Correct Answer - Option 3 : ISP
The national Internet service providers are backbone networks created and maintained by specialized companies. To provide connectivity between the end users, these back-bone networks are connected by complex switching stations (normally run by a third party) called network access points.
Internet service providers are categorized as:
International Service Providers: At the top of the hierarchy are the international service providers that connect nations together.
National Service Providers:
- The national Internet service providers are backbone networks created and maintained by specialized companies.
- To provide connectivity between the end-users, these backbone networks are connected by complex switching stations (normally run by a third party) called network access points (NAPs).
- Some national ISP networks are also connected to one another by private switching stations called peering points. These normally operate at a high data rate.
Regional Service Providers:
- Regional internet service providers or regional ISPs are smaller ISPs that are connected to one or more national ISPs.
- They are at the third level of the hierarchy with a smaller data rate.
Local Service Providers:
- Local Internet service providers provide direct service to the end-users.
- The local ISPs can be connected to regional ISPs or directly to national ISPs.
- Most end-users are connected to the local ISPs
BSNL, Reliance, Shaw cable, AOL, Tata Indicom all come under the category of Internet service providers.
