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External BGP(eBGP): Network Layer Reachability Information (NLRI) is exchanged between network domain called Autonomous system usually administratively independant. We are speaking about BGP inter-domain routing. As an example, let's us aassume assume a BGP speaker from AS2200 (RENATER) advertising NLRI information to AS20965 (GÉANT R&E). From that point AS20965 has the knowledge of how to reach any network advertised by AS2200 based on the NLRI information.
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