Cryptography Reference
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8.6 History of the Internet and the WWW
Networks aren't made of printed circuits, but of people
Cliff Stoll
— from The Cuckoo's Egg (see [273, page 392])
It is appropriate to close this chapter with a look at the origins of the
stage upon which the applications (which we have been describing), perform,
the Internet and World-Wide Web (WWW), the principal information retrieval
scheme for the Internet. The Internet is the system architecture underpinning
the globally interconnected network of computers, the set of all the computer
networks connected, via routers, all over the globe. 8.23 Now we look at where
they began, how they developed, and how the infrastructure evolved.
Computer networks existed as far back as the late 1950s in the form of
special-purpose systems (such as the inception of the airline registration sys-
tem called SABRE). By the early 1960s, time-sharingsystems were in use in
many leading-edge corporations. These systems allowed multiple employees
of the firm to access the computer virtually simultaneously. Such computers
came to be known as hosts , and with a vision toward a host-to-host network.
By 1969, the first implementation of a host-to-host, general-purpose network
was put into service, called ARPANET, for the U.S. Department of Defence's
Advanced Research Projects Agency (ARPA). 8.24 ARPANET supported host-
to-host, time-sharingconnections in the United States, mainly at overnment-
supported research sites such as universities. 8.25 ARPANET also contained one
of the first e-mail manifestations in the form of a protocol called simple mail
transfer protocol (SMTP). 8.26 From SMTP evolved the file transfer protocol
(FTP) needed for use with much larger data packages than those typically en-
countered in an e-mail transmission. In order to process these bigger blocks of
data, ARPANET used a new segmenting mechanism called packet switching ,
which broke down large blocks of data into manageable packets for independent
dispatch, and later reconstruction at the target site. This new notion for pro-
cessingof packets via segmentation and reconstruction was one of the earliest
means of communication without a dedicated channel. 8.27 Although packet net-
works were created in the privat e sector in the 1970s, such as Telnet in the U.S.,
8.23 There exist isolated internets that are not connected to the Internet, but still follow
Internet Standards (see RFC 1602, [193]).
8.24 The RFC series (see Footnote 7.2 on page 262), began in 1969 as part of ARPANET.
8.25 However, the military people wanted separate communications, so they created Milnet ,
which nevertheless, remained connected and accessible by ARPANET users.
8.26 The other modern-day e-mail standard is Post O(ce Protocol (POP). When e-mail arrives
at an SMTP server, it is forwarded to a POP server where it is stored until accessed by the user
who logs on to the POP server with username and password. Then the POP server retrieves
the mail and sends it. The newest version, POP3, can be used with or without SMTP.
8.27 A dedicated channel is a channel reserved exclusively for one type of communication. The
term is often used to mean a leased or private line . On the other hand, a dedicated server is
a particular computer in a network reserved specifically for the purpose of fulfilling the needs
of the network. Typically, however, most servers are not dedicated in today's world, since
the computer may be employed to be a server in addition to performing other duties. The
antithesis of dedicated is general purpose .
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