<s>
A	O
long-running	O
debate	O
in	O
computer	B-General_Concept
science	I-General_Concept
known	O
as	O
the	O
Protocol	B-Protocol
Wars	I-Protocol
occurred	O
from	O
the	O
1970s	O
to	O
the	O
1990s	O
when	O
engineers	O
,	O
organizations	O
and	O
nations	O
became	O
polarized	O
over	O
the	O
issue	O
of	O
which	O
communication	O
protocol	O
would	O
result	O
in	O
the	O
best	O
and	O
most	O
robust	O
computer	B-Architecture
networks	I-Architecture
.	O
</s>
<s>
This	O
culminated	O
in	O
the	O
Internet	B-Protocol
–	I-Protocol
OSI	I-Protocol
Standards	I-Protocol
War	I-Protocol
in	O
the	O
late	O
1980s	O
and	O
early	O
1990s	O
,	O
which	O
was	O
ultimately	O
"	O
won	O
"	O
by	O
the	O
Internet	B-Protocol
protocol	I-Protocol
suite	I-Protocol
(	O
"	O
TCP/IP	B-Protocol
"	O
)	O
by	O
the	O
mid-1990s	O
and	O
has	O
since	O
resulted	O
in	O
most	O
other	O
protocols	O
disappearing	O
.	O
</s>
<s>
The	O
pioneers	O
of	O
packet	B-Protocol
switching	I-Protocol
technology	O
built	O
computer	B-Architecture
networks	I-Architecture
to	O
research	O
data	O
communications	O
in	O
the	O
early	O
1970s	O
.	O
</s>
<s>
As	O
public	O
data	B-Architecture
networks	I-Architecture
emerged	O
in	O
the	O
mid	O
to	O
late	O
1970s	O
,	O
the	O
debate	O
about	O
interface	O
standards	O
was	O
described	O
as	O
a	O
"	O
battle	O
for	O
access	O
standards	O
"	O
.	O
</s>
<s>
An	O
international	O
collaboration	O
between	O
several	O
national	O
postal	O
,	O
telegraph	O
and	O
telephone	O
(	O
"	O
PTT	O
"	O
)	O
providers	O
and	O
commercial	O
operators	O
developed	O
the	O
X.25	B-Protocol
standard	O
in	O
1976	O
,	O
which	O
was	O
adopted	O
on	O
public	O
networks	O
providing	O
global	O
coverage	O
.	O
</s>
<s>
Several	O
proprietary	O
standards	O
also	O
emerged	O
,	O
most	O
notably	O
IBM	O
's	O
Systems	B-Architecture
Network	I-Architecture
Architecture	I-Architecture
.	O
</s>
<s>
The	O
United	O
States	O
Department	O
of	O
Defense	O
developed	O
and	O
tested	O
TCP/IP	B-Protocol
during	O
the	O
1970s	O
in	O
collaboration	O
with	O
universities	O
and	O
researchers	O
in	O
the	O
United	O
States	O
,	O
United	O
Kingdom	O
and	O
France	O
.	O
</s>
<s>
IPv4	B-Protocol
was	O
released	O
in	O
1981	O
and	O
the	O
DoD	O
made	O
it	O
standard	O
for	O
all	O
military	O
computer	B-Architecture
networking	I-Architecture
.	O
</s>
<s>
By	O
1984	O
,	O
an	O
international	O
reference	O
model	O
known	O
as	O
the	O
OSI	O
model	O
had	O
been	O
agreed	O
on	O
,	O
with	O
which	O
TCP/IP	B-Protocol
was	O
not	O
compatible	O
.	O
</s>
<s>
Many	O
governments	O
in	O
Europe	O
–	O
particularly	O
France	O
,	O
West	O
Germany	O
,	O
the	O
United	O
Kingdom	O
and	O
the	O
European	O
Economic	O
Community	O
–	O
and	O
also	O
the	O
United	O
States	O
Department	O
of	O
Commerce	O
mandated	O
compliance	O
with	O
the	O
OSI	O
model	O
and	O
the	O
US	O
Department	O
of	O
Defense	O
planned	O
to	O
transition	O
away	O
from	O
TCP/IP	B-Protocol
to	O
OSI	O
.	O
</s>
<s>
Meanwhile	O
,	O
the	O
development	O
of	O
a	O
complete	O
Internet	B-Protocol
protocol	I-Protocol
suite	I-Protocol
by	O
1989	O
,	O
and	O
partnerships	O
with	O
the	O
telecommunication	O
and	O
computer	O
industry	O
to	O
incorporate	O
TCP/IP	B-Protocol
software	O
into	O
various	O
operating	O
systems	O
laid	O
the	O
foundation	O
for	O
the	O
widespread	O
adoption	O
of	O
TCP/IP	B-Protocol
as	O
a	O
comprehensive	O
protocol	B-Protocol
suite	I-Protocol
.	O
</s>
<s>
While	O
OSI	O
developed	O
its	O
networking	O
standards	O
in	O
the	O
late	O
1980s	O
,	O
TCP/IP	B-Protocol
came	O
into	O
widespread	O
use	O
on	O
multi-vendor	O
networks	O
for	O
internetworking	B-Architecture
and	O
as	O
the	O
core	O
component	O
of	O
the	O
emerging	O
Internet	O
.	O
</s>
<s>
Computer	B-General_Concept
science	I-General_Concept
was	O
an	O
emerging	O
discipline	O
in	O
the	O
late	O
1950s	O
that	O
began	O
to	O
consider	O
time-sharing	B-General_Concept
between	O
computer	O
users	O
and	O
,	O
later	O
,	O
the	O
possibility	O
of	O
achieving	O
this	O
over	O
wide	O
area	O
networks	O
.	O
</s>
<s>
In	O
the	O
1960s	O
,	O
Paul	O
Baran	O
in	O
the	O
United	O
States	O
and	O
Donald	O
Davies	O
in	O
the	O
United	O
Kingdom	O
found	O
it	O
hard	O
to	O
convince	O
incumbent	O
telephone	O
companies	O
of	O
the	O
merits	O
of	O
their	O
ideas	O
for	O
the	O
design	O
of	O
computer	O
data	B-Architecture
networks	I-Architecture
.	O
</s>
<s>
Davies	O
conceived	O
of	O
and	O
named	O
the	O
concept	O
of	O
packet	B-Protocol
switching	I-Protocol
in	O
data	O
communication	O
networks	O
in	O
1965	O
.	O
</s>
<s>
He	O
proposed	O
a	O
national	O
commercial	O
data	B-Architecture
network	I-Architecture
in	O
the	O
UK	O
and	O
built	O
the	O
local-area	O
NPL	B-Protocol
network	I-Protocol
to	O
demonstrate	O
and	O
research	O
his	O
ideas	O
.	O
</s>
<s>
One	O
of	O
the	O
first	O
uses	O
of	O
the	O
term	O
'	O
protocol	O
 '	O
in	O
a	O
data-communication	O
context	O
occurs	O
in	O
a	O
1967	O
memorandum	O
entitled	O
A	O
Protocol	O
for	O
Use	O
in	O
the	O
NPL	B-Protocol
Data	I-Protocol
Communications	I-Protocol
Network	I-Protocol
written	O
by	O
two	O
members	O
of	O
Donald	O
Davies	O
 '	O
team	O
,	O
Roger	O
Scantlebury	O
and	O
Keith	O
Bartlett	O
,	O
who	O
were	O
working	O
on	O
protocols	O
for	O
the	O
NPL	B-Protocol
network	I-Protocol
.	O
</s>
<s>
Roberts	O
incorporated	O
Davies	O
 '	O
and	O
Baran	O
's	O
ideas	O
about	O
packet	B-Protocol
switching	I-Protocol
into	O
the	O
ARPANET	O
design	O
,	O
a	O
project	O
established	O
by	O
the	O
Advanced	O
Research	O
Projects	O
Agency	O
(	O
ARPA	O
)	O
of	O
the	O
United	O
States	O
Department	O
of	O
Defense	O
(	O
DoD	O
)	O
to	O
enable	O
resource	B-General_Concept
sharing	I-General_Concept
between	O
remote	O
computers	O
.	O
</s>
<s>
The	O
network	O
was	O
built	O
by	O
Bolt	O
,	O
Beranek	O
,	O
and	O
Newman	O
(	O
BBN	O
)	O
;	O
the	O
team	O
working	O
on	O
the	O
Interface	B-Protocol
Message	I-Protocol
Processor	I-Protocol
(	O
IMP	O
)	O
,	O
which	O
included	O
Bob	O
Kahn	O
,	O
called	O
themselves	O
the	O
"	O
IMP	O
Guys	O
"	O
.	O
</s>
<s>
Like	O
Baran	O
in	O
the	O
mid-1960s	O
,	O
when	O
Roberts	O
approached	O
AT&T	O
in	O
the	O
early	O
1970s	O
about	O
taking	O
over	O
the	O
ARPANET	O
to	O
offer	O
a	O
public	O
packet	B-Protocol
switched	I-Protocol
service	O
,	O
they	O
declined	O
.	O
</s>
<s>
Louis	O
Pouzin	O
faced	O
opposition	O
from	O
France	O
's	O
PTT	O
,	O
but	O
his	O
ideas	O
to	O
facilitate	O
internetworking	B-Architecture
caught	O
the	O
attention	O
of	O
the	O
ARPANET	O
developers	O
in	O
the	O
early	O
1970s	O
.	O
</s>
<s>
PTTs	O
were	O
operating	O
on	O
the	O
basis	O
of	O
circuit	B-Protocol
switching	I-Protocol
,	O
the	O
alternatives	O
to	O
which	O
are	O
message	B-Protocol
switching	I-Protocol
or	O
packet	B-Protocol
switching	I-Protocol
.	O
</s>
<s>
Packet	B-Protocol
switching	I-Protocol
can	O
be	O
based	O
on	O
either	O
a	O
connectionless	B-Protocol
or	O
connection-oriented	B-Protocol
mode	O
,	O
which	O
are	O
completely	O
different	O
approaches	O
to	O
data	O
communications	O
.	O
</s>
<s>
A	O
connectionless	B-Protocol
datagram	B-Protocol
service	I-Protocol
transports	O
packets	O
independently	O
of	O
other	O
packets	O
whereas	O
a	O
connection-oriented	B-Protocol
virtual	B-Protocol
circuit	I-Protocol
transports	O
packets	O
between	O
terminals	O
in	O
sequence	O
.	O
</s>
<s>
Datagram	B-Protocol
services	I-Protocol
include	O
the	O
information	O
needed	O
for	O
looking	O
up	O
the	O
next	O
link	O
in	O
the	O
network	O
in	O
every	O
packet	O
.	O
</s>
<s>
They	O
also	O
generally	O
make	O
routing	O
around	O
problems	O
simpler	O
as	O
only	O
the	O
single	O
routing	O
table	O
needs	O
to	O
be	O
updated	O
,	O
not	O
the	O
routing	O
information	O
for	O
every	O
virtual	B-Protocol
circuit	I-Protocol
.	O
</s>
<s>
This	O
also	O
requires	O
less	O
memory	O
,	O
as	O
only	O
one	O
route	O
needs	O
to	O
be	O
stored	O
for	O
any	O
destination	O
,	O
not	O
one	O
per	O
virtual	B-Protocol
circuit	I-Protocol
.	O
</s>
<s>
In	O
1974	O
,	O
Rémi	O
Després	O
introduced	O
the	O
term	O
"	O
virtual	B-Protocol
circuit	I-Protocol
"	O
to	O
describe	O
the	O
concept	O
that	O
would	O
later	O
be	O
used	O
in	O
X.25	B-Protocol
.	O
</s>
<s>
Virtual	B-Protocol
circuits	I-Protocol
emulate	O
physical	O
circuits	O
,	O
which	O
are	O
well	O
understood	O
in	O
the	O
telecoms	O
industry	O
and	O
mimics	O
the	O
operation	O
of	O
their	O
equipment	O
.	O
</s>
<s>
Another	O
disadvantage	O
is	O
that	O
the	O
virtual	B-Protocol
connection	I-Protocol
may	O
take	O
some	O
time	O
to	O
set	O
up	O
end-to-end	B-Application
,	O
and	O
for	O
small	O
messages	O
,	O
this	O
time	O
may	O
be	O
significant	O
.	O
</s>
<s>
Building	O
on	O
Donald	O
Davies’	O
work	O
simulating	O
datagram	B-Protocol
networks	O
,	O
Louis	O
Pouzin	O
built	O
CYCLADES	O
to	O
research	O
internetworking	B-Architecture
concepts	O
.	O
</s>
<s>
He	O
first	O
demonstrated	O
the	O
network	O
,	O
which	O
used	O
unreliable	B-Protocol
datagrams	B-Protocol
in	O
the	O
packet-switched	B-Protocol
network	I-Protocol
and	O
virtual	B-Protocol
circuits	I-Protocol
for	O
the	O
transport	O
layer	O
,	O
in	O
1973	O
.	O
</s>
<s>
Under	O
the	O
heading	O
"	O
Datagrams	B-Protocol
versus	O
VC	O
's	O
"	O
,	O
Larry	O
Roberts	O
wrote	O
"	O
As	O
part	O
of	O
the	O
continuing	O
evolution	O
of	O
packet	B-Protocol
switching	I-Protocol
,	O
controversial	O
issues	O
are	O
sure	O
to	O
arise.	O
"	O
</s>
<s>
At	O
the	O
National	O
Physical	O
Laboratory	O
in	O
the	O
United	O
Kingdom	O
,	O
Donald	O
Davies	O
 '	O
team	O
also	O
conducted	O
internetworking	B-Architecture
research	O
.	O
</s>
<s>
To	O
explore	O
this	O
dilemma	O
,	O
the	O
NPL	B-Protocol
network	I-Protocol
connected	O
with	O
the	O
European	B-Protocol
Informatics	I-Protocol
Network	I-Protocol
(	O
EIN	O
)	O
by	O
translating	O
between	O
two	O
different	O
host	O
protocols	O
,	O
that	O
is	O
,	O
using	O
a	O
gateway	B-Application
.	O
</s>
<s>
Concurrently	O
,	O
the	O
NPL	O
connection	O
to	O
the	O
UK	O
Experimental	O
Packet	B-Protocol
Switched	I-Protocol
Service	O
used	O
a	O
common	O
host	O
protocol	O
in	O
both	O
networks	O
.	O
</s>
<s>
On	O
the	O
ARPANET	O
,	O
the	O
starting	O
point	O
for	O
connecting	O
a	O
host	O
computer	O
to	O
an	O
Interface	B-Protocol
Message	I-Protocol
Processor	I-Protocol
in	O
1969	O
was	O
the	O
1822	B-Protocol
protocol	I-Protocol
.	O
</s>
<s>
He	O
and	O
other	O
graduate	O
students	O
at	O
UCLA	O
set	O
about	O
designing	O
a	O
host-host	O
protocol	O
known	O
as	O
the	O
Network	B-Protocol
Control	I-Protocol
Program	I-Protocol
.	O
</s>
<s>
The	O
designers	O
of	O
the	O
NCP	O
envisioned	O
a	O
hierarchy	O
of	O
protocols	O
to	O
enable	O
Telnet	B-Protocol
and	O
File	B-Protocol
Transfer	I-Protocol
Protocol	I-Protocol
(	O
FTP	O
)	O
functions	O
across	O
the	O
ARPANET	O
.	O
</s>
<s>
Internetworking	B-Architecture
research	O
in	O
the	O
early	O
1970s	O
by	O
Bob	O
Kahn	O
at	O
ARPA	O
and	O
Vint	O
Cerf	O
at	O
Stanford	O
University	O
led	O
to	O
the	O
formulation	O
of	O
the	O
first	O
version	O
of	O
the	O
Transmission	B-Protocol
Control	I-Protocol
Program	I-Protocol
(	O
TCP	O
)	O
in	O
1974	O
,	O
drawing	O
on	O
concepts	O
from	O
prior	O
American	O
,	O
British	O
and	O
French	O
research	O
.	O
</s>
<s>
A	O
protocol	O
for	O
internetworking	B-Architecture
was	O
also	O
being	O
pursued	O
by	O
the	O
International	B-Protocol
Networking	I-Protocol
Working	I-Protocol
Group	I-Protocol
,	O
consisting	O
of	O
American	O
researchers	O
,	O
members	O
of	O
the	O
French	O
CYCLADES	O
project	O
,	O
and	O
the	O
British	O
team	O
working	O
on	O
the	O
NPL	B-Protocol
network	I-Protocol
and	O
European	B-Protocol
Informatics	I-Protocol
Network	I-Protocol
.	O
</s>
<s>
INWG	O
members	O
Vint	O
Cerf	O
,	O
Alex	O
McKenzie	O
,	O
Roger	O
Scantlebury	O
and	O
Hubert	O
Zimmermann	O
authored	O
an	O
end-to-end	B-Application
protocol	O
that	O
was	O
presented	O
to	O
the	O
CCITT	O
by	O
Derek	O
Barber	O
in	O
1975	O
but	O
was	O
not	O
adopted	O
by	O
the	O
CCITT	O
nor	O
by	O
the	O
ARPANET	O
.	O
</s>
<s>
The	O
fourth	O
biennial	O
Data	O
Communications	O
Symposium	O
later	O
that	O
year	O
included	O
talks	O
from	O
Donald	O
Davies	O
,	O
Louis	O
Pouzin	O
,	O
Derek	O
Barber	O
,	O
and	O
Ira	O
Cotten	O
about	O
the	O
current	O
state	O
of	O
packet-switched	B-Protocol
networking	O
.	O
</s>
<s>
The	O
conference	O
was	O
covered	O
by	O
Computerworld	O
magazine	O
which	O
ran	O
a	O
story	O
on	O
the	O
"	O
battle	O
for	O
access	O
standards	O
"	O
between	O
datagrams	B-Protocol
and	O
virtual	B-Protocol
circuits	I-Protocol
,	O
as	O
well	O
as	O
a	O
piece	O
describing	O
the	O
"	O
lack	O
of	O
standard	O
access	O
interfaces	O
for	O
emerging	O
public	O
packet-switched	B-Protocol
communication	O
networks	O
is	O
creating	O
'	O
some	O
kind	O
of	O
monster	O
 '	O
for	O
users	O
"	O
.	O
</s>
<s>
At	O
the	O
conference	O
,	O
Louis	O
Pouzin	O
said	O
pressure	O
from	O
European	O
PTTs	O
forced	O
the	O
Canadian	O
DATAPAC	B-Protocol
network	O
to	O
change	O
from	O
a	O
datagram	B-Protocol
to	O
virtual	B-Protocol
circuit	I-Protocol
approach	O
,	O
although	O
historians	O
attribute	O
this	O
to	O
IBM	O
's	O
rejection	O
of	O
their	O
request	O
for	O
modification	O
to	O
their	O
proprietary	O
protocol	O
.	O
</s>
<s>
After	O
leaving	O
ARPA	O
in	O
1973	O
to	O
found	O
Telenet	O
,	O
a	O
commercial	O
packet-switched	B-Protocol
network	I-Protocol
in	O
the	O
U.S.	O
,	O
Larry	O
Roberts	O
joined	O
the	O
international	O
effort	O
to	O
standardize	O
a	O
protocol	O
for	O
packet	B-Protocol
switching	I-Protocol
based	O
on	O
virtual	B-Protocol
circuits	I-Protocol
shortly	O
before	O
it	O
was	O
finalized	O
.	O
</s>
<s>
With	O
contributions	O
from	O
the	O
French	O
,	O
British	O
,	O
and	O
Japanese	O
PTTs	O
,	O
including	O
the	O
work	O
of	O
Rémi	O
Després	O
,	O
along	O
with	O
concepts	O
from	O
DATAPAC	B-Protocol
in	O
Canada	O
,	O
and	O
Telenet	O
in	O
the	O
U.S.	O
,	O
the	O
X.25	B-Protocol
standard	O
was	O
agreed	O
by	O
the	O
CCITT	O
in	O
1976	O
.	O
</s>
<s>
Vint	O
Cerf	O
said	O
Roberts	O
turned	O
down	O
his	O
suggestion	O
to	O
use	O
TCP	O
when	O
he	O
built	O
Telenet	O
,	O
saying	O
that	O
people	O
would	O
only	O
buy	O
virtual	B-Protocol
circuits	I-Protocol
and	O
he	O
could	O
not	O
sell	O
datagrams	B-Protocol
.	O
</s>
<s>
The	O
design	O
of	O
the	O
Transmission	B-Protocol
Control	I-Protocol
Program	I-Protocol
incorporated	O
both	O
connection-oriented	B-Protocol
links	I-Protocol
and	O
datagram	B-Protocol
services	I-Protocol
between	O
hosts	O
.	O
</s>
<s>
In	O
version	O
3	O
of	O
TCP	O
,	O
written	O
in	O
1978	O
,	O
the	O
Transmission	B-Protocol
Control	I-Protocol
Program	I-Protocol
was	O
split	O
into	O
two	O
distinct	O
protocols	O
,	O
the	O
Internet	B-Protocol
Protocol	I-Protocol
(	O
IP	B-Protocol
)	O
as	O
connectionless	B-Protocol
layer	O
and	O
the	O
Transmission	B-Protocol
Control	I-Protocol
Protocol	I-Protocol
(	O
TCP	O
)	O
as	O
a	O
reliable	O
connection-oriented	B-Protocol
service	I-Protocol
.	O
</s>
<s>
Originally	O
referred	O
to	O
as	O
IP/TCP	O
,	O
version	B-Protocol
4	I-Protocol
was	O
installed	O
on	O
SATNET	O
in	O
1982	O
and	O
on	O
the	O
ARPANET	O
in	O
January	O
1983	O
after	O
the	O
DoD	O
made	O
it	O
standard	O
for	O
all	O
military	O
computer	B-Architecture
networking	I-Architecture
.	O
</s>
<s>
This	O
resulted	O
in	O
a	O
networking	O
model	O
that	O
became	O
known	O
informally	O
as	O
TCP/IP	B-Protocol
.	O
</s>
<s>
Computer	O
manufacturers	O
developed	O
proprietary	O
protocol	B-Protocol
suites	I-Protocol
such	O
as	O
IBM	O
's	O
Systems	B-Architecture
Network	I-Architecture
Architecture	I-Architecture
(	O
SNA	O
)	O
,	O
Digital	O
Equipment	O
Corporation	O
's	O
DECnet	B-Protocol
,	O
Xerox	O
's	O
Xerox	B-Protocol
Network	I-Protocol
Systems	I-Protocol
(	O
XNS	O
)	O
and	O
Burroughs	O
 '	O
BNA	O
.	O
</s>
<s>
Therefore	O
,	O
proprietary	O
standards	O
,	O
particularly	O
SNA	O
and	O
DECnet	B-Protocol
,	O
as	O
well	O
as	O
some	O
variants	O
of	O
XNS	O
(	O
e.g.	O
,	O
Novell	B-Operating_System
NetWare	I-Operating_System
and	O
Banyan	B-Operating_System
VINES	I-Operating_System
)	O
,	O
were	O
commonly	O
used	O
on	O
private	O
networks	O
,	O
becoming	O
somewhat	O
"	O
de	O
facto	O
"	O
industry	O
standards	O
.	O
</s>
<s>
The	O
UK	O
Coloured	B-Protocol
Book	I-Protocol
protocols	I-Protocol
gained	O
some	O
acceptance	O
internationally	O
as	O
the	O
first	O
complete	O
X.25	B-Protocol
standard	O
.	O
</s>
<s>
The	O
X.25	B-Protocol
standard	O
gained	O
political	O
support	O
in	O
European	O
countries	O
and	O
from	O
the	O
European	O
Economic	O
Community	O
(	O
EEC	O
)	O
.	O
</s>
<s>
For	O
example	O
,	O
the	O
European	B-Protocol
Informatics	I-Protocol
Network	I-Protocol
,	O
which	O
was	O
based	O
on	O
datagrams	B-Protocol
was	O
replaced	O
with	O
Euronet	O
based	O
on	O
X.25	B-Protocol
.	O
</s>
<s>
As	O
a	O
result	O
,	O
the	O
European	O
networking	O
activities	O
did	O
not	O
lead	O
to	O
any	O
strong	O
standards	O
except	O
X.25	B-Protocol
,	O
which	O
became	O
the	O
main	O
European	O
data	O
protocol	O
for	O
fifteen	O
to	O
twenty	O
years	O
.	O
</s>
<s>
The	O
growth	O
of	O
public	O
data	B-Architecture
networks	I-Architecture
based	O
on	O
the	O
X.25	B-Protocol
protocol	I-Protocol
suite	I-Protocol
through	O
the	O
1980s	O
,	O
notably	O
the	O
International	B-Protocol
Packet	I-Protocol
Switched	I-Protocol
Service	I-Protocol
,	O
created	O
a	O
global	O
infrastructure	O
for	O
commercial	O
data	O
transport	O
.	O
</s>
<s>
It	O
was	O
supplemented	O
by	O
the	O
X.75	B-Protocol
standard	O
,	O
which	O
enabled	O
internetworking	B-Architecture
.	O
</s>
<s>
In	O
the	O
US	O
,	O
the	O
National	O
Science	O
Foundation	O
(	O
NSF	O
)	O
,	O
NASA	O
,	O
and	O
the	O
United	O
States	O
Department	O
of	O
Energy	O
(	O
DoE	O
)	O
all	O
built	O
networks	O
variously	O
based	O
on	O
the	O
DoD	B-Protocol
model	I-Protocol
,	O
DECnet	B-Protocol
,	O
and	O
IP	B-Protocol
over	O
X.25	B-Protocol
.	O
</s>
<s>
The	O
early	O
research	O
and	O
development	O
of	O
standards	O
for	O
data	B-Architecture
networks	I-Architecture
and	O
protocols	O
culminated	O
in	O
the	O
Internet	B-Protocol
–	I-Protocol
OSI	I-Protocol
Standards	I-Protocol
War	I-Protocol
in	O
the	O
late	O
1980s	O
and	O
early	O
1990s	O
.	O
</s>
<s>
Engineers	O
,	O
organizations	O
and	O
nations	O
became	O
polarized	O
over	O
the	O
issue	O
of	O
which	O
standard	O
would	O
result	O
in	O
the	O
best	O
and	O
most	O
robust	O
computer	B-Architecture
networks	I-Architecture
.	O
</s>
<s>
The	O
Experimental	O
Packet	B-Protocol
Switched	I-Protocol
Service	O
in	O
the	O
UK	O
in	O
the	O
mid-late	O
1970s	O
identified	O
the	O
need	O
for	O
defining	O
higher-level	O
protocols	O
.	O
</s>
<s>
The	O
DoD	B-Protocol
model	I-Protocol
and	O
other	O
existing	O
protocols	O
,	O
such	O
as	O
X.25	B-Protocol
and	O
SNA	O
,	O
all	O
quickly	O
adopted	O
a	O
layered	O
approach	O
in	O
the	O
late	O
1970s	O
.	O
</s>
<s>
Although	O
the	O
OSI	O
model	O
shifted	O
power	O
away	O
from	O
the	O
PTTs	O
and	O
IBM	O
towards	O
smaller	O
manufacturer	O
and	O
users	O
,	O
the	O
"	O
strategic	O
battle	O
"	O
remained	O
the	O
competition	O
between	O
the	O
PTTs	O
 '	O
X.25	B-Protocol
and	O
proprietary	O
standards	O
,	O
particularly	O
SNA	O
.	O
</s>
<s>
Until	O
the	O
NSF	O
took	O
over	O
in	O
the	O
1980s	O
,	O
TCP/IP	B-Protocol
was	O
not	O
even	O
a	O
candidate	O
for	O
universal	O
adoption	O
.	O
</s>
<s>
The	O
implementation	O
of	O
the	O
Domain	B-Protocol
Name	I-Protocol
System	I-Protocol
in	O
1985	O
and	O
the	O
development	O
of	O
a	O
complete	O
protocol	B-Protocol
suite	I-Protocol
by	O
1989	O
,	O
as	O
outlined	O
in	O
and	O
,	O
laid	O
the	O
foundation	O
for	O
growth	O
of	O
TCP/IP	B-Protocol
as	O
a	O
comprehensive	O
protocol	B-Protocol
suite	I-Protocol
,	O
which	O
became	O
known	O
as	O
the	O
Internet	B-Protocol
protocol	I-Protocol
suite	I-Protocol
.	O
</s>
<s>
Historian	O
Andrew	O
L	O
.	O
Russell	O
wrote	O
that	O
Internet	O
engineers	O
such	O
as	O
Danny	O
Cohen	O
and	O
Jon	O
Postel	O
were	O
accustomed	O
to	O
continual	O
experimentation	O
in	O
a	O
fluid	O
organizational	O
setting	O
through	O
which	O
they	O
developed	O
TCP/IP	B-Protocol
.	O
</s>
<s>
During	O
a	O
dispute	O
within	O
the	O
Internet	O
community	O
,	O
Vint	O
Cerf	O
performed	O
a	O
striptease	O
in	O
a	O
three-piece	O
suit	O
at	O
the	O
1992	O
Internet	O
Engineering	O
Task	O
Force	O
(	O
IETF	O
)	O
meeting	O
,	O
revealing	O
a	O
T-shirt	O
emblazoned	O
with	O
"	O
IP	B-Protocol
on	O
Everything	O
"	O
;	O
according	O
to	O
Cerf	O
,	O
his	O
intention	O
was	O
to	O
reiterate	O
that	O
a	O
goal	O
of	O
the	O
Internet	O
Architecture	O
Board	O
was	O
to	O
run	O
IP	B-Protocol
on	O
every	O
underlying	O
transmission	O
medium	O
.	O
</s>
<s>
They	O
advocated	O
for	O
a	O
pluralistic	O
model	O
of	O
internetworking	B-Architecture
where	O
many	O
different	O
network	O
architectures	O
could	O
be	O
joined	O
into	O
a	O
network	O
of	O
networks	O
.	O
</s>
<s>
The	O
model	O
defined	O
seven	O
layers	O
of	O
computer	B-Architecture
communications	I-Architecture
,	O
from	O
physical	O
media	O
in	O
layer	O
1	O
to	O
applications	O
in	O
layer	O
7	O
,	O
which	O
was	O
more	O
layers	O
than	O
the	O
network	O
engineering	O
community	O
had	O
anticipated	O
.	O
</s>
<s>
Although	O
some	O
sources	O
say	O
this	O
was	O
an	O
acknowledgement	O
that	O
the	O
four	O
layers	O
of	O
the	O
Internet	B-Protocol
Protocol	I-Protocol
Suite	I-Protocol
were	O
inadequate	O
.	O
</s>
<s>
The	O
OSI	O
model	O
allowed	O
what	O
some	O
saw	O
as	O
too	O
many	O
transport	O
protocols	O
(	O
five	O
compared	O
with	O
two	O
for	O
TCP/IP	B-Protocol
)	O
.	O
</s>
<s>
Furthermore	O
,	O
OSI	O
allowed	O
for	O
both	O
the	O
datagram	B-Protocol
and	O
the	O
virtual	B-Protocol
circuit	I-Protocol
approach	O
at	O
the	O
network	O
layer	O
,	O
which	O
are	O
non-interoperable	O
options	O
.	O
</s>
<s>
Beginning	O
in	O
the	O
early	O
1980s	O
,	O
ARPA	O
pursued	O
commercial	O
partnerships	O
with	O
the	O
telecommunication	O
and	O
computer	O
industry	O
which	O
enabled	O
the	O
adoption	O
of	O
TCP/IP	B-Protocol
.	O
</s>
<s>
In	O
Europe	O
,	O
CERN	O
purchased	O
UNIX	B-Application
machines	O
with	O
TCP/IP	B-Protocol
for	O
their	O
intranet	O
between	O
1984	O
and	O
1988	O
.	O
</s>
<s>
Nonetheless	O
,	O
Paul	O
Bryant	O
,	O
the	O
UK	O
representative	O
on	O
the	O
EARN	O
Board	O
of	O
Directors	O
,	O
said	O
"	O
By	O
the	O
time	O
JNT	O
[	O
the	O
UK	O
academic	O
network	O
JANET ]	O
came	O
along	O
[	O
in	O
1984 ]	O
we	O
could	O
demonstrate	O
X25	O
...	O
and	O
we	O
firmly	O
believed	O
that	O
BT	O
[	O
British	O
Telecom ]	O
would	O
provide	O
us	O
with	O
the	O
network	B-Architecture
infrastructure	I-Architecture
and	O
we	O
could	O
do	O
away	O
with	O
leased	O
lines	O
and	O
experimental	O
work	O
.	O
</s>
<s>
JANET	O
was	O
a	O
free	O
X.25-based	O
network	O
for	O
academic	O
use	O
,	O
not	O
research	O
;	O
experiments	O
and	O
other	O
protocols	O
were	O
forbidden	O
.	O
</s>
<s>
The	O
NSFNET	O
initiated	O
operations	O
in	O
1986	O
using	O
TCP/IP	B-Protocol
but	O
,	O
two	O
years	O
later	O
,	O
the	O
US	O
Department	O
of	O
Commerce	O
mandated	O
compliance	O
with	O
the	O
OSI	O
model	O
and	O
the	O
Department	O
of	O
Defense	O
planned	O
to	O
transition	O
away	O
from	O
TCP/IP	B-Protocol
to	O
OSI	O
.	O
</s>
<s>
They	O
founded	O
RARE	O
and	O
associated	O
national	O
network	O
operators	O
(	O
such	O
as	O
DFN	O
,	O
SURFnet	O
,	O
SWITCH	O
)	O
to	O
promote	O
OSI	B-Protocol
protocols	I-Protocol
,	O
and	O
restricted	O
funding	O
for	O
non-OSI	O
compliant	O
protocols	O
.	O
</s>
<s>
However	O
,	O
in	O
1988	O
,	O
EUnet	O
,	O
the	O
European	O
UNIX	B-Application
Network	O
,	O
announced	O
its	O
conversion	O
to	O
Internet	B-Protocol
technology	I-Protocol
.	O
</s>
<s>
TCP/IP	B-Protocol
by	O
comparison	O
was	O
not	O
an	O
official	O
standard	O
(	O
it	O
was	O
defined	O
in	O
unofficial	O
RFCs	O
)	O
but	O
UNIX	B-Application
workstations	O
with	O
both	O
Ethernet	O
and	O
TCP/IP	B-Protocol
included	O
had	O
been	O
available	O
since	O
1983	O
.	O
</s>
<s>
By	O
the	O
beginning	O
of	O
the	O
1990s	O
,	O
some	O
smaller	O
European	O
countries	O
had	O
adopted	O
TCP/IP	B-Protocol
.	O
</s>
<s>
In	O
February	O
1990	O
,	O
RARE	O
stated	O
"	O
without	O
putting	O
into	O
question	O
its	O
OSI	O
policy	O
,	O
 [ RARE ] 	O
recognizes	O
the	O
TCP/IP	B-Protocol
family	O
of	O
protocols	O
as	O
an	O
open	O
multivendor	O
suite	O
,	O
well	O
adapted	O
to	O
scientific	O
and	O
technical	O
applications.	O
"	O
</s>
<s>
In	O
the	O
same	O
month	O
,	O
CERN	O
established	O
a	O
transatlantic	O
TCP/IP	B-Protocol
link	O
with	O
Cornell	O
University	O
in	O
the	O
United	O
States	O
.	O
</s>
<s>
Conversely	O
,	O
starting	O
in	O
August	O
1990	O
,	O
the	O
NSFNET	O
backbone	B-General_Concept
supported	O
the	O
OSI	B-Protocol
Connectionless	I-Protocol
Network	I-Protocol
Protocol	I-Protocol
(	O
CLNP	B-Protocol
)	O
in	O
addition	O
to	O
TCP/IP	B-Protocol
.	O
</s>
<s>
CLNP	B-Protocol
was	O
demonstrated	O
in	O
production	O
on	O
NSFNET	O
in	O
April	O
1991	O
,	O
and	O
OSI	O
demonstrations	O
,	O
including	O
interconnections	O
between	O
U.S.	O
and	O
European	O
sites	O
,	O
were	O
planned	O
at	O
the	O
InterOp	O
'	O
91	O
conference	O
in	O
October	O
that	O
year	O
.	O
</s>
<s>
At	O
the	O
Rutherford	O
Appleton	O
Laboratory	O
(	O
RAL	O
)	O
in	O
the	O
United	O
Kingdom	O
in	O
January	O
1991	O
,	O
DECnet	B-Protocol
represented	O
75%	O
of	O
traffic	O
,	O
attributed	O
to	O
Ethernet	O
between	O
VAXs	O
.	O
</s>
<s>
IP	B-Protocol
was	O
the	O
second	O
most	O
popular	O
set	O
of	O
protocols	O
with	O
20%	O
of	O
traffic	O
,	O
attributed	O
to	O
UNIX	B-Application
machines	O
for	O
which	O
"	O
IP	B-Protocol
is	O
the	O
natural	O
choice	O
"	O
.	O
</s>
<s>
In	O
the	O
Central	O
Computing	O
Department	O
Newsletter	O
,	O
Paul	O
Bryant	O
,	O
Head	O
of	O
Communications	O
and	O
Small	O
Systems	O
at	O
RAL	O
,	O
wrote	O
"	O
Experience	O
has	O
shown	O
that	O
IP	B-Protocol
systems	O
are	O
very	O
easy	O
to	O
mount	O
and	O
use	O
,	O
in	O
contrast	O
to	O
such	O
systems	O
as	O
SNA	O
and	O
to	O
a	O
lesser	O
extent	O
X.25	B-Protocol
and	O
Coloured	B-Protocol
Books	I-Protocol
where	O
the	O
systems	O
are	O
rather	O
more	O
complex.	O
"	O
</s>
<s>
The	O
author	O
continued	O
"	O
The	O
principal	O
network	O
within	O
the	O
USA	O
for	O
academic	O
traffic	O
is	O
now	O
based	O
on	O
IP	B-Protocol
.	O
</s>
<s>
IP	B-Protocol
has	O
recently	O
become	O
popular	O
within	O
Europe	O
for	O
inter-site	O
traffic	O
and	O
there	O
are	O
moves	O
to	O
try	O
and	O
coordinate	O
this	O
activity	O
.	O
</s>
<s>
This	O
can	O
be	O
achieved	O
by	O
gatewaying	O
Coloured	B-Protocol
Book	I-Protocol
protocols	I-Protocol
to	O
IP	B-Protocol
or	O
by	O
allowing	O
IP	B-Protocol
to	O
penetrate	O
the	O
UK	O
.	O
</s>
<s>
Gateways	B-Application
are	O
well	O
known	O
to	O
be	O
a	O
cause	O
of	O
loss	O
of	O
quality	O
and	O
frustration	O
.	O
</s>
<s>
Allowing	O
IP	B-Protocol
to	O
penetrate	O
may	O
well	O
upset	O
the	O
networking	O
strategy	O
of	O
the	O
UK.	O
"	O
</s>
<s>
At	O
CERN	O
,	O
François	O
Flückiger	O
reflected	O
"	O
The	O
technology	O
is	O
simple	O
,	O
efficient	O
,	O
is	O
integrated	O
into	O
UNIX-type	O
operating	O
systems	O
and	O
costs	O
nothing	O
for	O
the	O
users’	O
computers	O
.	O
</s>
<s>
Beginning	O
in	O
March	O
1991	O
,	O
the	O
JANET	O
IP	B-Protocol
Service	O
(	O
JIPS	O
)	O
was	O
set	O
up	O
as	O
a	O
pilot	O
project	O
to	O
host	O
IP	B-Protocol
traffic	O
on	O
the	O
existing	O
network	O
.	O
</s>
<s>
Within	O
eight	O
months	O
,	O
the	O
IP	B-Protocol
traffic	O
had	O
exceeded	O
the	O
levels	O
of	O
X.25	B-Protocol
traffic	O
,	O
and	O
the	O
IP	B-Protocol
support	O
became	O
official	O
in	O
November	O
.	O
</s>
<s>
Also	O
in	O
1991	O
,	O
Dai	O
Davies	O
introduced	O
Internet	B-Protocol
technology	I-Protocol
over	O
X.25	B-Protocol
into	O
the	O
pan-European	O
NREN	O
,	O
EuropaNet	B-Protocol
,	O
although	O
he	O
experienced	O
personal	O
opposition	O
to	O
this	O
approach	O
.	O
</s>
<s>
The	O
European	O
Academic	O
and	O
Research	O
Network	O
(	O
EARN	O
)	O
and	O
RARE	O
adopted	O
IP	B-Protocol
around	O
the	O
same	O
time	O
,	O
and	O
the	O
European	O
Internet	B-General_Concept
backbone	I-General_Concept
EBONE	O
became	O
operational	O
in	O
1992	O
.	O
</s>
<s>
OSI	O
usage	O
on	O
the	O
NSFNET	O
remained	O
low	O
when	O
compared	O
to	O
TCP/IP	B-Protocol
.	O
</s>
<s>
There	O
was	O
some	O
talk	O
of	O
moving	O
JANET	O
to	O
OSI	B-Protocol
protocols	I-Protocol
in	O
the	O
1990s	O
,	O
but	O
this	O
never	O
happened	O
.	O
</s>
<s>
The	O
X.25	B-Protocol
service	O
was	O
closed	O
in	O
August	O
1997	O
.	O
</s>
<s>
The	O
U.S.	O
National	O
Institute	O
for	O
Standards	O
and	O
Technology	O
proposed	O
in	O
1994	O
that	O
GOSIP	O
should	O
incorporate	O
TCP/IP	B-Protocol
and	O
drop	O
the	O
requirement	O
for	O
compliance	O
with	O
OSI	O
,	O
which	O
was	O
adopted	O
into	O
Federal	O
Information	O
Processing	O
Standards	O
the	O
following	O
year	O
.	O
</s>
<s>
Subsequently	O
,	O
the	O
Internet	B-General_Concept
backbone	I-General_Concept
was	O
provided	O
by	O
commercial	O
Internet	O
service	O
providers	O
and	O
Internet	O
connectivity	O
became	O
ubiquitous	O
.	O
</s>
<s>
As	O
the	O
Internet	O
evolved	O
and	O
expanded	O
exponentially	O
,	O
an	O
enhanced	O
protocol	O
was	O
developed	O
,	O
IPv6	B-Protocol
,	O
to	O
address	O
IPv4	B-Protocol
address	I-Protocol
exhaustion	I-Protocol
.	O
</s>
<s>
In	O
the	O
21st	O
century	O
,	O
the	B-Operating_System
Internet	I-Operating_System
of	I-Operating_System
things	I-Operating_System
is	O
leading	O
to	O
the	O
connection	O
of	O
new	O
types	O
of	O
devices	O
to	O
the	O
Internet	O
,	O
bringing	O
reality	O
to	O
Cerf	O
's	O
vision	O
of	O
"	O
IP	B-Protocol
on	O
Everything	O
"	O
.	O
</s>
<s>
Nonetheless	O
,	O
issues	O
with	O
IPv6	B-Protocol
remain	O
and	O
alternatives	O
have	O
been	O
proposed	O
such	O
as	O
Recursive	O
Network	O
Architecture	O
,	O
and	O
Recursive	B-Architecture
InterNetwork	I-Architecture
Architecture	I-Architecture
.	O
</s>
<s>
The	O
seven-layer	O
OSI	O
model	O
is	O
still	O
used	O
as	O
a	O
reference	O
for	O
teaching	O
and	O
documentation	O
;	O
however	O
,	O
the	O
OSI	B-Protocol
protocols	I-Protocol
originally	O
conceived	O
for	O
the	O
model	O
did	O
not	O
gain	O
popularity	O
.	O
</s>
<s>
Some	O
engineers	O
argue	O
the	O
OSI	O
reference	O
model	O
is	O
still	O
relevant	O
to	O
cloud	B-Architecture
computing	I-Architecture
.	O
</s>
<s>
Other	O
standards	O
such	O
as	O
X.25	B-Protocol
and	O
SNA	O
remain	O
niche	O
players	O
.	O
</s>
<s>
His	O
work	O
shifts	O
scholarly	O
and	O
popular	O
understanding	O
about	O
the	O
origins	O
of	O
the	O
Internet	O
and	O
contemporary	O
work	O
in	O
Europe	O
that	O
both	O
competed	O
and	O
cooperated	O
with	O
the	O
push	O
for	O
TCP/IP	B-Protocol
.	O
</s>
