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OU Notes
A Brief History of the Future
The Author explains his personal background and fascination with communications facilitated through the 'net. Compares communications systems of 1956 with those of 1997.
This chapter essentially explains the basic concepts of hardware involved.
- MODEM:- Communications channel along which signals flow
- BANDWIDTH:- The capacity of the 'electronic pipe'. Term comes from the spread (or band) of frequencies that the channel can pass. The bandwidth of the human ear is approx 18kHz. The bandwidth of a channel is goverend by its' physical properties e.g. copper cable etc.
- FREQUENCY:- Measured in cycles per second or Hertz (Hz). Bass sounds have low frequencies (e.g. 50Hz) whereas high sounds have high frequencies (e.g. 18,000kHz)
- URL:- Uniform Resource Locator
- IP Number:- Internet Protocol number (the machine's net address). A unique address of each machine on the 'net. Four sets of digits separated by full stops, e.g. 148.176.237.68
'Always on' machines have designated permanent IP addresses, whereas dial-up machines are assigned a temporary unique IP address
- PACKETS:- The small chunks data is broken into for transmission. Packets are 1500 characters long and are transmitted in electronic 'envelopes'.
- TCP:- Transmission Control Protocol - The agreed procedure for dissassembling and reassembling messages
- TCP/IP:- The building blocks of net activity in the way DNA is to the biological world.
- PACKET SWITCHED SYSTEM:- Countless machines transferring packets via TCP/IP. Machines transmit packets through different routes after having scanned the address of the 'envelope' and establishing that the packet was addressed to a different machine. Packets may arrive in the wrong order but the TCP program checks each of them in, assesses the correct order via the 'envelope' information, assemles in the correct order and requests retransmission of lost or incomplete packets. The assembled message is transmitted to the browser.
- Refer to page 38 for ideas about the Internet as an organism rather than machinery - "a living embodiment of an open-market on ideas" - Biological metaphor - Page 51 later uses the 'big bang' as a metaphor for human creativity.
- Discusses the popularity and enormity of the internet as a communications medium and the negative myths surrounding it, such as the insecurity of e-commerce, internet addiction, violence and pornography.
- METACOMPUTING:- Co-operative way of using networked computers (e.g. SETI project) - the application of Metcalfe's Law which states that the power of a network increases as the square of the number of computers connected to it.
- Dyson's Symbiotic Evolution - 3 stage process
- Cretion and dissemination of mainframe and minicomputer ('60's-'70's)
- Creation and mass-production of microcprocessor and dissemination of operating systems on floppy disk
- Technical protocols such as TCP/IP
- Dyson states that the net is qualitatively different from other technology systems because of its 'emergent behaviours' - perhaps new forms of A.I. will emerge from its' densely interconnected systems?,/li>
- Dyson's conjectures about A.I. and thr net fail to mention the role of people in the process and network. The 'wired' population is heavily skewed towards the developed world, and there is even a digital divide within these parts of the world.
- Rheingold thinks people predominately use the net for:-
- Entertainment and information
- Virtual communities - geographically dispersed people with common interests. The net has no central authority - anyone can join.
- Weinreigh asks "how far can mediated contact constitute community?" and concludes that they are no substitute for the sensual experience of real-life contact.
- John Gilmore:- "The Net interprets censorship as damage and routes around it."
References to modern technology in pre and post-war literature. Naughton asks how far back one should trave the history of the Internet?
- 1830 - Charles Babbage planned the 'analytical engine' which performed arithmetical functions through punch cards. This would be a good starting point, if it weren't for Leibniz in 1673, Pascal in 1642, Schikard in 1623... where to start?!
- MIT: Massachusetts Institute of Technology - this was founded in 1861 by William Barton Rogers. 3 people from here are often cited as the origin of the 'net:- VANNEVAR BUSH, NORBERT WEINER & J.C.R. LICKLIDER
- VANNEVAR BUSH (1890-1974):- Electrical engineer, ex-dean at MIT. Created the DIFFERENTIAL ANALYSER in 1925 - a huge analog computer for solving differential equations, It 'acted out' rather than computed.
- NORBERT WEINER (1894-1964):- Mathmetician at MIT. Worked with BUSH on the differential analyser. Wiener was the son of Jewish immigrant parents - his father became Chair of Harvard. Norbert Weiner published his magnum opus in 1948:- Cybernetics: Control and Communication in the Animal and the Machine. The paper concerned itself with information which drives feedback control - this is ubiquitous in animal and mechanical worlds.
- CYBERNETICS:- Derived from the Greek for 'steersman'
- Weiner was fascinated with the work of CLAUDE SHANNON who worked at MIT on a project to eliminate noise in an electronic circuit like a telephone system. Shannon later worked for Bell Labs (AT&T)
- THE SHANNON MODEL:- Shannon developed a mathematical model for the process of communication:-
- SOURCE (e.g. a telephone user> ... uses an
- ENCODER (e.g. a telephone microphone)... to transform
- MESSAGE (e.g. the spoken word)... which transmits through
- CHANNEL (e.g. the phone network)... to reach a
- DECODER (e.g. earpiece of another telephone)... which translates soundwaves for
- RECEIVER (e.g. mind of another listener)
- This inspired invention of error-correction codes which make digital communications more robust and reliable than their analogue counterparts.
- The Shannon Model highlights gaps in theory and understanding e.g. how is it that humans can interpret messages almost overwhelmed by noise? Because human communications rely on REDUNDANCY - for example, take half the words from a written passage and sense could still be made.
- J.C.R LICKLIDER (1915-): Harvard, later M.I.T.
Was fascinated by Weiner's work on human-computer relationship (Computer=Algorithmic, Human=heuristic - open ended, trial & error etc.).
- These co-operative and interactive relationships were hard to attain at the time when computers were still batch-processing punch-card run enormities requiring air-conditioned machine rooms.
- 1947 - Licklider
Last updated on Friday, 31-Oct-2003 09:05:37 GMT
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