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An Enhanced Inter-Access Point Protocol for Uniform Intra and Intersubnet Handoffs
July/August 2005 (vol. 4 no. 4)
pp. 321-334
An enhanced IEEE 802.11 Inter-Access Point Protocol (IAPP) is proposed to provide a unified solution for both intra and intersubnet handoff processes. The proposed enhancement relies on the access point's (AP's) interoperability with other APs, provided by the IP-based IAPP, so as to enable the intra and intersubnet link-layer frame buffering-and-forwarding. This enhancement not only eliminates frame losses during an intrasubnet handoff but, more importantly, realizes loss-free, fast intersubnet handoffs without modifying the IP-mobility protocols such as Mobile IP. Our ns-2-based simulation results show that the intersubnet handoff process is transparent to the mobile host's TCP session. Moreover, the enhanced IAPP supports higher user mobility and achieves a higher TCP throughput—up to 50 percent improvement over the original IAPP.

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Index Terms:
Index Terms- Mobile IP, IEEE 802.11 wireless LAN, fast/smooth handoff, TCP performance.
Chun-Ting Chou, Kang G. Shin, "An Enhanced Inter-Access Point Protocol for Uniform Intra and Intersubnet Handoffs," IEEE Transactions on Mobile Computing, vol. 4, no. 4, pp. 321-334, July-Aug. 2005, doi:10.1109/TMC.2005.49
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