any dangers of filtering every /24 on full internet table to preserve FIB space ?

Andrey Kostin ankost at
Fri Oct 14 12:47:24 UTC 2022

David Conrad писал(а) 2022-10-12 11:39:
> Andrey,
> There was a period in the mid- to late-90s where some of RIRs
> allocated longer than /24s, i.e., to match the amount of address space
> justified by the requester, even if that meant (say) a /29. This
> didn’t last very long as one of the (at the time) 800 lb gorillas
> (Sprint) decided to start filtering at /19 (which IIRC was the default
> prefix length RIPE-NCC chose to allocate to LIRs) to keep their
> routers from falling over.

I'm looking at it only from a practical side. I worked for different 
ISPs in RIPE region in 2000-s and never saw anything like that. There 
was a requirement from RIPE to create an object for any assigned /29 
subnet and larger for IP space usage documentation, but from allocated 
Anyways, even is it's true, it doesn't change anything. There are /24 PI 
blocks and if /24s are filtered, default route must be in use to have 
functional Internet connectivity.


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