Sasse spells it out crystal clear for the people
Ties in to what Q been saying.
Solving the mystery of PRISM
Now, these accounts are being updated in real-time. So Facebook somehow creates a mirror of the slice of stuff that only the NSA can access. The selected/court-ordered accounts are updated in real-time on both the Facebook server and the mirrored server. PRISM is the tool that puts this all together. Facebook has no idea what the NSA is doing with the data, and the NSA doesn't tell them.
There are many types of nicknames and special words that the NSA uses.
Some refer to collection tools. Some refer to data processing tools.
Each data processing tool, collection platform, mission and source for raw intelligence is given a specific numeric signals activity/address designator, or a SIGAD. The NSA listening post at Osan in Korea has the SIGAD USA-31. Clark Air Force Base is USA-57.
PRISM is US-984XN
SENIOR SPAN platform, attached to U2 spy planes, is known as G112
The agency's Special Collection Service, which operates out of embassies, is F6
"Marina" is a database for metadata collected from telephone records. Marina=telephone metadata — classified. Marina by itself … unclassified.
MAUI is a database for finished NSA intelligence products.
Anchory is an intelligence community-wide database for intelligence reports.
A system called XKEYSCORE processes most of the SIGINT traffic that comes into the NSA by way of various SIGADs, and compartmentalizes it by selector. A selector might be "RUSFOR," which would stand for Russian foreign ministry intercepts. Or something like that. Recorded signals intercepts are stored in a database called PINWALE.
https://theweek.com/articles/463418/solving-mystery-prism
The chain of action works like this.
Under the FISA Amendments Act of 2008, the NSA and the attorney general apply for an order allowing them to access a slice of the stuff that a company like Facebook keeps on its servers. Maybe this order is for all Facebook accounts opened up in Abbottabad, Pakistan. Maybe there are 50 of them. Facebook gets this order.
Now, these accounts are being updated in real-time. So Facebook somehow creates a mirror of the slice of stuff that only the NSA can access. The selected/court-ordered accounts are updated in real-time on both the Facebook server and the mirrored server. PRISM is the tool that puts this all together. Facebook has no idea what the NSA is doing with the data, and the NSA doesn't tell them.
https://theweek.com/articles/463418/solving-mystery-prism