Wednesday, March 24, 2010

Ada Lovelace Day: Barbara Liskov and Data Abstraction



Today is Ada Lovelace Day, a day to blog about female computer scientists we admire. Augusta Ada Byron, Countess of Lovelace (10 December 1815 – 27 November 1852) is credited with authoring the first computer algorithm (which concerned a method for calculating a sequence of Bernoulli numbers) in 1843 for use on Charles Babbage's early mechanical general-purpose computer, the analytical engine.




This year I'm going to write a posting on MIT professor Barbara Liskov who won the 2008 ACM Turning Award for 'foundational innovations' in programming language design. Barbara Liskov has worked at MIT AI lab since 1972, and one of her most significant contributions to the field of computer science is her work on championing the idea of Data Abstraction (which seperates the implementation from the use of complex data types). She also designed CLU, an object-oriented programming language incorporating clusters to provide coherent, systematic handling of abstract data types. Following this she developed Argus, a distributed programming language whose novel features led to further developments in distributed system design that could scale to systems connected by a network.

Without her work we would not have programming languages like C++ and Java, without her work we wouldn't have distribtued databases and innovations in real-time systems, without her work we wouldn't have Cloud Computing, thank you Barbara Liskov.

This is a video of Barbara Liskov discussing Practical Byzantine Fault Tolerance from December 3, 2001, Running Time: 00:55:32
http://mitworld.mit.edu/video/43

Thursday, February 18, 2010

The Irish Times: Reeling in the hackers

http://www.irishtimes.com/newspaper/finance/2010/0219/1224264787078.html

A new study reveals that the popular film portrayal of computer hackers is actually quite accurate, writes KARLIN LILLINGTON

IF YOU don’t like the idea of a scholarly paper on the trail of hackers in films, then take it up with Damian Gordon’s parents. “I have to blame my parents – the only films we were ever taken to were science fiction and futuristic kinds of films,” says Gordon, a lecturer in computer science at the Dublin Institute of Technology.

Gordon has just published his paper, Forty Years of Movie Hacking: Considering the Potential Implications of the Popular Media Representation of Computer Hackers from 1968 to 2008, in the current issue of the International Journal of Internet Technology and Secured Transactions.

A self-confessed film buff, he likes to show students clips from such films as a teaching tool because he feels they bring an abstract subject to life and help initiate lively discussions.

“With computer science you’re always trying to explain complex ideas in a clear way. Clips from films can be very useful for that. Any time I can, I try to slip in a film clip.”

In trying to teach his students about security issues, he realised many had misguided notions about what the typical computer hacker is like and where security threats come from.

That set him thinking that perhaps the misperceptions came from the upper trails of hackers in popular culture.

So Gordon set out to compile a list of as many films that featured hacking as he could and came up with 50 – which he realises is not comprehensive and excludes foreign films, but does pick up most Hollywood films since the late 1960s that fit within his criteria outlined in the 29-page paper. He excluded animated films and documentaries, for example.

He included films from as early as 1968 through to 2008, across several genres from science fiction to crime films.

His paper observes a curious dearth of films in the 1970s, just as computing was coming into popular visibility. His theory is that a lifting of censorship rules caused films to focus more on violence and sex.

“Hacking computers was probably too passive and boring,” he laughs.

The aim of his paper “was really to investigate why there is a general public perception that hackers all seem to be teenagers in bedrooms. Lots of books on hacking talk about this, but it is so wrong. Most hackers are around 30 and are computer professionals.

“Being a hacker is really not about sitting alone in a dark bedroom. It has a lot more to do with your interpersonal skills.”

His film findings surprised Gordon just as much as they might surprise others. Far from having public perceptions of hackers shaped by films, he found that the celluloid portrayal of hackers was actually quite accurate – setting aside the unlikelihood of your average female hacker looking like Sandra Bullock or Angelina Jolie.

“It’s devastating to realise that most movies do portray hackers correctly,” he jokes.

First off, he found that the average age of the majority of film hackers was over 25, with only a quarter younger than that. Some 65 per cent were aged between 25 and 50, and only 3 per cent were older than 50, which he thinks is fairly accurate.

As for profession, 32 per cent were portrayed as working in the computer industry, 28 per cent were full-time hackers, 20 per cent were students and 20 per cent worked in other professions.

Gordon notes that this actually meshes fairly closely with reality – one study cited in his paper notes that the average hacker is 27 and either a computer professional or full-time hacker.

Gordon also found that, in the films, about 10 per cent of the hackers were women, which also approximates real-world statistics.

He notes that for some reason there are far more female hackers portrayed on television compared to film. “I’m presuming that’s because men tend to do the action bits on television,” he says.

Two areas in which film deviated from real-world hacking are the number of attacks depicted as coming from outside an organisation rather than being instigated from those inside an organisation, and the portrayal of the intentions of hackers.

In film, only 20 per cent of the attacks are internal, but industry studies suggest the ratio may be closer to 50-50, Gordon notes in his paper.

Also, the vast majority of hackers in films are actually portrayed as the good guys – a huge 73 per cent, with 10 per cent being somewhere in between, and 17 per cent portrayed as bad guys. “I was definitely surprised at the number of films showing hackers in a positive light,” he says.

However, he rather likes this himself, given that the term “hacker” started out as a positive one, referring to people who were highly adept at tinkering with electronics and writing or modifying computer programs. Only much later did the public start to use the term hacker to mean someone with malicious intent.

“I’d like to reclaim the title as a positive one,” says Gordon.

Damian's top five

Top Millions (1968) Peter Ustinov as Marcus Pendleton, a con-man just out of prison. “Really a great movie.”

Tron (1982) Jeff Bridges as Kevin Flynn, a former employee of fictional computer company ENCOM. “I adored Tron, and you can never go wrong with Jeff Bridges.”

Superman III (1983) Gus Gorman (Richard Pryor) discovers that he has an extraordinary talent for computer programming. “A great salami-slicing attack.”

WarGames (1983) David Lightman (Matthew Broderick) as a high school student who is highly unmotivated at school but is an enthusiastic computer hacker at home. “Fixed in people’s minds the archetype of the young hacker operating from his bedroom.”

Sneakers (1992, Heist) College students Martin Brice (Gary Hershberger) and his friend Cosmo (Jo Marr) use a college computer to hack into banking systems to transfer funds. “Fantastic film”