Telecom Regulatory Authority of India and the tribunal that took over its disputes work

The entry of private service providers brought with it the need for independent regulation of telecom services.
The Telecom Regulatory Authority of India (TRAI) was established with effect from 20th February 1997 by an Act of Parliament, called the Telecom Regulatory Authority of India Act, 1997.
TRAI regulates telecom services, including fixation and revision of tariffs for telecom services, which were earlier vested in the Central Government.
TRAI has issued a large number of regulations, orders and directives covering tariff, interconnection, quality of service and the governance of the Authority.
The TRAI Act was amended by an ordinance, effective from 24 January 2000, establishing a Telecommunications Dispute Settlement and Appellate Tribunal (TDSAT) to take over the adjudicatory and disputes functions from TRAI.
TDSAT adjudicates disputes between a licensor and a licensee, between two or more service providers, and between a service provider and a group of consumers.
TDSAT also hears and disposes of appeals against any direction, decision or order of TRAI.

TRAI established with effect from: 20th February 1997 Founding Act: Telecom Regulatory Authority of India Act, 1997 TDSAT created with effect from: 24 January 2000 Function moved to TDSAT: Adjudicatory and disputes functions
Why it matters for exams: TRAI's founding Act and the split of its adjudicatory work to TDSAT are a standard regulator-versus-tribunal question.
Kerala PSCUPSCBank

In plain words

TRAI Telecom Regulatory Authority of India — The statutory regulator for telecom and broadcasting tariffs and quality of service.

TDSAT Telecommunications Dispute Settlement and Appellate Tribunal — Hears telecom disputes and appeals against TRAI's orders.

Interconnection Linking of one operator's network with another's — One of the subjects TRAI regulates by order and regulation.