FW: /8s and filtering

N nathan at stonekitty.net
Tue Dec 10 21:11:52 UTC 2002

On Tue, Dec 10, 2002 at 12:45:42PM -0800, Harsha Narayan wrote:
> > 	2) Small multihomers must get the ISP that assigns them address space to
> > allocate them at least a /24 (with multihoming as the justification if
> > needed). The ISP must agree to allow them to advertise their allocation
> > through other providers and must agree to hear and announce the block from
> > the customer *and* *other* *ISPs*.
> >
> Hello,
> Doesn't this mean that unless filtering policies change, after Class C
> space is used up, the multihomer will have to get a /22 from the ISP
> (since after Class C gets used up allocations will be made from Class A
> space). There are only three /8s left in the Class C space.

To be accepted into Verio's space per the URL that
forrest at almighty.c64.org pasted... you are correct.  I still think this
is a rare method of filtering... and perhaps Verio will change their
policy to be /24 everywhere once the Classfull C ranges are gone. As
others have mentioned... not all providers filter in the same way, and
sometimes the methods are not published..... Its relatively safe to
make a *vague* judgement that a /24 will get you reachable via *most* of 
the net.  

~Nathan - routing & switching dude/fly-boy/sport biker - San Jose CA~

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