TCP Behaviour with Changes in Access Link Bandwidth and Delay During Vertical Handoffs

In this paper we study TCP performance in the presence of vertical handoffs between access networks with widely varying link characteristics. TCP being an end-to-end protocol has performance problems as its behaviour depends on the end-to-end path characteristics which are likely to be affected by a vertical handoff. We carry out a systematic study of TCP behaviour and the consequent problems that arise in various handoff scenarios between networks with different bandwidth and delay characteristics. This study can serve as a basis to evaluate any modifications to the TCP algorithm to adapt to a vertical handoff.