Re: IPv6 /64 links (was Re: ipv6 book recommendations?)

[Owen DeLong <owen () delong com>]

On Jun 6, 2012, at 1:02 PM, Steve Clark wrote:

> On 06/06/2012 03:05 PM, Owen DeLong wrote:
> > It is because of IEEE EUI-64 standard.
> >
> > It was believed at the time of IPv6 development that EUI-48 would run out of
> > numbers and IEEE had proposed going to EUI-64. While IEEE still hasn't
> > quite made that change (though Firewire does appear to use EUI-64 already),
> > it will likely occur prior to the EOL for IPv6.
> >
> > There is a simple algorithm used by IEEE for mapping EUI-48 onto the EUI-64
> > space.
> >
> > The 0x02 bit of the first octet of an EUI-64 address is an L-Flag, indicating that
> > the address was locally generated (if it is a 1) vs. IEEE/vendor assigned (if it is a 0).
> >
> > The mapping process takes the EUI-48 address XX:YY:ZZ:RR:SS:TT and maps
> > it as follows:
> >
> > let AA = XX xor 0x02.
> >
> > AAYY:ZZff:feRR:SSTT
> >
> > ff:fe above is literal.
> >
> > IPv6 was originally going to be a 32-bit address space, but, the developers
> did you mean "originally going to be a 64-bit address space"...

Uh, yeah... Sorry... Brain fart. Originally a 64-bit address space.


Owen