Telephones of Mexico S.A.B. de C.V. (Telmex) is a provider of telecommunications and information technology, subsidiary of Mexican América Móvil. The company offers connectivity, Internet access and interconnection services in Mexico. It operates a copper and fiber optic network for voice and data services. In addition, it has transmission equipment, radio frequency systems, submarine cables, switching centers and offices distributed throughout Mexico. It was founded in 1947 and is headquartered in Mexico City.