<s>
The	O
Open	B-Protocol
Settlement	I-Protocol
Protocol	I-Protocol
(	O
OSP	O
)	O
is	O
a	O
client/server	O
protocol	O
used	O
by	O
Internet	O
service	O
providers	O
to	O
exchange	O
authorization	O
,	O
accounting	O
,	O
and	O
usage	O
information	O
to	O
support	O
IP	B-Application
telephony	I-Application
.	O
</s>
<s>
Open	B-Protocol
Settlement	I-Protocol
Protocol	I-Protocol
is	O
implemented	O
in	O
voice	O
telephony	O
gateways	O
such	O
as	O
softswitches	O
,	O
H.323	B-Protocol
multimedia	O
conferencing	O
gateways	O
,	O
and	O
Session	B-Application
Initiation	I-Application
Protocol	I-Application
(	O
SIP	O
)	O
proxies	O
.	O
</s>
<s>
A	O
press	O
release	O
of	O
September	O
2	O
,	O
1998	O
,	O
announced	O
that	O
the	O
industry	O
leaders	O
3Com	O
Corporation	O
,	O
Cisco	O
,	O
GRIC	O
Communications	O
,	O
iPass	O
Inc.	O
,	O
and	O
TransNexus	O
had	O
"	O
teamed	O
up	O
to	O
promote	O
inter-domain	B-Architecture
authentication	O
,	O
authorization	O
and	O
accounting	O
standards	O
for	O
IP	B-Application
telephony	I-Application
through	O
the	O
Open	B-Protocol
Settlement	I-Protocol
Protocol	I-Protocol
(	O
OSP	O
)	O
"	O
.	O
</s>
<s>
The	O
Open	B-Protocol
Settlement	I-Protocol
Protocol	I-Protocol
is	O
being	O
developed	O
under	O
the	O
authority	O
of	O
the	O
European	O
Telecommunications	O
Standards	O
Institute	O
's	O
ETSI	O
project	O
TIPHON	O
.	O
</s>
<s>
 [ to ] 	O
ensure	O
that	O
users	O
connected	O
to	O
IP	O
based	O
networks	O
can	O
communicate	O
with	O
users	O
in	O
Switched	O
Circuit	O
Networks	O
(	O
such	O
as	O
PSTN/ISDN	O
and	O
GSM	O
)	O
,	O
and	O
vice	O
versa.	O
"	O
</s>
<s>
One	O
of	O
the	O
benefits	O
of	O
the	O
new	O
Open	B-Protocol
Settlement	I-Protocol
Protocol	I-Protocol
is	O
:	O
"	O
flexible	O
and	O
feature-rich	B-Architecture
information	O
exchange	O
via	O
the	O
Extensible	B-Protocol
Markup	I-Protocol
Language	I-Protocol
(	O
XML	B-Protocol
)	O
"	O
.	O
</s>
<s>
The	O
message	O
system	O
defined	O
in	O
the	O
protocol	O
architecture	O
uses	O
HTTP	B-Protocol
to	O
communicate	O
the	O
principal	O
message	O
content	O
;	O
this	O
includes	O
a	O
MIME	B-Protocol
header	O
together	O
with	O
the	O
XML	B-Protocol
document	I-Protocol
in	O
a	O
<Message>	O
.	O
</s>
<s>
Open	B-Protocol
Settlement	I-Protocol
Protocol	I-Protocol
standard	O
specification	O
may	O
be	O
found	O
in	O
the	O
document	O
ETSI	O
Technical	O
Specification	O
101	O
321	O
:	O
Telecommunications	O
and	O
Internet	O
Protocol	O
Harmonization	O
Over	O
Networks	O
(	O
TIPHON	O
)	O
Release	O
4	O
:	O
Open	B-Protocol
Settlement	I-Protocol
Protocol	I-Protocol
for	O
Inter-domain	B-Architecture
pricing	O
,	O
authorisation	O
,	O
and	O
usage	O
exchange	O
.	O
</s>
<s>
"	O
This	O
document	O
specifies	O
a	O
set	O
of	O
protocols	O
and	O
associated	O
profiles	O
to	O
permit	O
the	O
exchange	O
of	O
inter-domain	B-Architecture
pricing	O
,	O
authorisation	O
,	O
and	O
settlement	O
information	O
between	O
internet	B-Application
telephony	I-Application
operators	O
.	O
</s>
<s>
It	O
outlines	O
the	O
overall	O
XML	B-Protocol
document	I-Protocol
structure	O
,	O
lists	O
the	O
individual	O
XML	B-Protocol
elements	O
,	O
and	O
describes	O
how	O
those	O
elements	O
are	O
combined	O
into	O
exchanges.	O
"	O
</s>
<s>
XML	B-Protocol
element	O
and	O
attribute	O
declarations	O
in	O
this	O
section	O
define	O
the	O
provisional	O
DTD	B-Language
for	O
the	O
Open	B-Protocol
Settlement	I-Protocol
Protocol	I-Protocol
.	O
</s>
<s>
The	O
OSP	O
Toolkit	O
is	O
a	O
complete	O
development	O
kit	O
for	O
software	O
developers	O
who	O
want	O
to	O
implement	O
the	O
client	O
side	O
of	O
the	O
European	O
Telecommunication	O
Standards	O
Institute	O
's	O
(	O
ETSI	O
)	O
OSP	O
standard	O
for	O
secure	O
VoIP	B-Application
peering	O
.	O
</s>
