The Border Gateway Protocol (BGP) is an exterior routing or Inter-Domain Routing protocol used for exchanging routing information between autonomous systems. BGP is used for exchange of routing information between multiple transit autonomous systems as well as between transit and stub autonomous systems. BGP is related to EGP, but has more capability, greater flexibility, and less required bandwidth. BGP uses path attributes to provide more information about each route, and in particular to maintain an AS path, which includes the AS number of each autonomous system the route has transited, providing information sufficient to prevent routing loops in an arbitrary topology. Path attributes may also be used to distinguish between groups of routes to determine administrative preferences, allowing greater flexibility in determining route preference in order to achieve a variety of administrative ends.
BGP version-4 is being adapted to carry information on an Inter-Domain basis to support the Multicast protocols. GateD will support the use of Multiprotocol Extensions for BGP-4 for Multicast for IPv4 and IPv6.
This protocol implementation will only be available in GateD versions 4.2, 5 and 6. Support is anticipated by second quarter 1998. This documentation will provide the configuration for this use of the BGP-4 protocol.
Last updated November 29, 1997
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