Singapore Telecommunications Limited (commonly abbreviated as Singtel, and previously stylised as SingTel) is a Singaporean telecommunications company. The company is the largest mobile network operators in Singapore with 4.1 million subscribers and through subsidiaries, has a combined mobile subscriber base of 640 million customers at the end of financial year 2017. The company was known as Telecommunications Equipment until 1995. Singtel provides ISP (SingNet), IPTV (Singtel TV) and mobile phone networks (Singtel Mobile) and fixed line telephony services.

Sri Lanka Telecom PLC (SLT) is a telecommunications services provider in Sri Lanka and one of the country's largest companies(verification needed) with an annual turnover in excess of Rs 40 billion. The company provides domestic and corporate services which include fixed and wireless telephony, Internet access and IT services to domestic, public and business sector customers.

BT Group plc (trading as BT) is a holding company which owns British Telecommunications plc, a British multinational telecommunications company with head offices in London, United Kingdom. It has operations in around 180 countries and is the largest provider of fixed-line, mobile and broadband services in the UK, and also provides subscription television and IT services. BT’s origins date back to the founding of the Electric Telegraph Company in 1846 which developed a nationwide communications network. In 1912, the General Post Office, a government department, became the monopoly telecoms supplier in the United Kingdom.