  Transmission Control Protocol (TCP) has been profusely used by most of
internet applications. Since 1970s, several TCP variants have been developed in
order to cope with the fast increasing of network capacities especially in high
Bandwidth Delay Product (high-BDP) networks. In these TCP variants, several
approaches have been used, some of these approaches have the ability to
estimate available bandwidths and some react based on network loss and/or delay
changes. This variety of the used approaches arises many consequent problems
with different levels of dependability and accuracy. Indeed, a particular TCP
variant which is proper for wireless networks, may not fit for high-BDP wired
networks and vice versa. Therefore, it is necessary to conduct a comparison
between the high-speed TCP variants that have a high level of importance
especially after the fast growth of networks bandwidths. In this paper,
high-speed TCP variants, that are implemented in Linux and available for
research, have been evaluated using NS2 network simulator. This performance
evaluation presents the advantages and disadvantages of these TCP variants in
terms of throughput, loss-ratio and fairness over high-BDP networks. The
results reveal that, CUBIC and YeAH overcome the other highspeed TCP variants
in different cases of buffer size. However, they still require more improvement
to extend their ability to fully utilize the high-speed bandwidths, especially
when the applied buffer is near-zero or less than the BDP of the link.
