On the Characteristics of BGP Multiple Origin AS (MOAS) Conflicts

The Internet consists of thousands of autonomous systems (ASs), each advertising one or more prefixes it has connectivity to. According to RFC 1930, each prefix should originate from a single AS. However, more than one ASs may advertise reachability to a given prefix, so called multiple origin AS conflict (MOAS). To this end, this paper analyzes and quantifies MOAS conflicts from a dataset consisting of routing updates collected over 21 days in January, 2007, and presents ten scenarios that lead to MOAS conflicts.
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