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Re: [74attendees] The great emphasis on IPv6 - a positive look



Philip Homburg wrote:
> In your letter dated Sat, 28 Mar 2009 11:38:42 +0100 you wrote:
>> And import the complete IPv4 routing table into the IPv6 routing table.
>> No thank you.
> 
> No, instead of that, every ISP gets a completely new prefix, wastes a lot of
> bits in that prefix (you need 32 bits for the IPv4 address),

6rd does NOT require that. Did you read Remi's draft? If an ISP has a
IPv4 /21 for their customers they want to IPv6 enable then they need
32-21 = 11 bits. Thus they need a /48 - 11 = /37 for their 6rd prefix.
Then every user gets a nice /48. Or what Free does, give a /56 which is
'good enough for endusers' and thus you only need a /56 - 11 = /45.
If they ISP has 5 IPv4 /21s they thus need 5x /45 for this trick.

That address space can later, when the users get real native v6 (if
ever) be re-allocated for other things.

Still only 1 /32 (or larger if the ISP was able to justify that) will be
visible in the IPv6 routing tables. Instead of 5 6to4 prefixes which
should not be there in the first place.

> and then adds it to the routing table. And you can't even give customers
> the /48 they are supposed to get.
> 
>> Fortunately 2002::/16 orlonger is pretty well filtered.
> 
> You are saying that if an ISP gets a /32 from a RIR it is no problem, but a
> 2002::xxyy/32 suddenly is a problem?

Yes, as that is what the RFC specifies. As I wrote in my previous email
(and thus still a few lines above here) to avoid importing the IPv4
routing tables into IPv6. IPv6 != IPv4.


Please actually read the 6to4 RFC and the 6rd draft.

Greets,
 Jeroen

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