Abstract
Despite the architectural separation between intradomain and inter-domain routing in the Internet, intradomain protocols do influence the path-selection process in the Border Gateway Protocol (BGP). When choosing between multiple equally-good BGP routes, a router selects the one with the closest egress point, based on the intradomain path cost. Under such hot-potato routing, an intradomain event can trigger BGP routing changes. To characterize the influence of hot-potato routing, we conduct controlled experiments with a commercial router. Then, we propose a technique for associating BGP routing changes with events visible in the intradomain protocol, and apply our algorithm to AT&T's backbone network. We show that (i) hot-potato routing can be a significant source of BGP updates, (ii) BGP updates can lag 60 seconds or more behind the intradomain event, (iii) the number of BGP path changes triggered by hot-potato routing has a nearly uniform distribution across destination prefixes, and (iv) the fraction of BGP messages triggered by intradomain changes varies significantly across time and router locations. We show that hot-potato routing changes lead to longer delays in forwarding-plane convergence, shifts in the flow of traffic to neighboring domains, extra externally-visible BGP update messages, and inaccuracies in Internet performance measurements.
Original language | English (US) |
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Pages (from-to) | 307-318 |
Number of pages | 12 |
Journal | Performance Evaluation Review |
Volume | 32 |
Issue number | 1 |
DOIs | |
State | Published - 2004 |
Event | SIGMETRICS 2004/Performance 2004: Joint International Conference on Measurement and Modeling of Computer Systems - New York, NY, United States Duration: Jun 12 2004 → Jun 16 2004 |
All Science Journal Classification (ASJC) codes
- Software
- Hardware and Architecture
- Computer Networks and Communications
Keywords
- BGP
- Convergence
- Hot-potato routing
- OSPF