A Simplified FT protocol over Software-Defined WLAN

Abstract

The fast BSS transition (FT) is defined to support intra-ESS mobility at the IEEE 802.11 network. In the FT protocol, authentication and reassociation messages piggyback the parameters for a new session key generation. When a station changes its point of attachment from the current access point(AP) to the target AP, the supplicant key holders of the station and associator key holders in the current AP and the target AP interact to simplify the authentication and a new session key generation processes. We propose a simplified FT protocol to achieve a faster FT for the IEEE 802.11 network over SDN. In SDN, associator key holders can locate at the centralized SDN controller, so an integrated key holder can replace associator key holders of APs. As a result, the simplified FT protocol re-associates the station and the target AP with a single message exchange (two messages) instead of two message exchanges (four messages).