The Swiss telegraph network was first set up in 1852, followed by telephones in 1877. The two networks were combined with the postal service in 1920 to form the PTT (Postal Telegraph and Telephone). It struggled to develop a homegrown digital network, with the first digital exchange launched in 1986, but pioneered the NATEL A mobile service in 1978 and the GSM-based NATEL D offering a digital service in 1993. The Swiss telecommunications market was deregulated in 1997. Telecom PTT was spun off and rebranded Swisscom ahead of a partial privatisation in 1997. The present-day Swisscom owns the protected brand NATEL, which is used and known only in Switzerland.