  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.
