Internet Service Provider (ISP) hierarchy

Internet Service Provider (ISP) is a company which provides internet connection to end user, but there are basically three levels of ISP. There are 3 levels of Internet Service Provider (ISP): Tier-1 ISP, Tier-2 ISP, and Tier-3 ISP.

These are explained as following below.

  1. Tier-1 ISP:
    These ISPs are at the top of the hierarchy and they have a global reach they do not pay for any internet traffic through there network instead lower-tier ISPs have to pay a cost for passing there traffic from one geolocation to another which is not under the reach of that ISPs. Generally, ISPs at the same level connect to each other and make allow free traffic passes for each other these ISPs are called peers. Due to this cost is saved. They build infrastructure, such as the Atlantic Internet sea cables, to provide traffic to all other Internet providers, not end users.

    Some examples of tier 1 Internet providers:

    Cogent Communications,
    Hibernia Networks,

  2. Tier-2 ISP:
    These ISPs is a service provider who connects between tier 1 and tier 3 ISPs. They have regional or country reach and behave just like Tier-1 ISP for Tier-3 ISP.

    Examples of tier 2 ISPs:

    British Telekom 

  3. Tier-3 ISP:
    These ISPs are closest to the end users and helps them to connect to the internet by charging some amount. These ISPs work on purchasing model. These ISPs have to pay some cost to Tier-2 ISPs based on traffic generated.

    Examples of Tier-3 ISPs:

    Deutsche Telekom.
    Verizon Communications 

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready.

My Personal Notes arrow_drop_up

Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using or mail your article to See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.

Article Tags :
Practice Tags :


Please write to us at to report any issue with the above content.