History (Development) of Computer Networks
History (Development) of Computer Networks
Communication before computer networks
○ At a very basic level, a network is a system for exchanging messages.
○ 2400 BCE: carrier system
○ July 26, 1775: United States Postal Service was established by the Second Continental Congress with Benjamin Franklin as the first Postmaster General
○ 1838: First commercial telegraph allowed messages to be exchanged between two points in the city of London 13 miles apart
» Samuel Morse simultaneously sent the first telegraph in the United States; Alfred Vail, his assistant, developed Morse code
○ 1876: First telephone conversation between Alexander Graham Bell and his assistant, Thomas A. Watson
○ 1895: First commercial radio capable of transmitting 1.5 miles was invented by Italian inventor Guglielmo Marconi
○ 1927: First working television with electronic scanning of both the pickup (i.e., video camera) and display devices was invented by Philo Farnsworth
Computer Networks
○ Motivation was to enable remote use of computers
○ Based on 1960s telephone network, which performs circuit switching
» A circuit is a dedicated communication channel, composed of a sequence of dedicated physical wires
» Telephone switchboard - originally circuits were established by manually connecting wires
» Circuit switching is inefficient because only two endpoints at a time can communicate over the channel
Late 1950s and early 1960s: ideas for packet switching
» Packet switching breaks a message into pieces (packets) and multiplexes packets from several endpoints over the same communication channel
1961: Leonard Kleinrock published a paper that showed packet switching was effective for bursty traffic - when two endpoints were not using the communication channel, other pairs of endpoints could send packets
1967: Paul Baran had been developing packet switching as Rand Institute and published his work; US Department of Defense wanted a robust communication system
1967 - 169: Team lead by Vint Cerf and Bob Kahn developed the ARPAnet (Advanced Research Projects Agency Network)
» First network switches built by BBN using the Internet Message Processor (IMP)
» First 4 node packet switched was built ¬¬ switches were deployed at Utah, UCLA, UCSB, and Stanford
1972 : ARPAnet had grown to 15 nodes
Network control protocol was the first end to end communication protocol defined by RFC0001; allowed endpoints to send a message and let the network worry about what path to take to get it there
1972 : Ray Tomlinson invented email; first network application; used the end¬to¬end communication protocol
1973 : Bob Metcalf invented Ethernet ¬¬ a standard for wiring and signaling that is still used today (with some updates)
○ 1974 : Vint Cerf and Bob Kahn developed an open architecture for the Internet
» Internet Protocol (IP) and Transmission Control Protocol (TCP)
1979 : Internet (formerly the ARPAnet) had 200 nodes
1989 : Internet had 100K nodes
» Much growth was fueled by connecting universities Larry Landweber from UW Madison was an important part of this
» TCP improvements by Van Jacobson to address congestion
» Domain Name System (DNS) developed to provide an easier way to identify nodes
1991: Tim Bernes Lee invented the Web by creating the Hypertext Transfer Protocol (HTTP)
1993: Mark Andreesen invented MOSAIC, the first graphical browser
1998: Google was incorporated; Napster peer to peer network for file sharing started
2000s: social networks, gaming, streaming media
2008: Open Flow protocol was designed by Nick McKeown, leading to software defined networking (SDN)
2???: You invent the next big thing for networking