Mobile IP gives solutions to wireless applications to maintain the connectivity while handover is occurred. However, a remote home agent can result in poor efficiency. Dynamic home agent reassignment model is proposed to reduce both the signalling traffic and the data traffic to the home network. Therefore, it has to be assured that there are enough home agents available; otherwise, it is hardly to pick one home agent resulting in good performance.In this paper, a dynamic home agent selection in peer-to-peer overlay networks is proposed. Users are responsible to play the role of home agent sometimes. The Overlay association table is referred. Mobile relay assignment and mobile relay redirection are addressed.Due to the previous work, a software agent has been presented to perform the undercover maintenance of connectivity at the application layer for handling the mobility in all-IP networks. It gives an end-to-end handover solution via proxy-based component using API hooking technology. There are no equipments added, no change of protocol stack and no modification on existing services. While a peer node performs handover, services will not be aware of packets re-directing to the new destination address. An experimental testbed is presented for performance measurement.