Eliminating Scanning Delay using Advanced Neighbor Discovery with   Caching (ANDWC)
  The advance in wireless technologies and portable devices such as smart phones has made the Wireless Local Area Networks (WLANs) popular in the recent years. Nowadays, WLANs have become widely accepted in both private and public sectors due to ease of installation, reasonable prices and high data rates that can support real time applications. However, fast handoff required for such real-time applications is not provided in the current IEEE 802.11 specifications. Consequently, providing seamless mobility in these WLANs is an important issue. To solve this problem, a new fast handoff scheme called Advanced Neighbor Discovery with Caching (ANDWC) is proposed. This new mechanism is based on the user's mobility between two or more different Basic Service Sets (Layer 2 mobility). ANDWC can eliminate scanning delay (which contributes up to 90% of the total handoff latency) to provide seamless handoff by using pre-neighbor-discovery and caching mechanisms. 
Hassan Keshavarz, Ghaith A. Abdulwahed, Rosli Salleh, Laeth A. Abdul   Wahid
cs.NI