<s>
Microsoft	B-General_Concept
Notification	I-General_Concept
Protocol	I-General_Concept
(	O
MSNP	B-General_Concept
,	O
also	O
known	O
as	O
the	O
Mobile	B-General_Concept
Status	I-General_Concept
Notification	I-General_Concept
Protocol	I-General_Concept
)	O
is	O
an	O
instant	B-Application
messaging	I-Application
protocol	O
developed	O
by	O
Microsoft	O
for	O
use	O
by	O
the	O
Microsoft	O
Messenger	O
service	O
and	O
the	O
instant	B-Application
messaging	I-Application
clients	O
that	O
connect	O
to	O
it	O
,	O
such	O
as	O
Skype	B-Application
since	O
2014	O
,	O
and	O
the	O
earlier	O
Windows	B-Protocol
Live	I-Protocol
Messenger	I-Protocol
,	O
MSN	B-Protocol
Messenger	I-Protocol
,	O
Windows	B-Application
Messenger	I-Application
,	O
and	O
Microsoft	O
Messenger	O
for	O
Mac	O
.	O
</s>
<s>
Third-party	O
clients	O
such	O
as	O
Pidgin	B-Protocol
and	O
Trillian	B-Protocol
can	O
also	O
communicate	O
using	O
the	O
protocol	O
.	O
</s>
<s>
MSNP	B-General_Concept
was	O
first	O
used	O
in	O
a	O
publicly	O
available	O
product	O
with	O
the	O
first	O
release	O
of	O
MSN	B-Protocol
Messenger	I-Protocol
in	O
1999	O
.	O
</s>
<s>
Any	O
major	O
change	O
made	O
to	O
the	O
protocol	O
,	O
such	O
as	O
a	O
new	O
command	O
or	O
syntax	O
changes	O
,	O
results	O
in	O
a	O
version-number	O
incremented	O
by	O
one	O
in	O
the	O
format	O
of	O
MSNP#	O
.	O
</s>
<s>
Starting	O
on	O
September	O
11	O
,	O
2007	O
,	O
Microsoft	O
forces	O
most	O
current	O
users	O
of	O
MSN	B-Protocol
Messenger	I-Protocol
to	O
upgrade	O
to	O
Windows	B-Protocol
Live	I-Protocol
Messenger	I-Protocol
8.1	O
due	O
to	O
security	O
considerations	O
.	O
</s>
<s>
MSNP3	O
,	O
4	O
,	O
and	O
5	O
were	O
supported	O
by	O
the	O
Messenger	O
servers	O
by	O
July	O
2000	O
and	O
used	O
by	O
MSN	B-Protocol
Messenger	I-Protocol
3.0	O
and	O
4.0	O
.	O
</s>
<s>
MSNP6	O
was	O
used	O
by	O
later	O
versions	O
of	O
MSN	B-Protocol
Messenger	I-Protocol
4.x	O
.	O
</s>
<s>
In	O
2002	O
MSN	B-Protocol
Messenger	I-Protocol
5.0	O
used	O
MSNP7	O
.	O
</s>
<s>
Version	O
5.0	O
of	O
MSN	B-Protocol
Messenger	I-Protocol
is	O
the	O
only	O
one	O
that	O
uses	O
this	O
MSNP	B-General_Concept
version	O
.	O
</s>
<s>
Windows	B-Application
Messenger	I-Application
uses	O
MSNP8	O
as	O
its	O
standard	O
version	O
,	O
including	O
4.7	O
up	O
to	O
the	O
latest	O
5.1	O
.	O
</s>
<s>
MSNP9	O
was	O
introduced	O
with	O
MSN	B-Protocol
Messenger	I-Protocol
6	O
,	O
adding	O
support	O
for	O
"	O
D	O
type	O
"	O
(	O
data	O
)	O
messages	O
,	O
which	O
are	O
used	O
for	O
transferring	O
display	O
pictures	O
and	O
custom	O
emoticons	O
between	O
clients	O
,	O
frame-by-frame	O
web	O
cam	O
(	O
rather	O
than	O
a	O
traditional	O
stream	O
like	O
Windows	B-Device
Media	I-Device
Player	I-Device
's	O
WMV	B-Device
format	O
)	O
and	O
an	O
improved	O
voice	O
system	O
,	O
as	O
well	O
as	O
improved	O
NAT	B-Protocol
traversal	O
for	O
file	O
transfers	O
.	O
</s>
<s>
Employed	O
in	O
MSN	B-Protocol
Messenger	I-Protocol
6.1	O
,	O
after	O
Microsoft	O
started	O
blocking	O
earlier	O
versions	O
in	O
October	O
2003	O
.	O
</s>
<s>
However	O
,	O
it	O
was	O
not	O
a	O
big	O
overhaul	O
,	O
the	O
only	O
obvious	O
change	O
was	O
integration	O
with	O
Hotmail	B-Operating_System
address	O
books	O
.	O
</s>
<s>
Employed	O
by	O
Windows	B-Protocol
Live	I-Protocol
Messenger	I-Protocol
8.0	I-Protocol
,	O
MSNP13	O
features	O
a	O
lot	O
of	O
changes	O
.	O
</s>
<s>
Most	O
notably	O
,	O
contact	O
list	O
synchronization	O
has	O
been	O
removed	O
and	O
clients	O
must	O
instead	O
send	O
a	O
SOAP	B-Application
request	O
to	O
a	O
contacts	O
server	O
,	O
also	O
known	O
as	O
"	O
Client	O
goes	O
to	O
ABCH	O
"	O
(	O
where	O
ABCH	O
stands	O
for	O
Address	O
Book	O
Clearing	O
House	O
,	O
the	O
address	O
book	O
service	O
behind	O
all	O
MSN	B-Protocol
and	O
Windows	O
Live	O
services	O
)	O
.	O
</s>
<s>
MSNP15	O
is	O
the	O
protocol	O
version	O
introduced	O
with	O
Windows	B-Protocol
Live	I-Protocol
Messenger	I-Protocol
8.1	O
on	O
2006-09-08	O
.	O
</s>
<s>
Furthermore	O
,	O
support	O
for	O
user	O
locations	O
has	O
been	O
added	O
to	O
the	O
Personal	O
Status	O
Message	O
,	O
although	O
this	O
feature	O
was	O
later	O
removed	O
from	O
the	O
Windows	B-Protocol
Live	I-Protocol
Messenger	I-Protocol
8.1	O
client	O
.	O
</s>
<s>
MSNP16	O
is	O
used	O
in	O
a	O
pre-release	O
version	O
of	O
Windows	B-Protocol
Live	I-Protocol
Messenger	I-Protocol
9.0	O
,	O
leaked	O
in	O
December	O
2007	O
.	O
</s>
<s>
The	O
UUX	O
data	O
have	O
been	O
extended	O
to	O
contain	O
Endpoint	O
Data	O
(	O
also	O
MPOP	O
)	O
,	O
as	O
well	O
as	O
Signature	O
Sound	O
MSN	B-Protocol
Object	O
Data	O
.	O
</s>
<s>
MSNP17	O
is	O
identified	O
by	O
Windows	B-Protocol
Live	I-Protocol
Messenger	I-Protocol
servers	O
on	O
messenger.hotmail.com,	O
but	O
unused	O
by	O
any	O
official	O
client	O
released	O
by	O
Microsoft	O
.	O
</s>
<s>
MSNP18	O
is	O
used	O
in	O
Windows	B-Protocol
Live	I-Protocol
Messenger	I-Protocol
2009	O
(	O
14.0	O
)	O
.	O
</s>
<s>
UUX	O
Data	O
have	O
been	O
extended	O
to	O
include	O
Scene	O
image	O
MSN	B-Protocol
Object	O
data	O
.	O
</s>
<s>
Employed	O
by	O
Skype	B-Application
since	O
early	O
2014	O
.	O
</s>
<s>
Also	O
used	O
by	O
Microsoft	B-Application
Teams	I-Application
.	O
</s>
