<s>
OpenSky	O
was	O
a	O
service	O
provided	O
by	O
Gizmo5	B-Application
,	O
which	O
is	O
now	O
out	O
of	O
business	O
,	O
to	O
enable	O
communication	O
between	O
users	O
of	O
SIP	B-Application
(	O
Internet	O
standard	O
RFC	O
3261	O
)	O
and	O
users	O
of	O
Skype	B-Application
(	O
which	O
uses	O
a	O
proprietary	O
protocol	O
)	O
.	O
</s>
<s>
Early	O
solutions	O
to	O
communication	O
between	O
the	O
two	O
classes	O
of	O
user	O
typically	O
required	O
installation	B-Application
of	O
a	O
gateway	B-Application
.	O
</s>
<s>
OpenSky	O
–	O
the	O
first	O
freely	O
available	O
hosted	O
SIP	B-Application
to	O
Skype	B-Application
gateway	B-Application
service	O
–	O
commenced	O
on	O
9	O
February	O
2009	O
.	O
</s>
<s>
In	O
March	O
2009	O
Skype	B-Application
announced	O
a	O
beta	O
of	O
Skype	B-Application
For	O
SIP	B-Application
,	O
a	O
comparable	O
service	O
for	O
business	O
users	O
.	O
</s>
<s>
On	O
30	O
July	O
2009	O
Digium	O
,	O
Inc	O
.	O
announced	O
the	O
opening	O
of	O
Skype	B-Application
for	O
Asterisk	O
Public	O
Beta	O
(	O
prior	O
to	O
the	O
open	O
phase	O
,	O
from	O
25	O
September	O
2008	O
,	O
Skype	B-Application
for	O
Asterisk	O
Beta	O
was	O
apparently	O
non-open	O
)	O
.	O
</s>
