[nsp] Typical Prefix filters - greater than /24's dropped?

Gert Doering gert at greenie.muc.de
Thu Nov 20 16:29:36 EST 2003


On Thu, Nov 20, 2003 at 10:58:48AM -0000, Sam Stickland wrote:
> I'm trying to get a feel for the sort of prefix filters that are typically
> in use on the backbones and transit providers. Are prefixes longer than
> /24's typically filtered out?

We do not accept anything more-specific than a /24.

I'd really appreciate if people would stick to aggregation: announce your
network block in *one* piece.  Don't try to impose the costs for your
broken business models ("this upstream must only be used for backup, so
I'll announce more-specific over the other upstream") onto the whole

*Everybody* pays for every additional prefix, and it sums up.  When we hit
200.000 routes (or so), the next round of "junk all your backbone ciscos
because they can't take more than 256 Mb of RAM" is due, and then you'll
*feel* the cost.  Stop it before that happens.

USENET is *not* the non-clickable part of WWW!
Gert Doering - Munich, Germany                             gert at greenie.muc.de
fax: +49-89-35655025                        gert at net.informatik.tu-muenchen.de

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