August 29, 2007 | By Marcia Hofmann

EFF Documents Shed Light on FBI Electronic Surveillance Technology

The Electronic Frontier Foundation (EFF) has obtained documents through the Freedom of Information Act that reveal the inner workings of the FBI's Digital Collection System Network (DCSNet), a software suite that allows the Bureau to conduct surveillance on a wide variety of digital devices.

As Ryan Singel writes in his extensive report for Wired News:

Many of the details of the system and its full capabilities were redacted from the documents acquired by the Electronic Frontier Foundation, but they show that DCSNet includes at least three collection components, each running on Windows-based computers.

The $10 million DCS-3000 client, also known as Red Hook, handles pen-registers and trap-and-traces, a type of surveillance that collects signaling information -- primarily the numbers dialed from a telephone -- but no communications content. (Pen registers record outgoing calls; trap-and-traces record incoming calls.)

DCS-6000, known as Digital Storm, captures and collects the content of phone calls and text messages for full wiretap orders.

A third, classified system, called DCS-5000, is used for wiretaps targeting spies or terrorists.

You can read more commentary from Ryan on Threat Level. Professors Matt Blaze and Steve Bellovin have also weighed in on the security implications of the system.

EFF obtained these documents through a FOIA lawsuit filed against the FBI last year. A federal judge has ordered [PDF] the Bureau to turn over new documents every month, so check back often the learn more about DCSNet.

As with all our FOIA documents, EFF encourages you to go through these files yourself and let the world know what you find. We ask only that you please mention EFF if you use these documents in any way. We're a nonprofit organization, and our funding for the FOIA Litigation for Accountable Government (FLAG) Project depends on showing that our work is important and relevant.

For more information about these documents or EFF's FLAG Project, please contact EFF Staff Attorney Marcia Hofmann at marcia(at)

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