Abstract
Wireless ad-hoc networks are networks with the concept of self-configuration. With the absence of the fixed infrastructure, Wireless ad-hoc networks can dynamically change its topologies. Besides，there is no administrator in wireless ad-hoc network to manage and handle the principles of communication, access and route in the wireless ad-hoc network. According to the properties of wireless ad-hoc networks mentioned above, we know that all involved members in the wireless ad-hoc share the responsibility for routing, access, communications and so on. Moreover, such networks are more vulnerable to security threats than traditional wireless networks because of the absence of the fixed infrastructure. Among the different types of wireless ad-hoc network, Near-Term Digital Radio (NTDR) networks are wireless ad-hoc networks which follow the cluster-based principles. In past years, many secure communication schemes based on public key infrastructure (PKI) suited to cluster-based wireless ad-hoc network are proposed. Although the public key infrastructure is a well-known method for providing confidential communications in mobile wireless ad-hoc network, the computation load for the nodes in wireless ad-hoc network which only have constrained ability of computation and low bandwidth is heavy. For this reason，we take a deep research to design secure communication schemes in cluster-based wireless ad-hoc networks need light computation load and low communication bandwidth. Peer-to-peer (P2P) network is a design concept about how to provide the network services. There are two types of P2P networks: Hybrid and Pure. In hybrid P2P networks, there exist a more powerful trusted third party (TTP) which can provide additional ability of computation and storage. On the other hand, all the peers in pure P2P systems are treated the same and no powerful TTP exists. In P2P networks, the research about how to achieve the anonymity of service requesters or providers is interesting, especially how to make the service requesters and providers anonymous to each other. Besides, in order to prevent the anonymity from the data compromised from TTP due to attacks or normal broken, we hope to design applicable schemes which also provide the service requesters and providers’ anonymity to TTP. If we implement the idea about anonymity onto the cluster-based wireless ad-hoc network, we can treat the clusterheads as the peers in P2P networks and classify the cluster-based ad-hoc network into three categories depend on the presence of trust third party (TTP). First, the hybrid P2P networks which the TTP involved has powerful computation and high storage. Second, the hybrid P2P networks which the TTP involved is just treated as a trust server but only with some additional ability of computation and storage. The last one is the pure P2P networks which the TTP is absent. In this paper we propose the secure communication schemes for cluster-based wireless ad-hoc networks and the methods which can achieve the goal of mutual anonymity in either the hybrid or the pure P2P networks. For the secure communication schemes suited to cluster-based wireless ad-hoc network, instead of the use of public key infrastructures which need high computation load, we propose “ID-based” and “DH-based” two different schemes which do no need public key infrastructure but still promise the secure communication. As for the mutual anonymity in P2P networks, we proposed two schemes suited to hybrid P2P networks and one to pure P2P networks depend on the TTP’s ability of computation and storage.