An Internet service provider (ISP) is an organization that provides access to the Internet.
Internet service providers can be either community-owned and non-profit, or privately owned and for-profit.
Access ISPs directly connect clients to the Internet using copper wires, wireless or fiber-optic connections. Hosting ISPs lease server space for smaller businesses and other people (colocation). Transit ISPs provide large amounts of bandwidth for connecting hosting ISPs to access ISPs.
There are 3 tiers:
- Tier 1: a tier 1 network is one that can reach every other network on the Internet without purchasing IP transit or paying settlements.
- Tier 2: a tier that can access some part of the network without paying transit
- Tier 3: only uses transit