Reading Room Document

Use of the EINSTEIN 2.0 Intrusion-Detection System to Protect Unclassified Computer Networks in the Executive Branch

An intrusion-detection system known as EINSTEIN 2.0 used to protect civilian unclassified networks in the Executive Branch against malicious network activity complies with the Fourth Amendment to the Constitution, the Wiretap Act, the Foreign Intelligence Surveillance Act, the Stored Communications Act, and the pen-register and trap-and-trace provisions of 18 U.S.C. § 3121 et seq., provided that certain log-on banners or computer-user agreements are consistently adopted, implemented, and enforced by executive departments and agencies using the system. The OLC does not provide release dates for its opinions, so the release date listed is the date on which the opinion was authored. The original opinion is available at www.justice.gov/olc/file/2009-01-09-einstein/download.

January 9, 2009