nested prefixes in Internet
niels=nanog at bakker.net
Mon Nov 21 12:01:33 UTC 2016
* vas at mpeks.tomsk.su (Victor Sudakov) [Sun 20 Nov 2016, 03:07 CET]:
>I have reports that in case (2), some operators (e.g. Rostelecom)
>don't accept the /24 or even /23 prefix on the grounds that it is
>part of a larger /19 route already present in the routing table.
>Could they have a reason not to accept these more specific prefixes
>other than a whim?
If you announce a prefix you must deliver traffic sent to addresses
covered by it. You don't go announcing 0.0.0.0/0 to your peers either.
If a customer takes a /24 and announces it elsewhere, a transit
provider runs the risk of accepting inbound traffic without having
the possibility to bill their customer for it if it accepts more
specifics from e.g. a peer.
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