3com S7906E 설치 설명서
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BGP Configuration
The Border Gateway Protocol (BGP) is a dynamic inter-AS Exterior Gateway Protocol.
When configuring BGP, go to these sections for information you are interested in:
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The term “router” refers to a router or a Layer 3 switch, and BGP refers to BGP-4 in this document.
BGP Overview
There are three early BGP versions, BGP-1 (RFC1105), BGP-2 (RFC1163) and BGP-3 (RFC1267).
The current version in use is BGP-4 (RFC 4271), which is the defacto Internet exterior gateway protocol
used between ISPs.
The characteristics of BGP are as follows:
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Focusing on the control of route propagation and the selection of optimal routes rather than the
route discovery and calculation, which makes BGP, an exterior gateway protocol different from
interior gateway protocols such as OSPF and RIP
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Using TCP to enhance reliability
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Supporting CIDR
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Reducing bandwidth consumption by advertising only incremental updates and therefore
applicable to advertising a great amount of routing information on the Internet
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Eliminating routing loops completely by adding AS path information to BGP routes
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Providing abundant policies to implement flexible route filtering and selection
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Good scalability