The objective of the Transmission Control Protocol (TCP) is to
provide reliable end-to-end delivery of data over unreliable networks. Over
the past few years, the problem of congestion control has received widespread
attention, both in the Internet as well as in the ad-hoc network context.
In these networks, however packet losses occur more often due to unreliable
links than to congestion. But each packet loss on the wireless link results in
invoking congestion control measures at the source, which leads to severe
performance degradation of the TCP.
Many authors have reported that the TCP interacts with the lower
layers, but still it cannot predict route failures and network congestion. On the
other hand, considerable research has been carried out to show how the TCP
performance is significantly affected by MAC protocols in multi-hop & adhoc
networks.
The issues discussed above, with the possibility of further avenues
for improving the TCP performance in multihop wireless networks, served as
the motivation and basis for the proposed work. The proposed work describes
the efficient techniques in various layers to improve the TCP performance
over wireless networks. In the data link layer, the link RED (Random Early
Discard) technique seeks to react earlier to link overload, and it solves the
hidden terminal problem. As well as, the Adaptive Pacing Technique seeks to
improve spatial reuse, and it solves the exposed terminal problem.
