<s>
The	O
Fast	O
Adaptive	O
and	O
Secure	O
Protocol	O
(	O
FASP	B-Protocol
)	O
is	O
a	O
proprietary	B-Application
data	O
transfer	O
protocol	O
.	O
</s>
<s>
FASP	B-Protocol
is	O
a	O
network-optimized	O
network	O
protocol	O
developed	O
by	O
Aspera	O
,	O
owned	O
by	O
IBM	O
.	O
</s>
<s>
Similar	O
to	O
the	O
connectionless	B-Protocol
UDP	B-Protocol
protocol	I-Protocol
,	O
FASP	B-Protocol
does	O
not	O
expect	O
any	O
feedback	O
on	O
every	O
packet	B-Protocol
sent	O
.	O
</s>
<s>
Only	O
the	O
packets	B-Protocol
marked	O
as	O
really	O
lost	O
must	O
be	O
requested	O
again	O
by	O
the	O
recipient	O
.	O
</s>
<s>
As	O
a	O
result	O
,	O
it	O
does	O
not	O
suffer	O
as	O
much	O
loss	O
of	O
throughput	O
as	O
TCP	B-Protocol
does	O
on	O
networks	O
with	O
high	O
latency	O
or	O
high	O
packet	B-Protocol
loss	I-Protocol
.	O
</s>
<s>
Amazon	B-Application
also	O
wants	O
to	O
use	O
the	O
protocol	O
for	O
uploading	O
to	O
data	O
centers	O
.	O
</s>
<s>
FASP	B-Protocol
has	O
built-in	O
security	O
mechanisms	O
that	O
do	O
not	O
affect	O
the	O
transmission	O
speed	O
.	O
</s>
<s>
Before	O
the	O
transfer	O
,	O
SSH	B-Protocol
is	O
used	O
for	O
key	O
exchange	O
for	O
authentication	O
.	O
</s>
<s>
The	O
data	O
is	O
optionally	O
encrypted	O
or	O
decrypted	O
immediately	O
before	O
sending	O
and	O
receiving	O
with	O
the	O
AES-128	B-Algorithm
.	O
</s>
<s>
To	O
counteract	O
attacks	O
by	O
monitoring	O
the	O
encrypted	O
information	O
during	O
long	O
transfers	O
,	O
the	O
AES	B-Algorithm
is	O
operated	O
in	O
cipher	O
feedback	O
mode	O
with	O
a	O
random	O
,	O
public	O
initialization	B-Algorithm
vector	I-Algorithm
for	O
each	O
block	O
.	O
</s>
<s>
In	O
addition	O
,	O
an	O
integrity	O
check	O
of	O
each	O
data	B-General_Concept
block	I-General_Concept
takes	O
place	O
,	O
in	O
which	O
case	O
,	O
for	O
example	O
,	O
a	O
man-in-the-middle	O
attack	O
would	O
be	O
noticed	O
.	O
</s>
<s>
FASP	B-Protocol
's	O
control	O
port	B-Protocol
is	O
TCP	B-Protocol
port	I-Protocol
22	O
the	O
same	O
port	B-Protocol
that	O
SSH	B-Protocol
uses	O
.	O
</s>
<s>
For	O
data	O
transfer	O
,	O
it	O
begins	O
at	O
UDP	B-Protocol
port	B-Protocol
33001	O
,	O
which	O
increments	O
with	O
each	O
additional	O
connection	O
thread	O
.	O
</s>
<s>
FASP	B-Protocol
's	O
flow	O
control	O
algorithm	O
,	O
unlike	O
TCP	B-Protocol
's	O
,	O
completely	O
ignores	O
packet	B-Protocol
drops	O
.	O
</s>
<s>
Instead	O
,	O
it	O
acts	O
on	O
changes	O
in	O
measured	O
packet	B-Protocol
delivery	O
time	O
.	O
</s>
<s>
By	O
contrast	O
,	O
TCP	B-Protocol
slowly	O
increases	O
its	O
rate	O
until	O
it	O
sees	O
a	O
packet	B-Protocol
drop	O
and	O
falls	O
back	O
,	O
interpreting	O
any	O
drop	O
as	O
congestion	O
.	O
</s>
<s>
On	O
a	O
channel	O
with	O
long	O
delay	O
and	O
frequent	O
packet	B-Protocol
loss	I-Protocol
,	O
TCP	B-Protocol
never	O
approaches	O
the	O
actual	O
bandwidth	O
available	O
.	O
</s>
<s>
FASP	B-Protocol
cooperates	O
with	O
TCP	B-Protocol
flows	O
on	O
the	O
same	O
channel	O
,	O
using	O
up	O
bandwidth	O
TCP	B-Protocol
leaves	O
unused	O
.	O
</s>
