Mobile IPv6 Vertical Handover Specifications, Threats, and Mitigation Methods: A Survey

Internet users have grown substantially over the last decade, especially following the emergence of mobile technology. Most Internet connections nowadays are accessed using mobile devices in order to stay connected all the time and everywhere. Owing to the limited coverage of such access points as well as base stations, mobile devices are required to handover connectivity if there is a move to other locations. Horizontal handover is conducted when the movement is within the same network. Otherwise, there must be vertical handover when external network infrastructure is encountered. However, as the Internet is an open network that naturally lacks trust between users, the mobile nodes that move to an external network are susceptible to various attacking activities. Compromising mobile nodes may cause users to lose their data as well as destroy their mobile devices in terms of both software and hardware. Securing mobile devices is crucial in order to avoid losses in terms of not only money but also facilities. Although mobile nodes have been developed with certain security features, some researchers have found vulnerabilities. This paper surveys in detail the security vulnerabilities of mobile IPv6 vertical handover and the current relevant mitigation methods. Furthermore, we describe the mechanism of mobile IPv6 vertical handover and its security vulnerability as well as security mechanisms proposed by researchers. Based on the survey, there are apparently weaknesses in current security features that are in need of solutions to minimize the effect of malicious activities. An open direction of future research on mobile IPv6 vertical handover security is elaborated at the end of this paper.