<s>
Iperf	B-Language
is	O
a	O
tool	O
for	O
network	O
performance	O
measurement	O
and	O
tuning	O
.	O
</s>
<s>
It	O
is	O
a	O
cross-platform	B-Operating_System
tool	I-Operating_System
that	O
can	O
produce	O
standardized	O
performance	O
measurements	O
for	O
any	O
network	O
.	O
</s>
<s>
Iperf	B-Language
has	O
client	B-Protocol
and	O
server	B-Application
functionality	O
,	O
and	O
can	O
create	O
data	B-General_Concept
streams	I-General_Concept
to	O
measure	O
the	O
throughput	O
between	O
the	O
two	O
ends	O
in	O
one	O
or	O
both	O
directions	O
.	O
</s>
<s>
Typical	O
iperf	B-Language
output	O
contains	O
a	O
time-stamped	O
report	O
of	O
the	O
amount	O
of	O
data	O
transferred	O
and	O
the	O
throughput	O
measured	O
.	O
</s>
<s>
The	O
data	B-General_Concept
streams	I-General_Concept
can	O
be	O
either	O
Transmission	B-Protocol
Control	I-Protocol
Protocol	I-Protocol
(	O
TCP	O
)	O
or	O
User	B-Protocol
Datagram	I-Protocol
Protocol	I-Protocol
(	O
UDP	O
)	O
:	O
</s>
<s>
UDP	O
:	O
When	O
used	O
for	O
testing	O
UDP	O
capacity	O
,	O
iperf	B-Language
allows	O
the	O
user	O
to	O
specify	O
the	O
datagram	O
size	O
and	O
provides	O
results	O
for	O
the	O
datagram	O
throughput	O
and	O
the	O
packet	B-Protocol
loss	O
.	O
</s>
<s>
TCP	O
:	O
When	O
used	O
for	O
testing	O
TCP	O
capacity	O
,	O
iperf	B-Language
measures	O
the	O
throughput	O
of	O
the	O
payload	O
.	O
</s>
<s>
Iperf	B-Language
uses	O
1024	O
×	O
1024	O
for	O
mebibytes	O
and	O
1000	O
×	O
1000	O
for	O
megabytes	O
.	O
</s>
<s>
Iperf	B-Language
is	O
open-source	B-Application
software	I-Application
written	O
in	O
C	B-Language
,	O
and	O
it	O
runs	O
on	O
various	O
platforms	O
including	O
Linux	B-Application
,	O
Unix	B-Application
and	O
Windows	B-Application
(	O
either	O
natively	O
or	O
inside	O
Cygwin	B-Language
)	O
.	O
</s>
<s>
Iperf	B-Language
is	O
a	O
compatible	O
reimplementation	O
of	O
the	O
ttcp	B-Protocol
program	O
that	O
was	O
developed	O
at	O
the	O
National	B-General_Concept
Center	I-General_Concept
for	I-General_Concept
Supercomputing	I-General_Concept
Applications	I-General_Concept
at	O
the	O
University	O
of	O
Illinois	O
by	O
the	O
Distributed	O
Applications	O
Support	O
Team	O
(	O
DAST	O
)	O
of	O
the	O
National	O
Laboratory	O
for	O
Applied	O
Network	O
Research	O
(	O
NLANR	O
)	O
,	O
which	O
was	O
shut	O
down	O
on	O
December	O
31	O
,	O
2006	O
,	O
on	O
termination	O
of	O
funding	O
by	O
the	O
United	O
States	O
National	O
Science	O
Foundation	O
.	O
</s>
<s>
Iperf3	B-Language
is	O
a	O
rewrite	O
of	O
iperf	B-Language
from	O
scratch	O
to	O
create	O
a	O
smaller	O
,	O
simpler	O
code	O
base	O
.	O
</s>
<s>
Another	O
change	O
is	O
that	O
iperf3	B-Language
is	O
single	O
threaded	O
while	O
iperf2	O
is	O
multi-threaded	O
.	O
</s>
<s>
Iperf3	B-Language
was	O
started	O
in	O
2009	O
,	O
with	O
the	O
first	O
release	O
in	O
January	O
2014	O
.	O
</s>
<s>
Iperf3	B-Language
is	O
not	O
backwards	B-General_Concept
compatible	I-General_Concept
with	O
iperf2	O
.	O
</s>
<s>
does	O
n't	O
officially	O
support	O
Windows	B-Application
,	O
only	O
Linux	B-Application
.	O
</s>
<s>
did	O
compile	O
it	O
to	O
Windows	B-Application
back	O
in	O
2016	O
but	O
has	O
n't	O
been	O
maintained	O
since	O
.	O
</s>
<s>
A	O
user	O
of	O
Neowin	O
,	O
has	O
since	O
been	O
compiling	O
the	O
latest	O
Windows	B-Application
versions	O
of	O
Iperf	B-Language
and	O
maintains	O
them	O
on	O
his	O
.	O
</s>
<s>
Linux	B-Application
versions	O
information	O
and	O
builds	O
are	O
still	O
actively	O
developed	O
.	O
</s>
<s>
Most	O
Current	O
Linux	B-Application
distributions	O
have	O
up-to-date	O
versions	O
of	O
iperf3	B-Language
in	O
their	O
native	O
package	O
repositories	O
(	O
as	O
of	O
1	O
.	O
</s>
