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:

• Filter-list with AS_PATH access-list.
• No-Export Community.
• Prefix-list Filtering
• Distribute-list Filtering

Links:

https://networklessons.com/bgp/bgp-prevent-transit-as

https://forum.networklessons.com/t/bgp-prevent-transit-as/1026/68?u=lagapides