IP to ASN

An IP address to autonomous-system lookup delivered through DNS.

ASNTeam Cymrunetwork operations

Screenshot used in the talk for IP to ASN — Screenshot used in the original talk.

Team Cymru’s DNS service maps an IP address to autonomous-system information. The query name represents the address, and the response provides routing data.

For network operators, this is faster to script than a conventional WHOIS lookup. It is one of the strongest practical examples in the collection.

Primary source: https://team-cymru.com/community-services/ip-asn-mapping/#dns