Every country is connected with each other directly or indirectly with the help of submarine fiber optics cables to get access to the Internet. The main job of Tier 1 ISPs is to connect the 2 or more countries’ landmasses using fiber optics cable.
In India, we are connected to the world internet from Chennai, Cochin, Mumbai, Trivandrum, and Tuticorin IXP (Internet Exchange Point). IXP is an infrastructure like an office through which ISP (Internet Service Provider) and CDN (Content Delivery Networks) exchange Internet traffic between their networks.
Tier 1 ISP handles the connectivity between 2 or more countries and they are the ultimate reasons we are accessing the internet today.
Anyhow if the submarine cable gets cut or damaged by any reason (common reasons are shark attack and anchor drops), we can lose partial or complete connectivity that depends on the availability of other Tier 1 ISPs.
In India, we have following telecommunication companies which are tier 1 ISPs.
|No.||Tier 1 ISP||Landing Stations||Cables|
|1||Tata Communications||Chennai (1), Cochin (1), Mumbai (3).||7|
|2||Bharti Airtel||Chennai (2), Mumbai (1).||5|
|3||Reliance Jio Infocomm Limited||Chennai (1), Mumbai (1).|
India Asia Xpress (IAX).
India Europe Xpress (IEX).
|4||Global Cloud Exchange||Mumbai (1), Trivandrum (1).||3|
|6||Sify Technologies||Mumbai (1).||1|
|8||IOX||Puducherry (1) under construction.||1|
Whoever wants to connect with them (mostly data centers and tier 2 ISPs) can buy bandwidth from them. Many data centers also have a direct connection or peering with them to decrease their worldwide latencies.
In India, we have NIXI (National Internet Exchange of India), a non-profit company incorporated under Section 25 of the India Companies Act, 1956 with the objective of facilitating improved internet services in the country.
The main job of NIXI is to facilitate the exchange of domestic internet traffic between the peering networks, content players, and any other organizations with their own AS (Autonomous System) number by enabling more efficient use of international bandwidth, saving foreign exchange, and also improves the Quality of Services (QoS) for Internet users by avoiding multiple international hops and thus reducing latency.
It means if you are accessing a locally hosted site then your network request will never leave India, instead, it will route your request to the shortest found way inside India from various available networks in India. This saves cost and time.
So this is everything about tier 1 ISPs in India.