"A Brief History of the Internet" - читать интересную книгу автора (Sterling Bruce)

Bruce Sterling

A Brief History of the Internet


Some thirty years ago, the RAND Corporation, America's foremost Cold War think-
tank, faced a strange strategic problem. How could the US authorities
successfully communicate after a nuclear war?

Postnuclear America would need a command-and-control network, linked from city
to city, state to state, base to base. But no matter how thoroughly that network
was armored or protected, its switches and wiring would always be vulnerable to
the impact of atomic bombs. A nuclear attack would reduce any conceivable
network to tatters.

And how would the network itself be commanded and controlled? Any central
authority, any network central citadel, would be an obvious and immediate target
for an enemy missile. The center of the network would be the very first place to
go.

RAND mulled over this grim puzzle in deep military secrecy, and arrived at a
daring solution. The RAND proposal (the brainchild of RAND staffer Paul Baran)
was made public in 1964. In the first place, the network would have no central
authority. Furthermore, it would be designed from the beginning to operate while
in tatters.

The principles were simple. The network itself would be assumed to be unreliable
at all times. It would be designed from the get-go to transcend its own
unreliability. All the nodes in the network would be equal in status to all
other nodes, each node with its own authority to originate, pass, and receive
messages. The messages themselves would be divided into packets, each packet
separately addressed. Each packet would begin at some specified source node, and
end at some other specified destination node. Each packet would wind its way
through the network on an individual basis.

The particular route that the packet took would be unimportant. Only final
results would count. Basically, the packet would be tossed like a hot potato
from node to node to node, more or less in the direction of its destination,
until it ended up in the proper place. If big pieces of the network had been
blown away, that simply wouldn't matter; the packets would still stay airborne,
lateralled wildly across the field by whatever nodes happened to survive. This
rather haphazard delivery system might be "inefficient" in the usual sense
(especially compared to, say, the telephone system) -- but it would be extremely
rugged.

During the 60s, this intriguing concept of a decentralized, blastproof, packet-
switching network was kicked around by RAND, MIT and UCLA. The National Physical
Laboratory in Great Britain set up the first test network on these principles in
1968. Shortly afterward, the Pentagon's Advanced Research Projects Agency
decided to fund a larger, more ambitious project in the USA. The nodes of the