The invention provides a mobility managing system and method for an integrated identifier network as well as a routing method. In the integrated identifier network, the mobility managing system based on DHT (distributed hash table) is provided, so that the system has good load balance and expandability, burden on a mapping server is alleviated by a local buffer, and the time of establishing communication and time delay of data forwarding are shortened; the Overlay routine method and the mobility managing method which are based on MDP (Markov decision process) are provided, therefore the method has the characteristic of distributive computation, and can be used for balancing and reducing the complexity of time and space, and effectively avoiding a loop and abundant redundancy computation so that the methods are suitable for a large scale mobility management; and by utilizing the methods, a remuneration function is defined by combining physical layer and application layer information, thereby reducing the influence resulting from topology inconformity between an Overlay network and a physical network to a certain extent, and optimizing the update and query performance of a mobility management mechanism.