signature schemes are also proposed and the verifications of the shares of sub-secret and group secret based on this scheme eliminate the security shortcomings of A-GDH and TGDH and enhance the security of the protocol. SEGKM uses the secret distribution center to generate group sharing secret key among n parties and further increases the performance and security of the scheme.Thirdly, in order to overcome the drawback of the existent multicast source authentication protocol in wireless sensor networks (WSN), the PKC-based services for WSN are explored and an efficient ID-based multicast authentication protocol is presented. The protocol with message recovery provides the feature that the message is recoverable from the signature and hence the communication and computation overheads of the protocol have been reduced greatly. The performance analysis results show that the proposed scheme can effectively reduce resource cost, adapt the characteristics of WSN and is clearly superior to the HESS, Zhang and BLS protocols.Fourthly, great challenges to designing the secure multicast routing protocol based on QoS have been brought because of the characteristics of MANET such as node resources constraints. In this dissertation, the characteristics of wireless network traffic are analyzed and a link prediction model based on self-similarity and a secure QoS-based multicast routing protocol (SQMRP) are respectively put forward. A core election algorithm in SQMRP is presented and used to generate a crossed cube-connected core network. The core network is the core of all multicast groups and connects each multicast group member using SPT. Therefore, the performance of SQMRP has been improved, which can adapt to the characteristics of MANET such as the dynamic topology. SQMRP estimates Hurst parameters by wavelet analysis, measures network traffic by Hurst parameters and solves measurement problems of multi-constraint QoS routing. SQMRP optimizes routing selection, enhances measure accuracy and provides the guarantee of QoS. Routing protocol design and routing optimization policy based on jitter factor and so on are also discussed. In order to guarantee the security of the protocol, a security scheme based on improved Ariadne is presented, which can effectively withstand the tampering attack, forgery attack and conspiracy attack, etc.Finally, strand spaces model is used to prove respectively the correctness and security of TNSGKAP, SEGKM and SQMRP. EMAP and EMAP-P are also proved secure against existential forgery under adaptive chosen message and ID attack in the random oracle model. The performance analysis and simulation results show that the above proposed schemes can effectively reduce resource cost, adapt the characteristics of MANET and is clearly superior to the existing protocols.