In message <20141121090850.GP28745@Space.Net>, Gert Doering <gert@space.net> wrote:
To state something that might be obvious or not - for the same prefix, you can have multiple route: entries with different origin ASes...
Yes. Thank you. So I have now been informed. I do confess, freely, that I had not considered or anticipated such a possibility at all when I performed my simple minded analysis, and also must admit that had the small script I write to perform this analysis properly taken into account the meaning of such cases, the number I reported would have been different, probably with a lower number of "anomalies" (although, I suspect, not too much lower). Regarding the _use_ of the RIPE data base odf route objects, you wrote:
We use it to build BGP filters for BGP customers. ... (Our upstream providers do the same thing for us, so it's used on a larger scale...
It is, at once, both comforting to know that some folks, at least, are indeed making use of this data (RIPE IRR) to try to prevent bogus route announcements from leaking out, but also a bit worrying that the data seems to contain so many anomalies. Regards, rfg