ASN to IP Mapping
gih at apnic.net
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 (https://www.nro.net/wp-content/uploads/apnic-uploads/delegated-extended) 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.)
More information about the NANOG