Usenet Service Provider Data Connections
Peers in newsgroups, as with peers in general, are relationships established between two or more parties for the mutual benefit of each other. A newsgroup peer is usually between two ISP’s or news services, for the purpose of exchanging traffic directly, rather than doing so through a backbone Internet provider.
Traditionally, that traffic was exchanged at no cost, although that no longer is necessarily true. Usually, most peering relationships are set up by having the amount sent between two peers be as equal as possible. Basically this means that the amount I send you should be the amount that you send me. Peering at Fastusenet.org works this way. Many of our peers run their service in a similar fashion.
Data Peering Between Usenet Providers
The relationship a Usenet Service Provider has with its peers is vital to the survival and the success of a news service because that is where they get the information. A news service will have many peers and not rely on the feed from one peer solely.
The more peers a provider has, the better completion you can expect as there will be a greater variety and number of articles coming in to its servers. The feed from just one news service will only be from what that peer has and if they don’t carry all of the groups that you do, then there will be missing groups.