<s>
H-TCP	B-Protocol
is	O
another	O
implementation	O
of	O
TCP	B-Protocol
with	O
an	O
optimized	O
congestion	O
control	O
algorithm	O
for	O
high	O
speed	O
networks	O
with	O
high	O
latency	O
(	O
LFN	O
:	O
Long	O
Fat	O
Networks	O
)	O
.	O
</s>
<s>
H-TCP	B-Protocol
is	O
an	O
optional	O
module	O
in	O
Linux	B-Application
since	O
kernel	B-Operating_System
version	O
2.6	O
,	O
and	O
has	O
been	O
implemented	O
for	O
FreeBSD	O
7	O
.	O
</s>
<s>
H-TCP	B-Protocol
is	O
a	O
loss-based	B-Protocol
algorithm	O
,	O
using	O
additive-increase/multiplicative	O
-decrease	O
(	O
AIMD	O
)	O
to	O
control	O
TCP	B-Protocol
's	O
congestion	O
window	O
.	O
</s>
<s>
It	O
is	O
one	O
of	O
many	O
TCP	B-Protocol
congestion	O
avoidance	O
algorithms	O
which	O
seeks	O
to	O
increase	O
the	O
aggressiveness	O
of	O
TCP	B-Protocol
on	O
high	O
bandwidth-delay	O
product	O
(	O
BDP	O
)	O
paths	O
,	O
while	O
maintaining	O
"	O
TCP	B-Protocol
friendliness	O
"	O
for	O
small	O
BDP	O
paths	O
.	O
</s>
<s>
H-TCP	B-Protocol
increases	O
its	O
aggressiveness	O
(	O
in	O
particular	O
,	O
the	O
rate	O
of	O
additive	O
increase	O
)	O
as	O
the	O
time	O
since	O
the	O
previous	O
loss	O
increases	O
.	O
</s>
<s>
This	O
avoids	O
the	O
problem	O
encountered	O
by	O
HSTCP	B-Protocol
and	O
BIC	B-Protocol
TCP	I-Protocol
of	O
making	O
flows	O
more	O
aggressive	O
if	O
their	O
windows	O
are	O
already	O
large	O
.	O
</s>
<s>
Thus	O
,	O
new	O
flows	O
can	O
be	O
expected	O
to	O
converge	O
to	O
fairness	O
faster	O
under	O
HTCP	B-Protocol
than	O
HSTCP	B-Protocol
and	O
BIC	B-Protocol
TCP	I-Protocol
.	O
</s>
<s>
A	O
side	O
effect	O
of	O
increasing	O
the	O
rate	O
of	O
increase	O
as	O
the	O
time	O
since	O
the	O
last	O
packet	B-Protocol
loss	I-Protocol
increases	O
,	O
is	O
that	O
flows	O
which	O
happen	O
not	O
to	O
lose	O
a	O
packet	O
when	O
other	O
flows	O
do	O
,	O
can	O
then	O
take	O
an	O
unfair	O
portion	O
of	O
the	O
bandwidth	O
.	O
</s>
<s>
The	O
Linux	B-Application
implementation	O
of	O
H-TCP	B-Protocol
also	O
has	O
an	O
option	O
for	O
avoiding	O
"	O
RTT	O
unfairness	O
"	O
,	O
which	O
occurs	O
in	O
TCP	B-Protocol
Reno	O
,	O
but	O
is	O
a	O
particular	O
problem	O
for	O
most	O
high	O
speed	O
variants	O
of	O
TCP	B-Protocol
(	O
although	O
not	O
FAST	B-Protocol
TCP	I-Protocol
)	O
.	O
</s>
<s>
The	O
algorithm	O
was	O
initially	O
introduced	O
as	O
H-TCP	B-Protocol
,	O
without	O
mention	O
of	O
what	O
the	O
'	O
H	O
 '	O
stands	O
for	O
.	O
</s>
<s>
However	O
,	O
it	O
is	O
often	O
called	O
"	O
Hamilton	O
TCP	B-Protocol
"	O
,	O
for	O
the	O
Hamilton	O
Institute	O
where	O
it	O
was	O
created	O
.	O
</s>
