BGP Attributes and Path Selection

Hello Manami

Address Family Indicator (AFI) and Subsequent Address Family Indicator (SAFI) are fields within Multi-Protocol BGP (MP-BGP) extensions. The information in these fields is sent as part of the neighbor capability exchange during the process of becoming BGP peers. The information in these fields is used to tell the remote peer what address family (IPv4, IPv6, VPNv4, VPNv6 etc.) and what specific sub-address family (multicast or unicast) the local BGP router will be transporting routes for.

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