IEEE 802.21 MIH in Linux Kernel space for cognitive and smart handovers

This paper proposes an implementation of IEEE 802.21 MIH (Media Independent Handover) in Linux kernel space for cognitive and smart handovers. In the proposed scheme, the surrounding wireless access network information is collected and provided by IEEE 802.21 MIH, and the mobile node (MN) performs time-limited smart scanning with interleaved packet delivery for target access point. For better performance, the MIH functions have been implemented as Linux kernel modules that minimize the overheads in event notification and command processing. During the smart channel scanning,MIH is used to inform the change of MN's operation mode to network (e.g., MAG - mobile access gateway), asking the buffering of downlink packets during the smart scanning. The smart scanning is controlled to limit the service interruption time to be less than 50 ms, in order to guarantee the QoS requirement of realtime multimedia service, especially jitter and packet loss. The overall performances of the MIH operations and QoS provisioning are analyzed in detail. The proposed IEEE 802.21 MIH on Linux kernel can support various horizontal and vertical handovers across heterogeneous wireless access networks for QoS-guaranteed seamless realtime service provisioning1.