<s>
The	O
International	B-Protocol
Packet	I-Protocol
Switched	I-Protocol
Service	I-Protocol
(	O
IPSS	O
)	O
was	O
the	O
first	O
international	O
and	O
commercial	O
packet	B-Protocol
switching	I-Protocol
network	O
.	O
</s>
<s>
It	O
was	O
created	O
in	O
1978	O
by	O
a	O
collaboration	O
between	O
Britain	O
's	O
Post	O
Office	O
Telecommunications	O
,	O
and	O
the	O
United	O
States	O
 '	O
Western	O
Union	O
International	O
and	O
Tymnet	B-Application
.	O
</s>
<s>
Companies	O
and	O
individual	O
users	O
could	O
connect	O
in	O
to	O
the	O
network	O
,	O
via	O
a	O
PSS	O
(	O
Packet	B-Protocol
Switch	I-Protocol
Stream	I-Protocol
)	O
modem	B-Application
,	O
or	O
an	O
X.25	B-Protocol
PAD	O
(	O
packet	B-Protocol
assembler/disassembler	I-Protocol
)	O
,	O
and	O
a	O
dedicated	O
PSS	O
line	O
,	O
and	O
use	O
it	O
to	O
connect	O
to	O
a	O
variety	O
of	O
online	O
databases	O
and	O
mainframe	O
systems	O
.	O
</s>
<s>
Companies	O
including	O
Dynatech	O
,	O
were	O
providers	O
of	O
Interconnectivity	O
and	O
infrastructure	O
devices	O
including	O
line	O
drivers	O
,	O
modems	B-Application
,	O
self	O
configuring	O
modems	B-Application
,	O
4	O
port	O
,	O
8	O
port	O
and	O
16	O
port	O
PADs	O
,	O
and	O
switches	O
.	O
</s>
<s>
These	O
were	O
physical	O
boxes	O
delivering	O
full	O
implementation	O
of	O
x.25	B-Protocol
,	O
x.28	O
,	O
x.29	O
and	O
x.3	O
protocols	O
with	O
physical	O
connectivity	O
conforming	O
to	O
RS232	O
asynchronous	O
connectivity	O
specification	O
.	O
</s>
<s>
In	O
1988	O
the	O
IPSS	O
directory	O
listed	O
approximately	O
800	O
global	O
sites	O
available	O
for	O
connection	O
via	O
X.25	B-Protocol
.	O
</s>
<s>
The	O
network	O
later	O
adopted	O
TCP/IP	B-Protocol
and	O
provided	O
infrastructure	O
for	O
the	O
early	O
Internet	O
.	O
</s>
