<s>
Yate	B-Language
(	O
Yet	O
Another	O
Telephony	O
Engine	O
)	O
is	O
free	B-Application
and	O
open	B-Application
source	I-Application
communications	O
software	O
with	O
support	O
for	O
video	O
,	O
voice	O
and	O
instant	O
messaging	O
.	O
</s>
<s>
It	O
is	O
an	O
extensible	O
PBX	O
under	O
the	O
GPL	B-License
2.0only	O
license	O
.	O
</s>
<s>
It	O
is	O
written	O
in	O
C++	B-Language
with	O
a	O
modular	O
design	O
,	O
allowing	O
the	O
use	O
of	O
scripting	O
languages	O
like	O
Perl	B-Language
,	O
Python	B-Language
and	O
PHP	B-Application
to	O
create	O
external	O
functionality	O
.	O
</s>
<s>
In	O
2004	O
,	O
NullTeam	O
,	O
the	O
company	O
behind	O
Yate	B-Language
,	O
launched	O
the	O
official	O
website	O
.	O
</s>
<s>
In	O
2005	O
Sangoma	O
announced	O
their	O
support	O
for	O
Yate	B-Language
development	O
on	O
the	O
Microsoft	B-Application
Windows	I-Application
platform	O
.	O
</s>
<s>
On	O
May	O
4	O
,	O
2011	O
,	O
sipgate	O
announced	O
that	O
it	O
had	O
chosen	O
the	O
Yate	B-Language
project	O
for	O
its	O
core	O
infrastructure	O
.	O
</s>
<s>
Yate	B-Language
version	O
5.0	O
was	O
released	O
in	O
January	O
2014	O
.	O
</s>
<s>
Yate	B-Language
's	O
architecture	O
is	O
based	O
on	O
a	O
message	B-Architecture
passing	I-Architecture
system	O
.	O
</s>
<s>
Core	O
,	O
where	O
encapsulations	O
for	O
sockets	B-Protocol
,	O
threads	B-Operating_System
and	O
other	O
primitives	O
can	O
be	O
found	O
.	O
</s>
<s>
Yate	B-Language
Modules	O
,	O
modules	O
extending	O
the	O
functionality	O
of	O
Yate	B-Language
,	O
not	O
necessarily	O
telephony-related	O
.	O
</s>
<s>
A	O
2006	O
O'Reilly	O
Emerging	O
Telephony	O
review	O
shows	O
that	O
Yate	B-Language
offers	O
flexibility	O
via	O
the	O
external	O
text	O
protocol	O
.	O
</s>
<s>
Because	O
of	O
this	O
,	O
it	O
is	O
fairly	O
easy	O
to	O
mix	O
telephony-related	O
functions	O
with	O
text-based	O
protocols	O
like	O
HTTP	B-Protocol
,	O
SMTP	B-Protocol
or	O
an	O
interface	O
with	O
a	O
database	O
via	O
SQL	B-Language
.	O
</s>
<s>
Currently	O
YAYPM	O
is	O
the	O
most	O
advanced	O
connector	O
library	O
and	O
uses	O
Python	B-Language
with	O
the	O
Twisted	B-Language
framework	O
for	O
rapid	O
development	O
.	O
</s>
