Overview#Upstream Surveillance is a term used by the National Security Agency (NSA) of the United States for intercepting telephone and Internet traffic from the Internet backbone, i.e. major Internet cables and switches, both domestic and foreign.
Besides the Upstream Surveillance, NSA also gathers information from Internet communications through arrangements with Internet companies under the program codenamed PRISM. Both the Upstream Surveillance programs and PRISM are part of the Special Source Operations (SSO) division, which is responsible for collection in cooperation with corporate partners.
One of the slides of a presentation about the PRISM-program describes Upstream as "collection of communications on fiber cables and infrastructure as data flows past" and says the Upstream Surveillance is conducted under the following four major surveillance programs: