2. BGP-IV protocol

2.1 General

The main function of a BGP-enabled router is to exchange IP network reachability information with other BGP-enabled routers. This information includes the list of ASes they have traversed, and is therefore sufficient to build a graph representing the connectivity of autonomous systems, from which it will be possible to avoid looping phenomena (which lead to the formation of "black holes" capable of rendering an IP network totally inoperative) and thanks to which it will be possible to implement routing policies defined by the administrator of an autonomous system.

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