Xkeyscore - (NSA)

Xkeyscore - (NSA) computer system designed to search, retrieve and analyse global Internet data. Existence revealed by Edward Snowden in 2013. User Metrics are used to flag data, i.e. sex, ethnicity and geolocators. Worldwide, over 700 LINUX-based servers collect data for the system, using domestic and allied foreign partner agencies such as the UK's GCHQ. Various versions exist at different levels;

• Traditional; uses data from low-rate data systems first processed by WEALTHYCLUSTER. Used by NSA/GCHQ.
• Stage Two; used for higher data rates first processed by TURMOIL. Used by NSA/GCHQ MUSCULAR system.
• Deep Dive; used for data rates of ten gigabits p/second. Data filtered by GENESIS selection language. Used by NSA/GCHQ TEMPORA system. 

Xkeyscore is based - surprisingly - on Open Source software and recent concerns have emerged about it's own vulnerability to attack. 

Global Map of Xkeyscore server sites.