Telematics Chapter 6: Network Layer - Freie Universität Berlin

Border Gateway Protocol (BGP)
● Goal difference between internal and external protocols
● Interior gateway protocols are designed for efficiency
● Find the best way to the destination host
● Exterior gateway protocols have to consider policies
● Political, economical, …
● Border Gateway Protocol (BGP)
● BGPv4 (RFC 4271, RFC 4274, RFC 4276)
● De-facto standard inter-AS routing protocol in the Internet
● An external routing protocol
● Variant of the Distance Vector Protocol: not the costs of a transmission path are
being monitored and exchanged, but the complete description of paths (Path
Vector Protocol)
● Considers security and other rules (Routing Policies)
● Communicates the neighbor routers the whole path which is to be used
(deterministically)
● Uses TCP for data exchange (port 179)
Univ.-Prof. Dr.-Ing. Jochen H. Schiller ▪ cst.mi.fu-berlin.de ▪ Telematics ▪ Chapter 6: Network Layer
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