NSA slides explain the PRISM data-collection program
Related NSA graphics
New slide published July 10
This slide shows PRISM as only one part of the NSA’s system for electronic eavesdropping. The "Upstream" program collects from the fiber-optic cable networks that carry much of the world’s Internet and phone data. The underlying map depicts the undersea cables that connect North America to the rest of the world.
Slides published June 29
Acquiring data from a new target
This slide describes what happens when an NSA analyst "tasks" the PRISM system for information about a new surveillance target. The request to add a new target is passed automatically to a supervisor who reviews the "selectors," or search terms. The supervisor must endorse the analyst's "reasonable belief," defined as 51 percent confidence, that the specified target is a foreign national who is overseas at the time of collection.
The FBI uses government equipment on private company property to retrieve matching information from a participating company, such as Microsoft or Yahoo and pass it without further review to the NSA.
For stored communications, but not for live surveillance, the FBI consults its own databases to make sure the selectors do not match known Americans.
This is where data enters NSA systems, described more fully on the next slide.
The Foreign Intelligence Surveillance Court does not review any individual collection request.
Analyzing information collected from private companies
After communications information is acquired, the data are processed and analyzed by specialized systems that handle voice, text, video and "digital network information" that includes the locations and unique device signatures of targets.
From the FBI's interception unit on the premises of private companies, the information is passed to one or more "customers" at the NSA, CIA or FBI.
PRINTAURA automates the traffic flow. SCISSORS and Protocol Exploitation sort data types for analysis in NUCLEON (voice), PINWALE (video), MAINWAY (call records) and MARINA (Internet records).
The systems identified as FALLOUT and CONVEYANCE appear to be a final layer of filtering to reduce the intake of information about Americans.
Each target is assigned a case notation
The PRISM case notation format reflects the availability, confirmed by The Post's reporting, of real-time surveillance as well as stored content.
Depending on the provider, the NSA may receive live notifications when a target logs on or sends an e-mail, or may monitor a voice, text or voice chat as it happens (noted on the first slide as "Surveillance").
Searching the PRISM database
On April 5, according to this slide, there were 117,675 active surveillance targets in PRISM's counterterrorism database. The slide does not show how many other Internet users, and among them how many Americans, have their communications collected "incidentally" during surveillance of those targets.
Original slides published June 6
Introducing the program
A slide briefing analysts at the National Security Agency about the program touts its effectiveness and features the logos of the companies involved.
The program is called PRISM, after the prisms used to split light, which is used to carry information on fiber-optic cables.
This note indicates that the program is the number one source of raw intelligence used for NSA analytic reports.
The seal of
Special Source Operations, the NSA term for alliances with trusted U.S. companies.
Monitoring a target's communication
This diagram shows how the bulk of the world’s electronic communications move through companies based in the United States.
Providers and data
The PRISM program collects a wide range of data from the nine companies, although the details vary by provider.
This slide shows when each company joined the program, with Microsoft being the first, on Sept. 11, 2007, and Apple the most recent, in October 2012.