Wireless networks and mobile computing technologies are having a profound impact on IP-based networks, as their basic protocols were designed without assuming mobility of the network nodes. More recently, protocols like Mobile IP have been designed to handle global mobility, and micro-mobility protocols have been proposed for their management of intra-mobility. However, these protocols do not address important issues required for seamless mobility, such as candidate access router discovery, target access router determination, and context transfer. In this paper, we identify the problems related to seamless mobility, underline design considerations to be observed when designing seamless mobility solutions and propose an architecture that can be used as a framework for the implementation of these solutions.