<s>
HighSpeed	O
TCP	O
(	O
HSTCP	B-Protocol
)	O
is	O
a	O
congestion	O
control	O
algorithm	O
protocol	O
defined	O
in	O
RFC	O
3649	O
for	O
Transport	B-Protocol
Control	I-Protocol
Protocol	I-Protocol
(	O
TCP	O
)	O
.	O
</s>
<s>
HSTCP	B-Protocol
makes	O
minor	O
modifications	O
to	O
standard	O
TCP	O
's	O
congestion	O
control	O
mechanism	O
to	O
overcome	O
this	O
limitation	O
.	O
</s>
<s>
When	O
the	O
congestion	O
window	O
is	O
small	O
,	O
HSTCP	B-Protocol
behaves	O
exactly	O
like	O
standard	O
TCP	O
so	O
a(w )	O
is	O
1	O
and	O
b(w )	O
is	O
0.5	O
.	O
</s>
<s>
This	O
means	O
that	O
HSTCP	B-Protocol
's	O
window	O
will	O
grow	O
faster	O
than	O
standard	O
TCP	O
and	O
also	O
recover	O
from	O
losses	O
more	O
quickly	O
.	O
</s>
<s>
This	O
behavior	O
allows	O
HSTCP	B-Protocol
to	O
be	O
friendly	O
to	O
standard	O
TCP	O
flows	O
in	O
normal	O
networks	O
and	O
also	O
to	O
quickly	O
utilize	O
available	O
bandwidth	O
in	O
networks	O
with	O
large	O
bandwidth	O
delay	O
products	O
.	O
</s>
<s>
HSTCP	B-Protocol
has	O
the	O
same	O
slow	O
start/timeout	O
behavior	O
as	O
standard	O
TCP	O
.	O
</s>
<s>
Since	O
only	O
the	O
congestion	O
control	O
mechanism	O
is	O
modified	O
,	O
HSTCP	B-Protocol
can	O
be	O
used	O
with	O
other	O
TCP	O
options	O
like	O
SACK	O
.	O
</s>
