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International Journal of Scientific and Engineering Research
ISSN Online 2229-5518
ISSN Print: 2229-5518 11    
Website: http://www.ijser.org
scirp IJSER >> Volume 2, Issue 11, November 2011
Reducing Layer 2 Handoff Latency in WLANs using Advanced Context Distribution
Full Text(PDF, 3000)  PP.  
Laeth A. Al-Rawi, Rosli Salleh, Ghaith A. Al-Rawi, Hassan A. Al-Rawi, H.Keshavarz
IEEE 802.11, WLANs, IAPP, Hand-off Latency
WLANs have experienced very fast deployment in both public and private areas over recent years. They provide nontrivial replacement for the complicated and high cost wired LANs. However, the Access Points that WLANs are build from do not have very wide coverage range (usually under 100m indoors). Consequently, many handoffs occur as the mobile host moves while accessing the network resources located at the distribution system. Unfortunately, these handoffs can disturb real time applications if they take too long (more than 50ms). In order to resolve this problem, this paper introduces a new mechanism for reducing handoff delay called Advanced Context Distribution (ACD). ACD is able to reduce re-association phase delay by eliminating Inter Access Point Protocol (IAPP) excess time consumed for transferring station context information from the old access point to the new associated access point (up to 40ms delay).
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