COMP 1321 COMP 1321 Digital InfrastructureDigital Infrastructure

Richard HensonRichard Henson

University of WorcesterUniversity of Worcester

SeptemberSeptember 20152015

What is this module about?What is this module about? 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 OutcomesMore Learning Outcomes

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

Use penetration testing software, in accordance with relevant standards and legislation, to identify vulnerabilities

What is a computer?

In small groups…

Four attributes of a computer…What is it?What does it do?

10 minutes

Are these computers?

Abacus TypewriterBathroom scales Car speedometerThermostat Stonehenge

Pocket calculator PersonDVD player Microphone

History of Computing (Origins)

3400 BC: counting in tens (Egypt)2600 BC: Abacus (China)1900-1600 BC: Stonehenge completed260 BC: base-20 counting – including zero (Maya – Central America)

Abacus

Ref: http://www.tased.edu.au/schools/rokebyh/curric/infotech/stage1/assign2/pre20th.htm

Stonehenge

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)

Slide rules

Ref: http://osaki.cool.ne.jp/other/other/sliderule/sliderule.html

History of Computing (Europeans – continued)

1642: Adding machine (Blaise Pascal) 1679: Binary arithmetic (Gottfried Leibnitz) 1820s and 1830s: Charles Babbage’s Difference Engine and Analytical Engine1840s George Boole: Boolean Algebra – algebra using just 0 and 1

Babbage

Ref: http://w1.131.telia.com/~u13101111/merschwib.html

Boole: inventor of “digital”

Ref: http://buttrysymicaela.blogspot.co.uk/2010/06/george-boole.html

Would be 200 years Would be 200 years old this year… old this year…

Work buried from his Work buried from his death (1864) until death (1864) until the 1930s…the 1930s…

European Domination (mostly British)

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 War1936: Programmable computer (Konrad Zuse,

Germany)1943: Colossus, based on relays – won the war?

Colossus – what’s that!

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!)Bletchley Park (shhh… Top secret!)

Set up in 1940 to crack German Set up in 1940 to crack German codes…codes…succeeded… estimated that war shortened succeeded… estimated that war shortened

by 2 yearsby 2 yearsbut no-one could talk about it!but no-one could talk about it!In 1985 one of the great codebreakers In 1985 one of the great codebreakers

wrote a book…wrote a book…» but authorities disapproved, made his life difficult, but authorities disapproved, made his life difficult,

and he died young. Name: Gordon Weichman:and he died young. Name: Gordon Weichman:» http://www.bbc.co.uk/iplayer/episode/b069gxz7/bletchley-park-http://www.bbc.co.uk/iplayer/episode/b069gxz7/bletchley-park-

codebreakings-forgotten-geniuscodebreakings-forgotten-genius

US domination

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 UK computing in the 50s & 60sin the 50s & 60s

The first “electronic brain”The first “electronic brain”http://www.bbc.co.uk/programmes/b069r3rt http://www.bbc.co.uk/programmes/b069r3rt

The first electronic office:The first electronic office:http://www.bbc.co.uk/programmes/b069rvb4 http://www.bbc.co.uk/programmes/b069rvb4

The first electronic lottery:The first electronic lottery:http://www.bbc.co.uk/programmes/b069rvb4 http://www.bbc.co.uk/programmes/b069rvb4

US more domination…US more domination… 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

ProgrammingProgramming

“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 togetherPeer-peer networks (Internet…)

Networks evolve into client-server (1980s)client-end usable by non-specialists

Networking: Integration of Telephone & Digital Infrastructures

OSI model (1978) International Standard in 1984

European (French) dominationstubbornly analogue…digital data had to be converted before

transmissionvery slow evolution…

Gradual evolution to digital telecoms (1990s/2000s)ADSL and fast broadband (not rural areas…)

More US domination

Mobile phone i-player, i-phone, i-pad Smart phone Mobile apps Tablets & e-books Cloud computing What next?… wetware?

And Now This…

The credit card sized Raspberry Pi…designed in UK, and now manufactured in UK!available for resale at less than £30

Digits?

Odd word… used to mean fingers and toes http://www.dribbleglass.com/Toes/uglytoes-2.htm

Therefore about whole numbers of things Gave birth to a hugely influential adjective…

DIGITAL

Digital but not whole?

Now any quantity can become digital!based on approximation…

Use “state” (on or off) to represent datapresence/absence of an electric voltage low voltage or higher voltage

0-2 volts = off, 3-5 volts = onbinary (off = 0, on = 1)

numbers <-> electrical “square wave” pulsesgreat for working with transistors…

Digital multimeter

Ref: http://www.universal-radio.com/catalog/fm_txvrs/03850208.html

Analogue (as it really is…)

Uses physical entities to represent data exactlye.g. the size of an electric voltage, the

frequency of a signal, etc.

Analogue multimeter

Ref: http://www.kpsec.freeuk.com/multimtr.htm

Analogue and Digital

The real world has always been analogue…

Digital World = post-war human invention thanks to George Boole… 100 years earlier

Discussion: analogue or digital… which is best?

Summary

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:

Computers don’t need tea-breaks (!)