bodmas blog

• BBC News article about computer storage devices bought on eBay
• Disklabs web site

Simply formatting the hard drive of your computer does not remove the files – the process removes the ‘index’ that keeps track of the location of your data on the disc.

That is good news for forensic investigators – a look at the disklabs Web site will show you how much data can be recovered – but bad news if you sell your computer or an older hard drive on the well known online auction site. It may be possible to recover passwords and Web addresses from your old hard drive.

Mac OS X has an option for ‘clean install’ of the operating system – a clean install removes all the data from the hard drive, and you get the option of writing zeros to all the locations on the drive (takes hours…). Even that is not foolproof – military standard software writes random data to each storage location three times over.

For Windows computers or computers that can boot from an MS-DOS system floppy you can use Kill Disc. The free version gives you zeros written to each location – same as Mac OS X.

• Helping Your Visitors – a State of Mind useful article from A List Apart in its new retro 50s look
• John December suggests an audience analysis table – I find this useful
• John December suggests a simple structure for Web development including processes and elements
• Download audience analysis table in PDF format

I use the blog format for course sites because students want to know “what did I miss last week” or “What was the homework”. I provide links to course documents in PDF format so they can find things quickly if a deadline is approaching. They can use the search box to find older posts.

• Tanniemola B. Liverpool has a personal home page on Leeds Uni server with a number of inspirational quotes. You can download some papers in PS format (no problem on the iBook but you will need Ghostscript on Windows) but there are dead links.
• Not Art, Science has diaries by 10 younger generation scientists

10 scientists kept a diary for a week – and the results are available as a book. Excellent stuff for motivating younger scientists – but warn them about the fixed term grant funded job….

Dr Liverpool is frank about his reluctance to leave London and the need for a career structure in science.

• Survey summary from Age Concern

Very

So it would seem from a recent Age Concern survey. The main findings:

• From 55 years old ageism outweighs any other form of discrimination including gender or ethnicity
• Young people feel they are dismissed as shallow larger louts sometimes as well
• One third of respondents said they found people over 70 as ‘incompetent and incapable’
• One third of people over 50 but under the state retirement age are not in paid employment

Methodology

• Sample size: 1800 roughly, so sampling error is around 2%, and a ‘representative sample’ of people over 16 was constructed – which I take to be a stratified sample so age groups represented composition of population in UK
• Questions were piloted first
• Questions and percentages in each response category broken down by age group are available in the summary report
• I have registered interest in the full report as a teaching aid – we shall see

• General information on Saturn’s ring system
• BBC News article on the spokes – gravitational effect of a moon

The Cassini probe has allowed astronomers to infer something about the dynamics and structure of the particles that make up Saturn’s rings, and solve a puzzle about the ‘spokes’ seen moving around the rings on a previous flyby.

The ring structure has fractal properties, the rings look the same at different scales, and a simple mathematical model called the Henon attractor can be used to generate ring like structures.

• Henon attractor formulas
• Java applet allowing you to zoom into the Henon attractor

The Java applet is one of several available as part of a Chaos course written by Michael Cross at CalTech.

• BBC news story on the arrest of the Zotob authors
• Sophos page with details of the Zotob worms

One of the virus writers lives in Morocco – a country not previously known for hacking – but it transpires that he lived previously in Russia, a country with severe economic problems and lots of out of work programmers.

Exploit code – the code that documents the vulnerability that allows commands to be injected into a target computer – was written by a Russian based hacker known only as houseofdabus. This use of handles is typical, as is the difficulty in tying people to real identities.

“Few virus writers now want to hit the front pages, said Mr Hypponen, most prefer to have their creations sneak under the radar, rack up a few thousand unwitting victims who are then milked for money or saleable data.”

Virus attacks are now organised for money and commissioned by criminal gangs. The need to transfer money provides a possible avenue for police to track down the writers – the only person to be caught so far for the London bank hack attempt was the recipient of funds in Israel.

Amazingly, a University of Pennsylvania security specialist was able to chat to the writer of the virus – handle diab10 – while investigating a phishing attack on the University e-mail server.

“During the chat, Diabl0 revealed that the Mytob worm had a very sneaky purpose. One of its intentions was to lower security settings on Microsoft’s Internet Explorer browser so certain pop-up adverts would not be blocked.

Diabl0 said he would be paid by the pop-up ad makers for every user hit. Even if the compromised users managed to remove the virus, bragged Diabl0, the settings would likely go unchanged and the stream of unwanted adverts would continue.

Every time an ad was sent to a user, Diabl0 would get credited with a click. With Zotob being one of the worst outbreaks of 2005, Diabl0 could have expected a bumper payday. “

The runaway spread of the virus lead agencies to take action.