Mark Baker spake unto us the following wisdom:
> > As there are no huge technical or address allocational reasons why ISP's
> > could not give at least /64, those ISP's that do get more popular and ones
> > dealing /128's do not, and disappear from IPv6 market.
> There are, however, technical reasons why ISPs might want to use dynamic IPs
> (if they have lots of dial-up hardware in different locations, routing
> issues make static IP difficult), so although their customers would get a
> /64, it might be a different one every time they dial up.
> In that situation, since I wouldn't want addresses on my local network to
> keep changing, I would want to use NAT to translate the address block
> assigned by the ISP onto some site local address space.
IIRC, there are discussions in one of the IPv6 RFCs of exactly this.
This type of NAT is obscenely simple for protocols that are not
internally address-aware (i.e. not FTP, DCC, etc.), as you simply
replace the top N bits (where N is your prefixlen) and adjust the
TCP/UDP checksum as necessary.
'Fraid I can't help for address-aware protocols, but the salient point
here is that that type of NAT is officially blessed somewhere, I
If I've told you once, I've told you once
And once is all that you needed.
-- The Refreshments, "Carefree"
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