What is an Internet Service Provider (ISP)?

An Internet Service Provider (ISP) can also be known as an Internet Access Provider (IAP), and is a business or organisation which offers various technical services that are required to use or operate internet services.

ISP’s can be started by anyone with sufficient money and expertise, whether they are an individual or a business. This is different from how it was in the past, when most ISP’s were run by the phone companies.

In addition to internet access via various technologies such as broadband, dial-up and DSL, they may also provide a combination of services which include internet transit, domain name registration and hosting, web hosting and colocation.

How do ISP’s connect to the internet?

ISP’s pay upstream ISP’s for internet access. The ISP then uses this connection to send or receive any data to or from parts of the internet which are beyond its own network.

The upstream ISP then uses its own upstream connection, or connections to its other customers (usually other ISP’s), to allow the data to travel from source to destination.

However, the situation is often more complicated in reality. ISP’s with more than one point of presence (PoP), which means more than one access point to the internet, may have separate connections to an upstream ISP at multiple PoP’s.

They could also be customers of multiple upstream ISP’s and have connections to each one at one or more of their PoP’s.

What is a virtual ISP (vISP)?

With a virtual ISP (vISP), services from a wholesale ISP are purchased which allow the vISP’s customers to access the internet via one or more PoP that are owned and operated by the wholesale ISP.