ASN to IP Mapping

Hank Nussbacher hank at
Sun Mar 8 07:35:58 UTC 2015

At 14:37 08/03/2015 +1100, Geoff Huston wrote:

> > On 8 Mar 2015, at 1:39 pm, Randy Bush <randy at> wrote:
> >
> >> 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.)
> >
> > care to give a decode for the fields in that file?  :)
>sure, I'll try.



>for example:
>Col 1 - RIR name, or 'iana'
>Col 2 - The country where the entity 'resides' (or 'EU' in some cases), or 
>'ZZ' for reserved and unassigned blocks
>Col 3 - 'asn' or 'ipv4' or 'ipv6'
>Col 4 - The size of the allocation (asn or IPv4) or the prefix length (ipv6)
>Col 5 - The starting value of the block
>Col 6 - A date. For some registries this is the date of the original 
>allocation - for others (ARIN) its not so clear precisely what this date 
>signifies (!)
>Col 7 - Status of the block
>Col 8 - A hash field of the entity code (mu;ltiple allocations to the same 
>entity have the same code) or null (RIPE NCC, IANA)
>Col 9 - The source of the record (either "e-stats' where the original 
>source is an extended stats file published by an RIR, or 'iana' if the 
>data is lifted from an IANA registry)

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