Simultaneous mobility: analytical framework, theorems and solutions

The original Mobile IP (MIP) protocol does not perform route optimisation but uses Home Agents to forward traffic. Thus, it does not have problems with simultaneous mobility, i.e., the special case when both end hosts are mobile and move at about the same time. However, MIP for IPv6 (MIPv6) uses binding updates that are sent directly to a correspondent node. Session Initiation Protocol based mobility management (SIPMM) and MIP with Location Registers (MIP-LR) also use direct binding updates between a Mobile Host and a correspondent node. Thus, MIPv6, MIP-LR, and SIPMM are vulnerable to the simultaneous mobility problem. In this paper, we analyse the simultaneous mobility problem and solution mechanisms, and propose new ways for MIPv6, MIP-LR and SIPMM to handle simultaneous mobility.