A View of the AS Hierarchy Provider - customer

A View of the AS Hierarchy No transitivity No SP concatenation Provider - customerData path

A View of the AS Hierarchy Provider - customerData pathPeer to peer

4 BGP Operations (Simplified) Establish session on TCP port 179 Exchange all active routes Exchange incremental updates AS1 AS2 While connection is ALIVE exchange route UPDATE messages BGP session

5 Two Types of BGP Neighbor Relationships External Neighbor (eBGP) in a different Autonomous Systems Internal Neighbor (iBGP) in the same Autonomous System AS1 AS2 eBGP iBGP iBGP is routed (using IGP!)

Home Assignment Shortest Path algorithm The input graph: Lines of the format An EOF indication, e.g.: 0 Where: :- integer :- C-P1 P-C2 P2P3 sibling4 The program: Reads v and u and outputs a shortest path from v to u with BGP constraints Please print the program code and an example execution. A test case will be placed in the course web site