ASN to IP Mapping

Geoff Huston gih at
Sun Mar 8 00:16:07 UTC 2015

>> Is there a tool or method to determine IP blocks assigned to an
>> organization by ASN?  I.e. if I have an organization's ASN number I want to
>> know all blocks assigned to that ASN.

If you want to know the registry assignments / allocations made to a single entity and be able group together these assignments of address prefixes and ASNs you should retrieve the combined extended stats file from the RIRs  ( and group together all those entries with a common value in column 8 (except for the entries corresponding to assignments and allocations made by the RIPE NCC, where this information is, unfortunately, not published by them in such a convenient format.)



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