The Internet: Behind the Web
The History Channel
The process began in the 1950s
Robert Lickliter: Psychologist at MIT envisioned linking computers
The agency that started it all
ARPA: Advanced Research Projects Agency created by President Eisenhower to address and solve the communication problem in the
event of a nuclear war with Russia.
Bob Taylor at ARPA: Got frustrated with having to use different computes to talk to main frames
DARPA: Current name for ARPA discussed above.
Leonard Kleinrock: Applied queuing theory to handle packages of data
Demand access: Get it when you need it
Distributed control: No node, etc, controls entire network
BBN
Bolt Beranek and Newman (BBN), the Cambridge, MA team that designed and deployed the Interface Message Processors (IMP) for the
ARPA Network in 1969.
Company that won contract to demonstrate the initial concepts.
Frank Heart: Project manager at BBN
Interface Message Processors (IMPS):
Computers that knew how to communicate with others on the network.
Individual computer needed to only know how to communicate with the IMPS
ARPA Net
Network of ARPA computers.
Arpanet (Advanced Research Project Agency Network) the Internet predecessor, started in
1969.
The first four nodes (networks) consisted of UCLA, UCSB, University of Utah and SRI.
Arpanet was finally decommissioned in 1990 having been largely replaced by the NSFNet (National Science Foundation Network).
Raymond Tomlinson
Developed the first “killer ap”, Email.
Started the use of the @ sign because that was where a person was at.
LAN
Local Area Network
Example: In a building
WAN
Wide Area Network
Example: Among buildings
Internet
Connected networks
The question then arose – could different networks be connected?
TCP/IP
Transmission Control Protocol/Internet Protocol.
A protocol developed for communications over interconnected, sometimes dissimilar, networks.
Vinton Cerf and Robert Kahn: Co-inventors of TCP/IP - 1973
IP is responsible for moving packet of data from node to node. IP forwards each packet
based on a four byte destination address (the IP number). The Internet authorities assign
ranges of numbers to different organizations. The organizations assign groups of their
numbers to departments. IP operates on gateway machines that move data from
department to organization to region and then around the world.
TCP is responsible for verifying the correct delivery of data from client to server.
Data can be lost in the intermediate network. TCP adds support to detect errors or lost data
and to trigger retransmission until the data is correctly and completely received.
983: TCP/IP adopted as the protocol to be used by all
Gateway: Computer that knew the protocols and controlled access across networks.
1992: Congress passed bill placing Internet in public domain and not restricted to government agencies – major milestone
Problem with future expansion lay in the difficulty at the time to find information on the internet.
Tim Berners Lee
Developed software in 1992, while working at CERN, to track information on the Internet.
Referred to the network the World Wide Web.
Considered the father of the WWW.