BGP - preventing transit traffic

Transit traffic refers to network traffic that is passed through a network but is not originated or terminated within that network. Network infrastructure that belongs to ISPs is required to carry a certain amount of transit traffic based on specific rules and agreements.

In BGP topologies that are multihomed to two or more ISPs, there is a danger that an enterprise network may unwittingly and unwillingly be burdened with transit traffic if the appropriate precautions are not taken.

The primary methods of preventing unwanted transient traffic are: