1. COMP 1321 Digital Infrastructure
Richard Henson
University of Worcester
September 2017

2. What is this module about?
On successful completion of the module, you should be able to:
LO1: Describe a range of digital platforms and networks and explain the context for use of each platform
LO2: Apply tools involving digital hardware and digital logic to solve real world problems
LO3: Explore the contents of a digital storage medium using computer forensic software and extract information that could be used as evidence

3. More Learning Outcomes
LO4: 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
LO5: Use penetration testing software, in accordance with relevant standards and legislation, to identify vulnerabilities

4. What is a computer? In small groups… Four attributes of a computer…
What is it?
What does it do?
10 minutes

5. Are these computers?
Abacus Typewriter Bathroom scales Car speedometer Thermostat Stonehenge
Pocket calculator Person DVD player Microphone

6. History of Computing (Origins)
3400 BC: counting in tens (Egypt) 2600 BC: Abacus (China) BC: Stonehenge completed 260 BC: base-20 counting – including zero (Maya – Central America)

7. Abacus

8. Stonehenge

9. Calculating machines - Precursors to Computers (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)

10. Types of slide rule

11. (European calculating machines – continued)
1642: Adding machine (Blaise Pascal) 1679: Binary arithmetic (Gottfried Leibnitz)
1820s and 1830s: Charles Babbage’s Difference Engine and Analytical Engine

12. Babbage… And his analytical engine as reproduced in Sweden:

13. Boole: inventor of “digital”
Would be 202 years old this year…
Work buried from his death (1864) until the 1930s…

14. Boolean Algrebra 1840s George Boole… Whole new system of Algebra
used true/false instead of numbers
trying to produce a type of maths that related to philosophy
Inspiration for all of us!

15. Programming Started with Ada Lovelace (who?) Daughter of Lord Byron
Brought up on Maths (!)
Developed a friendship with Babbage
Wrote instructions for his machines…

16. European Domination of Hardware (mostly British)
1835: Electric Relay (Davy)
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?

17. Colossus – what’s that!
Top secret code breaker … 9000 people worked at Bletchley Park during ww2… above, two of them…

18. Bletchley Park (shhh… Top secret!)
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:

19. Like to go to Bletchley Park?
Includes a museum of Computing
Could be arranged as an all day visit…???

20. Digital Electronics “Digital” requires two states (eg on/off)
Electrical Relays achieved that… hence Colossus
Electronic Valves achieved that… hence ENIAC
Both very large and cumbersome

21. US domination (and why…)
Late 1930s: Shannon dug up Boole’s work
found a good fit between “true/false”, electronic “on/off” valves, and binary numbers “0/1”
used Boolean Logic to create circuits wit predictable outcomes
1940s Europe devastated by war…
1947: Transistor (John Bardeen, Walter Brattain & William Shockley)
like a valve but low voltage, low energy
1949: ENIAC First commercial computer
1960s: First minicomputer, the DEC PDP-1 (Program, Data, Processor)

22. UK computing in the 50s & 60s The first “electronic brain”
The first electronic office:
The first electronic lottery:

23. 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

24. US domination of software & hardware development…
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: Wang, first VDU

25. The First “Infrastructure”
Mainframes had no infrastructure
Separate area of their own…
Paper in… paper out!
VDU allowed interaction with mainframe
multiuser systems
needed communication protocols and cabling

26. More US Dmination… 1976: Microsoft, computer language on a chip
1981: IBM PC teamed up with Microsoft
first Desktop Operating system, MS-DOS used in Business
Standalone, so no infrastructure…

27. Growth of Infrastructure…
Suddenly, a requirement for computers to communicate with other computers…
Hardware & protocols further refined
networks grew rapidly
Mainframe-mainframe
PC-PC
even mainframe to PC!

28. Development of Infrastructure
Gradually replaced having one monster computer in one place…
Input-output extended through dumb terminals (Wang, 1970s)
Standalone desktop computers (1979)
Linked together (1980s)
peer-peer networks
evolve into client-server
client-end usable by non-specialists

29. Networking: Integration of Telephone & Digital Infrastructures
OSI model (1978)
International Standard in 1984
Telecoms…French domination
stubbornly analogue…
digital data had to be converted before transmission
very slow evolution…
Gradual evolution to digital telecoms (1990s/2000s)
ADSL and fast broadband (not rural areas…)

30. European Comeback? From 1988: Mobile phone
ARM CPU chip (Acorn)
low power… used in many devices
1991: World Wide Web founded at EU research facility, CERN, under the Swiss Alps (Sir Tim Berners-Lee)
Late 1990s: Linux & Nokia

31. More US domination i-player, i-phone, i-pad Smart phone Mobile apps
Tablets & e-books
Cloud computing
What next?… IoT, wetware?

32. Analogue gives way to Digital…
Computer Data… electronic (two states e.g. high/low voltage)
Became known as digital
Telephone system analogue (for historical reasons)
high/low voltages superimposed on a sound wave
transmission slow
easily intercepted…

33. Digits? Hence… DIGITAL!!! Odd word… used to mean fingers and toes
therefore about whole numbers of things
Gave birth to this hugely influential adjective…
Hence… DIGITAL!!!

34. Digital but not whole? Any quantity can become digital!
(not just about whole numbers)
based on approximation…
Electrical on/off “state” represents data as (1s/0s)
presence/absence of an electric voltage
low voltage or higher voltage volts = off, 3-5 volts = on
binary (off = 0, on = 1)

35. Digital multimeter
Ref:

36. What is Analogue? The “real” world
Everything before Boole’s digital logic started to be used by computers…
and programs could be written to depict the world
Uses physical entities to represent data exactly
e.g. the size of an electric voltage, the frequency of a signal, etc.

37. Analogue multimeter
Ref:

38. Analogue and Digital
The real world has always been analogue. Since long before humans walked the earth!
most inventions started out as analogue
Digital World ~ post-war human invention
based on George Boole’s maths… 100 years earlier
Discussion:
analogue or digital… which is best? Why?

39. Analogue to Digital Computers don’t do analogue!
Devices had to be invented to convent analogue data to digital
input devices
always an approximation (can be a very close approximation though…)

40. Summary of Developments
Digital only possible thanks to George Boole (1850s, UK)
Hardware began with Lord Babbage, but mechanical (1850s UK)
Programming started with Lord Byron’s daughter, Ada Lovelace (1850s UK)
Programmable analogue machines…
Electronics used Boole’s maths (1930s US)
Computers programmed digitally… (late 1940s on, US - almost complete domination)