A Comprehensive Survey on Vertical Handover Security Attacks during Execution Phase

The Mobile Users' demand (MUs) in getting Always Best Connected (ABC) is on the increase by using different Radio Access Technologies (RATs): Wi-Fi, GSM (2G), UMTS (3G), LTE (4G) and 5G. To fulfill the ABC, three phases of Vertical Handover (VHO) are required: Initiation, Decision and Execution. The importance of the security factor particularly arises during the execution phase where the mobility management protocols are taken place: Mobile IPv4 (MIPv4) and Mobile IPv6 (MIPv6). This paper therefore surveys the current research initiatives on VHO security attacks during execution phase in order to precisely identify the active security challenges.