[ppml] IPv6, Vista, and the Popular Press [more]

Durand, Alain Alain_Durand at cable.comcast.com
Mon Jun 11 21:38:42 EDT 2007

> >From what I understand from that book, the original IPv6 
> addressing was
> 64 bits in size. However, to allow for deriving node 
> addresses from IEEE MAC addresses, and allowing for those to 
> be increased from 48 to
> 64 bits, the decision was made to make the node address 
> portion of the address 64 bites, and then to make the network 
> portion also 64 bits.

The 64 bit EUI came much later, at about the same time as 8+8...
Steve Deering always told me that his original design was 64 bits as
you can read in the original SIP proposal (SIP: Steve's IP)
There was at the time disagreement between the proponent of variable
length addresses (NSAP) and fixed length address.
When SIP and PIP (Paul's IP from Paul Francis) were merged into
SIPP (SIP Plus), the compromise was to use a 'long' fixed format,
hence 128 bits.

   - Alain.

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