vigilant TV

New Scientist reports on an email traffic analysis technique developed at HP’s Palo Alto labs, that can reportedly help identify groups and leaders. Note to paranoid: use Mixmaster; it’s specifically designed to defeat this kind of analysis.

“If the CIA or another intelligence agency has a lot of intercepted email from people suspected of being part of a criminal network, they could use the technique to figure out who the leaders of the network might be,” says Joshua Tyler of Hewlett-Packard’s labs in Palo Alto, California. At the very least, it would help them prioritise investigations, he says. Tyler and his colleagues Dennis Wilkinson and Bernardo Huberman,
study email communication patterns and communities among networks of
people. The trio wondered if they could identify distinct communities within Hewlett-Packard’s research lab simply by analysing the IT manager’s log of nearly 200,000 internal emails sent by 485 employees over a couple of months. They plotted the links between people who had exchanged at least 30 emails with each other, and found the plot included 1110 links
between 367 people. In a network as large and complex as this, the plot alone will not tell you which groups people are. So to pick them out, the researchers used a computer algorithm that looks for the critical links that form bridges between separate
groups – what the team calls links with high “betweenness”. By severing
these links one by one, the algorithm gradually isolates people into different communities of groups who are emailing each other.

[...]

The technique revealed 66 communities at the lab. And when the researchers compared the community members with the company organisation charts, they found that 49 of them contained people who all worked in the same department. In most of the others, the people were collaborating on a project. In a second investigation, the team plotted the same network of
emails using a standard algorithm that, in effect, tries to arrange it in
the least tangled way possible. This showed that the managers, including the director, tended to cluster in the middle. “This approach puts in the middle the people who have the most diverse range of contacts in the organisation – and these tend to be the leaders,” says Tyler. – New Scientist, Email traffic patterns can reveal ringleaders.