From the Archives
Making a Difference
Alumni Travel Program
A BRIEF HISTORY
OF THE 'NET
ARPANET originally was envisioned and funded by the Department
of Defense to link the computers of a few researchers. (Over its history,
the research arm of the defense agency has been known both as ARPA and
as DARPA.) The first node was established at UCLA in late 1969. A month
later, a second node was created at Stanford, and the network began
to expand. During the late 1970s and early 1980s, the network grew to
a few hundred nodes, recalls Ken Vastola. It included most major universities
and a number of military research sites.
In 1985, the National Science Foundation (NSF) recognized the importance
of the network to university researchers and got involved. The military
portion of the Net was spun off with the ".mil" designation.
By the late '80s, the network was commercialized, with ISPs making Internet
e-mail service available to customers. Experiments with voice and video
also began. In the early 1990s, the concept of the World Wide Web was
Backbone service providersbig phone companies such as MCI and
Sprint as well as services like AOLnow have core networks that
work together through cooperative agreements. Smaller companies obtain
their own pipelines through contracts.
Every message is broken into little blocks of data known as packets
and sent out over communications links such as phone, cable, or optical
fiber lines to machines known as routers. The router reads the address
on the packet and sends it on to another router that can get it to its
destination. Routers around the world, for example, use a numerical
address that represents the domain "rpi.edu," and send messages
so addressed to the Troy campus. Rensselaer then has its own routers
and intranetwork to forward those messages to their ultimate destination.
Unlike a letter sent through the mail or a package carried by Federal
Express, no one has responsibility for the message from beginning to
end, and there are no guarantees, Vastola notes. While organizing a
conference, he recently sent e-mails to 12 people around the world.
Most received the message within minutes. Five days later, one recipient
in Houston still had not seen his.
When a router is flooded, it puts some packets into a buffer. When the
buffer is full, the router begins to drop packets. Problems will get
worse as exponential growth continues and people download more and larger
files, Vastola says. But with increasing commercial use of the network,
people will demand more efficiency and reliability, not less.