Internet Routing Protocol Surasak Sanguanpong nguan@ku.ac.th - PDF document

1-1 Internet Routing Protocol Surasak Sanguanpong nguan@ku.ac.th http://www.cpe.ku.ac.th/~nguan/ Last update: July 30, 1999 http://www.cpe.ku.ac.th/~nguan  Applied Network Research Group, Department of Computer Engineering, Kasetsart University 1-2 Agenda � Basic concepts � Routing components � Classes of routing protocol http://www.cpe.ku.ac.th/~nguan  Applied Network Research Group, Department of Computer Engineering, Kasetsart University

1-3 Internet Routing Architecture Autonomous System EGP/BGP IGP EGP/BGP IGP IGP Autonomous BGP4 BGP4 Autonomous System System BGP4 IGP IGP Autonomous EGP/BGP EGP/BGP EGP/BGP EGP/BGP System IGP IGP IGP IGP Autonomous System http://www.cpe.ku.ac.th/~nguan  Applied Network Research Group, Department of Computer Engineering, Kasetsart University 1-4 Autonomous System � AS is a collection of LANs and WANs and the interconnecting routers which under the control of one management authority � The same AS runs the same Interior Gateway Protocol � Why setting up AS? - establish a direct link to each other rather than route through the core Internet � How to select AS? - register and get the AS number from NIC http://www.cpe.ku.ac.th/~nguan  Applied Network Research Group, Department of Computer Engineering, Kasetsart University

1-5 Gateway Protocol � Interior gateway protocol � exchange routing information between routers within a single AS � RIP, RIP II, OSPF � Exterior gateway protocol � collect network-reachablity information for the AS � EGP, BGP http://www.cpe.ku.ac.th/~nguan  Applied Network Research Group, Department of Computer Engineering, Kasetsart University 1-6 Routed and Routing Protocol � “tell neighbors about the my world” � “distance” means routing metric measured by hop count � “vector” means destination � flood routing table only to its neighbors � RIP is an example � also knowns as Bellmann-Ford algorithm or Ford-Fulkerson algorithm http://www.cpe.ku.ac.th/~nguan  Applied Network Research Group, Department of Computer Engineering, Kasetsart University