[maxmouchet]

Bogus announcements are probably filtered by your upstream(s) (see [1] for a common list of filters).

IP-to-ASN mappings are typically built from route collectors [2,3] that peer with various networks and receive their announcements. AFAIK route collectors don't filter anything and it's easy to find bogus announcements (e.g. private ASNs) in the data.

I can't find 4294967296 from a quick glance at the latest RouteViews data but I can find other private ASNs. For example AS7594 - AS2764 - AS4294901866 for 210.10.189.0/24 seen by the route-views.perth collector.

I don't know what kind of filtering iptoasn.com is doing but at work (ipinfo.io) we do filter bogus origins, as well as a bunch of other things like RPKI/IRR-invalid routes and hyper-specific prefixes (> /24 or /48) [4].

[1] https://bgpfilterguide.nlnog.net

[2] https://www.routeviews.org/routeviews/

[3] https://www.ripe.net/analyse/internet-measurements/routing-i...

[4] https://hyperspecifics.io

[zamadatix]

Actually 4294967296 couldn't ever appear as the maximum value you can fit in the protocol field is 1 less than that... my problem here was I couldn't manage to keep the 2 numbers I was comparing (the one in the article and 2^32) straight haha! This was mistake was noted by a commenter here https://news.ycombinator.com/item?id=41963745

That said you're ultimately right that my upstream provider is filtering the 4294901866 value from the article as well anyways for the reasons you stated.

[maxmouchet]

Ah right haha. Thanks for the heads up, I should have checked ^^