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Telecom networks, spectrum and internet infrastructure

Telecom networks and the physical internet: mobile generations and spectrum, telecom law and its regulator, rural broadband, fibre, subsea cables and their landing stations, and the rules of the net. It serves GS3 answers on infrastructure and communications.

Showing 4 of 4 subjects, those that changed from 1 July to 15 September 2026.Show all

Prelims

A country's link to the rest of the internet is physical, and narrower than it looks: a few fibre cables lying on the seabed, each of which has to come ashore somewhere. Those few coastal points are where its entire international capacity is concentrated.

  • Almost all traffic between countries travels on subsea cables rather than by satellite.
  • A cable comes ashore at a cable landing station, which joins it to the domestic network.
  • Data centres cluster near a landing station, because content stored close to the cable reaches users with the least delay.

What changed

  1. 28 Aug 2026

    The Hindu, 28 Aug 2026: Andhra set to emerge as third subsea hub following datacentre buildout (opens in a new tab)

  2. 28 Aug 2026

    • Most of the cables on India's east coast are old and nearly full, and instability in West Asia is pushing operators towards routes that avoid it.
    • The 3,600 km India and Southeast Asia (I-2SEA) system is expected to land at Visakhapatnam and be ready for service by late 2029.
    • Google's America India Connect is the other system planned for the same landing.
    • Andhra Pradesh's data centre buildout came first, and the new cables are following it to the coast.

    The Hindu, 28 Aug 2026: Andhra set to emerge as third subsea hub following datacentre buildout (opens in a new tab)

Prelims and Mains

Bharat 6G is India's programme for the sixth generation of mobile technology, with a spectrum roadmap, a terahertz testbed and an alliance of research and industry bodies, working within the International Telecommunication Union's IMT-2030 framework.

What changed

  1. 28 Jul 2026New subject

    • The Department of Telecommunications released a spectrum roadmap for 6G, and a terahertz testbed is being built at the Society for Applied Microwave Electronics Engineering and Research (SAMEER), Kolkata with three IITs.
    • India secured ubiquitous connectivity as one of the six usage scenarios of IMT-2030, the International Telecommunication Union's framework for 6G.
    • The Bharat 6G Alliance has 90 member organisations.

    PIB, 28 Jul 2026: Government Reiterates Commitment to Making India a Global Leader in 6G Technologies (opens in a new tab) · PIB, 22 Jul 2026: Bharat 6G Alliance and Spectrum Roadmap for 6G in India (opens in a new tab)

Commercial call number series

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Prelims

The 1600 number series is reserved for service calls from regulated financial entities and government, and the 140 series for promotional calls, so that a subscriber can tell one from the other and block the second.

What changed

  1. 10 Jul 2026New subjectalso in news

    • The 1600 series is reserved for service calls from regulated financial entities and government, and may not be tagged or filtered. The 140 series is for promotional calls, which a subscriber can block only through the Do Not Disturb registry.

    PIB, 10 Jul 2026: TRAI releases clarifications regarding functioning of designated 1600 series and 140 series (opens in a new tab)

Intra circle roaming in disasters

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Prelims

Intra circle roaming lets a subscriber use whichever operator's network still works within the same telecom circle, and is switched on by direction of the Department of Telecommunications after a disaster.

What changed

  1. 24 Jul 2026New subjectalso in news

    • After floods and landslides, operators were directed to let any subscriber use whichever network still works within the same telecom circle, in parts of Jammu and Kashmir, Assam, Nagaland and Gujarat.

    PIB, 24 Jul 2026: Swift measures taken to ensure uninterrupted telecom connectivity and support emergency operations across disaster-affected region (opens in a new tab) · PIB, 23 Jul 2026: Measure Aimed at Ensuring Uninterrupted Telecom Connectivity during Disaster Situation (opens in a new tab)