A unique and unusually productive relationship with AT&T has helped the US National Security Agency trawl through vast quantities of Internet traffic, much of it transmitted through networks located in the US, according to a media article published Saturday.

The cooperation involved a variety of classified programs that span decades, in one case more than 15 years before the September 11 terrorist attacks. In addition to providing the NSA with access to billions of e-mails flowing across its domestic networks, AT&T helped wiretap all Internet communications at the United Nations headquarters, which is, or at least was, an AT&T customer, according to the article, which was jointly reported and written by reporters from The New York Times and ProPublica. The article, which relied on NSA documents leaked by former agency contractor Edward Snowden, said that AT&T competitor Verizon participated in some of the same activities, but on a much smaller scale. One NSA document reminded officials to be polite when visiting AT&T sites since the arrangement was a “partnership, not a contractual relationship.”

One of the oldest programs is dubbed Fairview and began in 1985. A separate program known as Stormbrew included Verizon and MCI, the former telecommunications provider that Verizon acquired in 2006. The NYT and ProPublica go on to paint AT&T as a particularly willing partner. The article stated: