A public data network (PDN) is a network established and operated by a telecommunications administration, or a recognized private operating agency, for the specific purpose of providing data transmission services for the public. The first network was deployed in 1972 in Spain called RETD. Public data network was the common name given to the international collection of X.25 providers whose combined network had large global coverage during the 1980s and into the 1990s, which provided infrastructure for the early Internet.