prefix filtering per IRR - practices

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1

Hi,

I have a question regarding what's the most common practice [1]
for transit ASs to filter prefixes from their BGP customers
when using IRR data. (which of course everyone does...)

Would many/most/all/none :
a) accept only the prefixes listed in route objects
or
b) accept these and anything "upto /24" (or "le 24")

I was hoping / assuming the latter but I start getting a different impression.
Yep, and apart from the current status, the tendency would be of interest.

Thanks,
Frank

[1] after "my network, my rules"

2

From my experience, networks that are capable of filtering from IRR objects

generally filter for exact routes, meaning no "le 24". While I've always
found networks to be set in their ways, I know some people that have
managed to get their filters changed to allow longer prefixes without
needing additional objects.

But ultimately, it does help prevent the leaking of internal routes.

-Chris

3

Le 22/11/2013 17:57, Chris Rogers a �crit :

From my experience, networks that are capable of filtering from IRR objects
generally filter for exact routes, meaning no "le 24".

Hi,

Are you sure? My experience is, with a small number of exceptions,
that "le 24" ('route' or 'route-set,' sometimes in relation with "is in
AS-set of peer") is an often used policy. Maybe it depends on what
kind of networks one's looking at?

Cheers,
mh