ENCORE: A diagnostic system for inter-AS routing anomalies

If the Internet is operated reliably to ensure stable access, it is important to verify whether the routing information originated from an autonomous system (AS) is correctly spread throughout the Internet as the AS intends. Because the routing information changes as it spreads, it is necessary to observe the routing information from outside the AS. Each AS is controlled by a single administrative authority based on that AS's own policy, so a cooperative distributed solution is desirable. To cope with these requirements, we have proposed a multiagent-based inter-AS diagnostic system called ENCORE, where a collection of intelligent agents are located in multiple ASs and perform collective observation and analysis. This paper describes its diagnostic model and functions by focusing on agents' cooperative actions, and discusses the effectiveness and limitations of ENCORE.