ASN to IP Mapping

[rubensk at gmail.com (Rubens Kuhl)]

On Sat, Mar 7, 2015 at 12:37 PM, Andrew Iwamoto <
aiwamoto at unleashed-technologies.com> wrote:

> 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.
>

That's RIR/NIR-dependent, so you probably have to go thru all of them to
map all possible IP blocks. Other references suggested bgp.he.net that will
only list advertised networks, and IRRs will only have IRR-listed networks.

For instance, on ARIN for AS 15141:

http://whois.arin.net/rest/asn/AS15141

Find the organization name; click on the link
http://whois.arin.net/rest/org/BAUSCH-1.html

Find the networks link:
http://whois.arin.net/rest/org/BAUSCH-1/nets

Network ResourcesBAUSCH-LOMB (NET-161-242-0-0-1
<http://whois.arin.net/rest/net/NET-161-242-0-0-1.html>)161.242.0.0 -
161.242.255.255

Look for the other RIRs; rinse and repeat.



Rubens