On Sep 18, 2019, at 6:34 PM, Anurag Bhatia <me@anuragbhatia.com> wrote:
Hello everyone
Trying to understand the case from operators here who generate IRR based filters.
Say if a given example:
AS X originating 2001:DB8::/32 with IRR route object having AS X in the origin AS X originating 2001:DB8::/48 with IRR route object having AS Y in the origin
Now for folks who are generating filters, will your tools filter 2001:DB8::/48 because there's a more specific IRR route object which says AS Y while prefix is coming from AS X? Or since generation is based on ASNs (as known directly or resolved via AS SETs) your tools will just generate filter for AS X allowing 2001:DB8::/32 (upto say /48) and won't really for mismatching route object for 2001:DB8::/48?
Generally you might build the filters one of two ways: 1) with just the ASN, eg: 267 where you would build just with that origin ASN. 2) with the AS-SET, eg: AS-NETHER This includes 2 ASNs (but could also include other things, eg: AS-AKAMAI) and those are also expanded. - Jared