Oi S.A. is an integrated telecommunications service provider in Brazil. The Company is a switched fixed-line telephony services (STFC) concessionaire. It is engaged in the provision of STFC as a local and intraregional long-distance carrier. Its segments include Residential Services, Personal Mobility, and SMEs/Corporate. It offers a range of integrated telecommunications services that include fixed and mobile, broadband, pay television (TV), data transmission and Internet provider services. The Company's Residential Services segment is focused on the sale of fixed telephony services, including voice services, data communication services (broadband), and pay TV. The Personal Mobility segment is focused on the sale of mobile telephony services to subscription and prepaid customers, and mobile broadband customer. The SMEs/Corporate segment includes corporate solutions offered to its small, medium-sized, and large corporate customers.