Wireless Handoff Optimization: A Comparison of IEEE 802.11r and HOKEY

  • Kashif Nizam Khan
  • Jinat Rehana
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6164)


IEEE 802.11 or Wi-Fi has long been the most widely deployed technology for wireless broadband Internet access, yet it is increasingly facing competition from other technologies such as packet-switched cellular data. End user expectations and demands have grown towards a more mobile and agile network. At one end, users demand more and more mobility and on the other end, they expect a good QoS which is sufficient to meet the needs of VoIP and streaming video. However, as the 4G technologies start knocking at doors, 802.11 is being questioned for its mobility and QoS (Quality of Service). Unnecessary handoffs and re-authentication during handoffs result in higher latencies. Recent research shows that if the handoff latency is high, services like VoIP experience excessive jitter. Bulk of the handoff latency is caused by security mechanisms, such as the 4-way handshake and, in particular, EAP authentication to a remote authentication server. IEEE 802.11r and HandOver KEY (HOKEY) are protocol enhancements that have been introduced to mitigate these challenges and to manage fast and secure handoffs in a seamless manner. 802.11r extends the 802.11 base specification to support fast handoff in the MAC protocol. On the other hand, HOKEY is a suite of protocols standardized by IETF to support fast handoffs. This paper analyzes the applicability of 802.11r and HOKEY solutions to enable fast authentication and fast handoffs. It also presents an overview of the fast handoff solutions proposed in some recent research.


Mobile Node Medium Access Control Access Point Medium Access Control Protocol Medium Access Control Layer 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Kashif Nizam Khan
    • 1
  • Jinat Rehana
    • 1
  1. 1.Norwegian University of Science and Technology, NTNU, Helsinki University of Technology, TKK 

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