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␈↓ ↓N␈↓ε␈↓ α¬Communicating by DIALNET                    ␈↓ π∞␈↓Computer␈α∃networks␈α∃already␈α∃exist␈α∃providing
␈↓ ↓N␈↓ε␈↓ α&␈↓αJohn McCarthy and Les Earnest               ␈↓ π∞␈↓such␈α
services,␈α
the␈α
most␈α
famous␈α
being␈α
the␈αU.S.
␈↓ ↓N␈↓α␈↓ α>␈↓↓Computer Science Department                 ␈↓ π∞␈↓Defense␈α_Department's␈α_ARPAnet.␈α↔ However,
␈↓ ↓N␈↓↓␈↓ βStanford University                         ␈↓ π∞␈↓these␈α∨networks␈α∨require␈α expensive␈α∨special
                                            ␈↓ π∞␈↓communication␈α$computers,␈α%use␈α$expensive
␈↓ ↓N␈↓␈↓↓Dialnet␈↓␈α
is␈α
a␈α∞project␈α
at␈α
Stanford␈α∞University␈α
to     ␈↓ π∞␈↓special␈α≡communication␈α≡lines,␈α≡and␈α≥involve
␈↓ ↓N␈↓give␈α↔users␈α_of␈α↔a␈α↔time-shared␈α_computer␈α↔the          ␈↓ π∞␈↓substantial␈α∂politics␈α∂and/or␈α∂expense␈α∂in␈α∞joining
␈↓ ↓N␈↓ability␈α!to␈α!communicate␈α!with␈α"any␈α!other            ␈↓ π∞␈↓the␈α∩network.␈α∩ There␈α∩is␈α∩also␈α∩much␈α⊃telephone
␈↓ ↓N␈↓computer in the world by ordinary telephone.␈↓ π∞␈↓communication␈α↔between␈α⊗pairs␈α↔of␈α⊗computers
                                            ␈↓ π∞␈↓that␈α⊗have␈α⊗made␈α⊗special␈α⊗arrangements␈α⊗with
␈↓ ↓N␈↓Three␈α∀main␈α∀kinds␈α∀of␈α∀services␈α∀are␈α∀planned.         ␈↓ π∞␈↓each␈α∀other.␈α∀ ␈↓↓Dialnet␈↓␈α∀communication,␈α∀on␈α∪the
␈↓ ↓N␈↓First,␈α⊃a␈α⊃user␈α∩of␈α⊃one␈α⊃computer,␈α⊃sitting␈α∩at␈α⊃his       ␈↓ π∞␈↓other␈α∪hand,␈α∀can␈α∪be␈α∀done␈α∪by␈α∀any␈α∪computer
␈↓ ↓N␈↓terminal,␈α
can␈αtype␈α
a␈α
message␈αand␈α
have␈α
it␈αsent       ␈↓ π∞␈↓equipped␈α⊃with␈α⊃a␈α⊃dialer␈α⊃and␈α∩modem␈α⊃(costing
␈↓ ↓N␈↓to␈αa␈αuser␈αof␈αanother␈αcomputer␈αor␈αeven␈αto␈αa␈α
list       ␈↓ π∞␈↓less␈α∩than␈α⊃$1,000)␈α∩and␈α⊃which␈α∩implements␈α⊃the
␈↓ ↓N␈↓of␈α
users␈α
of␈αmany␈α
computers.␈α
 He␈α
may␈αhave␈α
the        ␈↓ π∞␈↓␈↓↓Dialnet␈↓␈αprotocols.␈α
 Once␈αthis␈α
is␈αdone,␈α
its␈αusers
␈↓ ↓N␈↓message␈α∂sent␈α∞right␈α∂away␈α∞or␈α∂ask␈α∂his␈α∞computer        ␈↓ π∞␈↓can␈α~communicate␈α≠with␈α~any␈α≠other␈α~␈↓↓Dialnet␈↓
␈↓ ↓N␈↓to␈α∂wait␈α∞for␈α∂low␈α∞night␈α∂telephone␈α∂rates.␈α∞ When       ␈↓ π∞␈↓computer␈α∀in␈α∀the␈α∀world␈α∀just␈α∀as␈α∃anyone␈α∀can
␈↓ ↓N␈↓the␈α!intended␈α!recipient␈α!next␈α!activates␈α a          ␈↓ π∞␈↓telephone␈α⊃anyone␈α⊂else␈α⊃in␈α⊂the␈α⊃world.␈α⊂ Present
␈↓ ↓N␈↓terminal␈α
on␈α
his␈α
own␈α
computer,␈α
he␈α
is␈α
told␈α
about      ␈↓ π∞␈↓telephone␈αrates␈αmake␈αtransmission␈αof␈αmessages
␈↓ ↓N␈↓the␈αmessage␈αand␈αcan␈αread␈αit␈αwhen␈αconvenient.       ␈↓ π∞␈↓and␈α⊃≡les␈α⊃quite␈α⊂economical,␈α⊃but␈α⊃long␈α⊂distance
␈↓ ↓N␈↓Second,␈α∩a␈α∩user␈α∩of␈α∩one␈α∩computer␈α∩can␈α∩ask␈α⊃to           ␈↓ π∞␈↓␈↓↓virtual␈α∃terminals␈↓␈α∃will␈α∀be␈α∃too␈α∃expensive␈α∀for
␈↓ ↓N␈↓have␈α⊃a␈α∩≡le␈α⊃of␈α∩information␈α⊃transferred␈α∩to␈α⊃or        ␈↓ π∞␈↓routine␈α∪use.␈α∀ Special␈α∪networks␈α∪can␈α∀be␈α∪more
␈↓ ↓N␈↓from␈α⊂another␈α⊂computer.␈α⊂ This␈α⊂speeds␈α⊂up␈α∂the        ␈↓ π∞␈↓economical␈α
for␈α
that,␈α
because␈α
they␈α
can␈α
conduct
␈↓ ↓N␈↓exchange␈α
of␈α
reports␈αof␈α
all␈α
kinds,␈α
data␈α≡les,␈α
and    ␈↓ π∞␈↓many dialogs over the same telephone lines.
␈↓ ↓N␈↓computer␈α∃programs.␈α⊗ Third,␈α∃a␈α∃user␈α⊗of␈α∃one
␈↓ ↓N␈↓computer␈α≥can␈α≤ask␈α≥to␈α≤have␈α≥his␈α≤terminal             ␈↓ π∞␈↓Work␈α∃on␈α∃this␈α⊗project␈α∃began␈α∃in␈α⊗July␈α∃1977
␈↓ ↓N␈↓"connected"␈α∩as␈α⊃a␈α∩␈↓↓virtual␈α⊃terminal␈↓␈α∩to␈α⊃another      ␈↓ π∞␈↓under␈α⊗sponsorship␈α∃of␈α⊗the␈α⊗National␈α∃Science
␈↓ ↓N␈↓computer␈α∞so␈α∞that␈α∞he␈α∞can␈α∞use␈α∞its␈α∂services.␈α∞ All      ␈↓ π∞␈↓Foundation.␈α≠ Preliminary␈α≤Dialnet␈α≠protocols
␈↓ ↓N␈↓these␈αparticular␈αservices␈αare␈αrealized␈αby␈αletting ␈↓ π∞␈↓will␈α⊃be␈α∩available␈α⊃early␈α⊃in␈α∩1978␈α⊃and␈α∩a␈α⊃more
␈↓ ↓N␈↓a␈α⊗program␈α⊗in␈α⊗one␈α⊗computer␈α↔"telephone"␈α⊗a           ␈↓ π∞␈↓polished␈α∪version␈α∪is␈α∪targeted␈α∪for␈α∪the␈α∪end␈α∩of
␈↓ ↓N␈↓program␈α3in␈α3another␈α4computer␈α3and                 ␈↓ π∞␈↓1978.␈α∪ People␈α∪interested␈α∪in␈α∪implementing␈α∪or
␈↓ ↓N␈↓communicate␈α∪with␈α∪it.␈α∪ Of␈α∪course,␈α∪the␈α∪called       ␈↓ π∞␈↓in∨uencing␈α≤the␈α≤protocols␈α≤should␈α≤write␈α≠to
␈↓ ↓N␈↓computer␈αcan␈αrefuse␈αto␈αperform␈αany␈αservice␈αits     ␈↓ π∞␈↓␈↓↓Dialnet␈↓,␈α!Arti≡cial␈α!Intelligence␈α!Laboratory,
␈↓ ↓N␈↓owners haven't authorized.                  ␈↓ π∞␈↓Stanford, CA 94305.

␈↓ ↓N␈↓In␈α∀order␈α∀to␈α∀provide␈α∀␈↓↓Dialnet␈↓␈α∀services␈α∃to␈α∀its
␈↓ ↓N␈↓users,␈α
a␈α
computer␈α
needs␈α
a␈αcomputer-controlled
␈↓ ↓N␈↓telephone␈α
dialer␈α∞and␈α
a␈α∞device␈α
called␈α∞a␈α
␈↓↓modem␈↓
␈↓ ↓N␈↓for␈α⊗translating␈α⊗information␈α∃to␈α⊗and␈α⊗from␈α∃a
␈↓ ↓N␈↓form␈αsuitable␈αfor␈αtelephone␈αtransmission.␈α The
␈↓ ↓N␈↓computer␈α
must␈α
also␈α
have␈α
programs␈α
to␈α
interpret
␈↓ ↓N␈↓control␈α∀messages␈α∀from␈α∀other␈α∀computers␈α∪and
␈↓ ↓N␈↓initiate␈α∪control␈α∪messages␈α∪of␈α∪its␈α∀own.␈α∪ These
␈↓ ↓N␈↓messages␈α→must␈α→conform␈α→to␈α→a␈α→standard␈α_or
␈↓ ↓N␈↓␈↓↓protocol␈↓␈α∞so␈α∞that␈α∞all␈α∞computers␈α∞will␈α
understand
␈↓ ↓N␈↓how␈α
to␈α
handle␈α
them.␈α
 The␈α
Stanford␈α
University
␈↓ ↓N␈↓project␈α∪will␈α∩develop␈α∪and␈α∩test␈α∪such␈α∩standard
␈↓ ↓N␈↓␈↓↓protocols␈↓.