Transcript Presentation1 - University of Worcester

COMP 1321
Digital Infrastructure
Richard Henson
University of Worcester
September 2015
What is this module about?
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On successful completion of the module, you should
be able to:
 Describe a range of digital platforms and networks and
explain the context for use of each platform
 Apply tools involving digital hardware and digital logic to
solve real world problems
 Explore the contents of a digital storage medium using
computer forensic software and extract information that
could be used as evidence
More Learning Outcomes
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Apply networking principles to provide connectivity
between digital devices on a range of platforms that
can be used for sharing data and control of
processes
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Use penetration testing software, in accordance with
relevant standards and legislation, to identify
vulnerabilities
What is a computer?
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In small groups…
 Four attributes of a computer…
 What is it?
 What does it do?
 10 minutes
Are these computers?
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Abacus
Bathroom scales
Thermostat
Pocket calculator
DVD player
Typewriter
Car speedometer
Stonehenge
Person
Microphone
History of Computing (Origins)
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3400 BC: counting in tens (Egypt)
2600 BC: Abacus (China)
1900-1600 BC: Stonehenge completed
260 BC: base-20 counting – including
zero (Maya – Central America)
Abacus
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Ref:
http://www.tased.edu.au/schools/rokebyh/curric/infotec
h/stage1/assign2/pre20th.htm
Stonehenge
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Ref: http://www.astro.virginia.edu/class/courses.html
History of Computing (Europe)
967 AD: Zero in the eastern hemisphere
(Muhammad Bin Ahmad)
 Around 1500: Design of mechanical
calculator (Leonardo da Vinci)
 1614: Logarithms (John Napier)
 1621: Slide rule (Edmund Gunter,
William Oughtred)
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Slide rules
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Ref: http://osaki.cool.ne.jp/other/other/sliderule/sliderule.html
History of Computing
(Europeans – continued)
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1642: Adding machine (Blaise Pascal)
1679: Binary arithmetic (Gottfried
Leibnitz)
1820s and 1830s: Charles Babbage’s
Difference Engine and Analytical Engine
1840s George Boole: Boolean Algebra
– algebra using just 0 and 1
Babbage
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Ref: http://w1.131.telia.com/~u13101111/merschwib.html
Boole: inventor of “digital”
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Would be 200 years
old this year…
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Work buried from
his death (1864)
until the 1930s…
Ref: http://buttrysymicaela.blogspot.co.uk/2010/06/george-boole.html
European Domination
(mostly British)
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1835: Electric Relay (Davy)
1843: The idea of Computer Programming
(Ada Lovelace (Byron) )
1904: Vacuum tubes (“valves”) birth of
electronics
(John – not Alexander - Fleming)
The Second World War
 1936: Programmable computer (Konrad Zuse,
Germany)
 1943: Colossus, based on relays – won the war?
Colossus – what’s that!
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Top secret code breaker … 9000 people worked at
Bletchley Park during ww2… above, two of them…
http://www.youtube.com/watch?v=JF48sl15OCg
http://www.youtube.com/watch?v=46SI79feHT4
Bletchley Park (shhh… Top secret!)
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Set up in 1940 to crack German
codes…
succeeded… estimated that war shortened
by 2 years
but no-one could talk about it!
In 1985 one of the great codebreakers
wrote a book…
» but authorities disapproved, made his life difficult,
and he died young. Name: Gordon Weichman:
» http://www.bbc.co.uk/iplayer/episode/b069gxz7/bletchley-parkcodebreakings-forgotten-genius
US domination
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Late 1930s: Shannon used Boolean Logic
1947: Transistor (John Bardeen, Walter
Brattain & William Shockley)
1949: ENIAC First commercial computer
1960s: First minicomputer, the DEC PDP-1
(Program, Data, Processor)
UK computing
in the 50s & 60s
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The first “electronic brain”
http://www.bbc.co.uk/programmes/b069r3rt
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The first electronic office:
http://www.bbc.co.uk/programmes/b069rvb4
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The first electronic lottery:
http://www.bbc.co.uk/programmes/b069rvb4
US more domination…
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1967: Relational database
1969: Internet begins with 4 mainframes
1971:Floppy disks (IBM: Alan Shugart et al.)
1972: Intel, microprocessor
1975: Apple, first microcomputer
1976: Microsoft, computer language on a chip
1981: IBM PC launched with Microsoft
Operating system, MS-DOS
Programming

“A computer will do what you tell it to
do, but that may be very different from
what you had in mind.”
Joseph Weizenbaum
European Comeback?

1988: ARM CPU chip (Acorn)
used in many mobile phones
1991: World Wide Web founded at EU
research facility, CERN, under the
Swiss Alps (Sir Tim Berners-Lee)
 Late 1990s: Linux & Nokia

Development of Infrastructure
Input-output extended through dumb
terminals (Wang, 1970s)
 Linked together

Peer-peer networks (Internet…)

Networks evolve into client-server
(1980s)
client-end usable by non-specialists
Networking: Integration of
Telephone & Digital Infrastructures
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OSI model (1978)
 International Standard in 1984
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European (French) domination
 stubbornly analogue…
 digital data had to be converted before
transmission
 very slow evolution…
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Gradual evolution to digital telecoms
(1990s/2000s)
 ADSL and fast broadband (not rural areas…)
More US domination
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Mobile phone
i-player, i-phone, i-pad
Smart phone
Mobile apps
Tablets & e-books
Cloud computing
What next?… wetware?
And Now This…
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The credit card sized Raspberry Pi…
 designed in UK, and now manufactured in UK!
 available for resale at less than £30
Digits?
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Odd word… used to mean fingers and toes
 http://www.dribbleglass.com/Toes/uglytoes-2.htm
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Therefore about whole numbers of things
Gave birth to a hugely influential adjective…
DIGITAL
Digital but not whole?
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Now any quantity can become digital!
 based on approximation…
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Use “state” (on or off) to represent data
 presence/absence of an electric voltage
 low voltage or higher voltage
0-2 volts = off, 3-5 volts = on
 binary (off = 0, on = 1)
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numbers <-> electrical “square wave” pulses
 great for working with transistors…
Digital multimeter
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Ref: http://www.universalradio.com/catalog/fm_txvrs/03850208.html
Analogue (as it really is…)
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Uses physical entities to represent data
exactly
e.g. the size of an electric voltage, the
frequency of a signal, etc.
Analogue multimeter
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Ref:
http://www.kpsec.freeuk.com/multimtr.htm
Analogue and Digital
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The real world has always been
analogue…
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Digital World = post-war human
invention
 thanks to George Boole… 100 years earlier
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Discussion:
analogue or digital… which is best?
Summary
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No fuzziness in digital: exact value
No fractions in digital: precision of value
limited to last digit
Electronics easier with digital
Precision of instruction is crucial:
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Computers don’t need tea-breaks (!)
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