An Enhanced Media Independent Handover Framework for Heterogeneous Networks

Seamless mobility in heterogeneous networks is difficult to be achieved because of various QoS requirements and complex heterogeneous network environments. Media independent handover (MIH) is used to handle such problem in IEEE 802.21 standard. However, only link layer dependent information is involved for the mobility decision. In this paper, an enhanced media independent handover (EMIH) framework and mobility management mechanism are proposed, in which new function entities (FEs) and modules are defined and used to provide link layer and application layer information from client side and network side to mobility decision engine. Compared with MIH, the EMIH provides more sufficient and comprehensive trigger events. The static and dynamic information are collected flexibly at mobile node (MN) and within the network infrastructure. Various handover types are designed to make use of such information to optimize the handover, which is illustrated by an example in this paper. The proposed EMIH architecture can benefit not only mobile users, but also network operators.