A novel mix-based location privacy mechanism in Mobile IPv6

Mobile IP (MIP), a link-layer-independent protocol, is suitable for Internet Protocol (IP) based mobility across homogeneous media as well as heterogeneous networks. Mobile IPv6 (MIPv6) not only possesses the major characteristics of Mobile IPv4 (MIPv4), but also has more advantages such as the expansion of address space and elimination of the “triangle routing”, which make MIPv6 the most suitable candidate for future heterogeneous environment. Location privacy is very important for mobile node (MN) in mobile communications because exposure of the relationship between MN's real physical location and its identity will lead to serious violation of the MN's privacy. And the attackers can easily launch the traffic analysis attack according to such revealed relationship. However, the location privacy of MN to avoid attackers tracing in MIP is not paid more attention up to the present. As the most widely used anonymous communication technology, mix-network can be used to provide the location privacy in MIP. In this paper, we employ the practical mix-network to provide location privacy on signaling control information in MIPv6. By utilizing the practical mix-network, a novel MIPv6 network model is proposed. Based on the network model, a new location privacy extension to MN's home binding and correspondent registration in MIPv6 is proposed and it can be integrated into MIPv6 easily. As a result, our location privacy proposal possesses the benefits succeeded from the adopted practical mix-network, e.g. reducing the trust requirements among the mix servers and increasing the robustness compared with other mix-based MIP location privacy schemes. In addition, the computation load in MN does not increase significantly during the binding procedures according to the analysis, thus it is more suitable for the asymmetric wireless environment.