Route Oracle: Where Have All the Packets Gone?

Date Added: Feb 2010
Format: PDF

Many network-management problems in large backbone networks need the answer to a seemingly simple question: Where does a given IP packet, entering the network at a particular place and time, leave the network to continue on its path to the destination? Answering this question at scale and in real time is challenging for several reasons: A destination IP address could match several IP prefixes, the longest-matching prefix may change over time, the number of IP prefixes and routing protocol messages is very large, and network-management applications often require answers to this question for a large number of destination IP addresses in real time.