TCP performance for WLAN-GPRS handover in an Intermediate Switching Network based framework

In heterogeneous wireless mobile networks, the performance of TCP traffic degrades as it faces severe challenges due to packet loss, out-of-order delivery, connection breakdown etc. during vertical handover. In this paper, the performance of TCP traffic is evaluated over a loosely coupled architectural framework, based on Intermediate Switching Network (ISN), for vertical handover between GPRS and 802.11 networks [1]. A modified TCP scheme, ISN-TCP is proposed that can handle the above problems using a cross layer interaction between Network and Transport layer. Simulation result shows that ISN-TCP improves the performance over TCP-newReno in ISN based vertical handover between GPRS and WLAN.