What is the most standard subnet length on internet

Grzegorz Janoszka Grzegorz at Janoszka.pl
Tue Dec 23 07:49:00 CST 2008


Nathan Ward wrote:
>>> Let me rephrase; Are there people who are filtering /24s received from
>>> eBGP peers who do not have a default route?
>>
>> of course.
> 
> Curiously, it was really meant as a rhetorical question where the answer 
> was "no".
> 
> Why are people doing this? Are they lacking clue, or, is there some 
> reasonable purpose?

Memory mostly I think. /24 prefixes are ~ the half of all prefixes, but 
they cover only a small percent of the address space.
If your router has > 6 full BGP sessions, you can filter /24 on half of 
them, your memory usage will drop significantly.

-- 
Grzegorz Janoszka
Leaseweb




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