No One is Listening
By MortazaviBlog on May 11, 2006
IHT reports on a recent article on wiretapping in the U.S.
The article, in USA Today, said that the agency did not listen to the calls, but secretly obtained information on numbers dialed by "tens of millions of Americans" and used it for "data mining" - computer analysis of large amounts of information for clues or patterns to terrorist activity.
Anne Marie Squeo of The Wall Street Journal covers the same story. (A paid subscription may be required to access this article.) She and Shawn Young, another WSJ contributor, give a nice summary of the technical aspects involved.
There is no disputing that the sheer volume of modern digital communications has made surveillance more difficult. Billions of emails are sent daily. The number of international calls made from the U.S. climbed to 7.4 billion in 2003 from 200 million in 1980, according to the Federal Communications Commission. Intelligence agencies are threatened with information overload.
Older analog communications mostly traveled over dedicated voice channels, making interception much easier. In a December 2000 report provided to incoming President Bush, the NSA warned that the digitization of voice, data and multimedia created volume, velocity and routing problems. As a result, the report said, intelligence analysts need to continually monitor communications traffic.
...When the communications data come ashore, they flow through a device known as a demultiplexer, which directs them to their destinations. By attaching a piece of equipment called a duplicator, investigators can copy everything traveling through the fiber-optic pipe.
Among other things, signals traffic reveals who is contacting whom and what circuit they are communicating over. Every time a phone call is placed or attempted or an email is sent, a record is generated. There is an international protocol for this information, called Signaling System 7, which makes it easier to track.
Data-mining technology also lets the government use other types of data to establish connections between individuals. Jeff Jonas, chief scientist for International Business Machine Corp.'s Entity Analytic Group, created link-analysis software that searches through readily available databases of phone numbers, addresses, frequent-flier numbers and the like to establish ties between people. After the Sept. 11 attacks, he used the software to connect two names already on the U.S. terrorist watch list to all 19 of the hijackers.
There was a time when physics had controversial uses. Now, it is the turn of algorithms.