Mobile devices and access points clearly need to implement MIHF in order to communicate in a standard way between each other and between the wireless and IP layers. This allows them to make their own local decisions as to whether and how to handover a session. The reason for MIHF in core network equipment with no wireless interface is to enable the design of “handover servers” which can make centralized decisions about the handover of sessions among multiple access points and multiple access technologies. Such servers allow a wireless network operator to balance the traffic load so as to alleviate congestion on specific access points, and deliver sufficient QoS to all users.