Workshop 7

Connected Computers

1. How to make reliable systems from unreliable parts?

2. Societal impact of computers?

3. Collective intelligence and the World Wide Web?

Licklider at MIT 1942 Harvard Psycho-Acoustic Lab

1950 MIT started Lincoln Labs – Lick headed human engineering group

Lincoln Labs built the monster Sage computer to monitor early warning radar. The visual information was displayed on screens leaving human operators to interpret it. IBM Sage Computer Ad,

1960 (3 minutes) cache

1960 Lick published "Man-Computer Symbiosis“ (full text) “Men will set the goals, formulate the hypotheses, determine the criteria, and perform the evaluations. Computing machines will do the routinizable work …”

Katie Hafner & Matthew Leon, Where wizards stay up late – good source on Licklider

Intergalactic computer network

1962 Licklider conceived a global computer network at Bolt, Beranek and Newman

"Topics for Discussion at the Forthcoming Meeting, Memorandum For: Members and Affiliates of the Intergalactic Computer Network“ 1963

Consider the situation in which several different centers are netted together, each center being highly individualistic and having its own special language and its own special way of doing things. Is it not desirable, or even necessary for all the centers to agree upon some language or, at least, upon some conventions for asking such questions as “What language do you speak?” At this extreme, the problem is essentially the one discussed by science fiction writers: “how do you get communications started among totally uncorrelated “sapient” beings?” …

Claude Shannon – Information Theory

1940 Master’s thesis at MIT: A Symbolic Analysis of Relay and

Switching Circuits – Boolean algebra could be used to design digital circuits

1943 Briefly worked with Alan Turing on cryptography

1948 A Mathematical Theory of Communication – Shannon proposed encoding messages in a way similar to telegraphy, i.e. frequent letters such as ‘e’ and ‘s’ are encoded by short sequences, infrequent ones suck as ‘x’ by long ones. Given transmission line characteristics, it is possible to assign an upward limit to the information that can be carried.

James Gleick, The Information Good source for Shannon

Tech Icons: Claude Shannon (8 minutes) cacheClaude Shannon - Father of the Information Age (30 minutes) cache

Origins of the Internet – The Arpanet

ARPA (defense dept.) was supporting research at diverse campuses

The projects required extensive computer resources

The computers systems differed and could not communicate with each other

Research was often duplicated

Nuclear annihilation threat

With communications down countries could not respond in a measured way

This favored pre-emptive attack

Robust communications would give more time for a deliberate response

ARPAnet - the team behind the internet (6 minutes) cache

Network topology

The balls are nodes (computers)

The lines are links (wires)

Which topologies have a single point of failure? (node or link)

Which topology is most likely to survive an attack?

Packet Switching

Goal: Remove need for a dedicated (phone line?) circuit

Break a message into small packets

Label each packet with destination and source addresses + packet number + …

Packets may be routed differently to balance network traffic

At destination message is reassembled

Missing or damaged packets are resent

Developed independently by Paul Baran at the RAND Corporation and Donald Davies in the UK

                  

How does a packet travel the network? by Susana Rios (3 minutes) cache

Understanding the OSI Reference Model (10 minutes – gets technical) cache

High Tech Heroes #32: Paul Baran (28 minutes) cache

The World Wide Web

Tim Berners-Lee: The next Web of open, linked data (17 minutes) cache

Marc Andreessen On The Internet's Early Days – Talks about developing MOSAIC browser at Univ. Of Illinois (4 minutes) cache

From The Guardian

Search Engines

Alta Vista Launched 1995 created by DEC, subsumed into YAHOO and shut down in 2013

Alta Vista ad featuring Garry Kasparov cache

Terry Winograd

Thesis advisor Seymour Papert

Spcialty: human-computer interaction HCI

At Stanford had students Larry Page & Sergei Brin

How Search Engines Work (6 minutes) cache

Chart showing How Google Works

Open Source & Free Software

Feedback loops – Cybernetics

1983 Richard Stallman launched GNU EMACS

Free software, free society: Richard Stallman at TEDxGeneva 2014

(13 minutes) cache Linus Torvalds: 2014 Computer Pioneer Award (9 minutes) cache

Wikipedia

TED　 Jimmy Wales　 The Birth of Wikipedia (20 minutes) cache

Social Networking

2003 MySpace

2004 Facebook The Illustrated Story of Facebook (2 minutes) cache

An Interview with Mark Zuckerberg (9 minutes)

Further Reading

Hafner, Katie, Where Wizards Stay Up Late: The Origins of The Internet, Simon & Shuster, 1998.

Berners-Lee, Tim, Weaving the Web: The Original Design and Ultimate Destiny of the World Wide Web, Harper-Collins, 2000.