North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: v6 subnet size for DSL & leased line customers
On Fri, 28 Dec 2007 12:57:45 +0900 Randy Bush <[email protected]> wrote: > > Ever calculated how many Ethernet nodes you can attach to a single LAN > > with 2^46 unicast addresses? > > you mean operationally successfully, or just for marketing glossies? > Theoretically. What I find a bit hard to understand is peoples' seemingly complete acceptance of the 'gross' amount of ethernet address space there is available with 46 bits available for unicast addressing on a single LAN segment, yet confusion and struggle over the allocation of additional IPv6 bits addressing bits for the same purpose - the operational convenience of having addressing "work out of the box" or be simpler to understand and easier to work with. Once I realised that IPv6's fixed sized node addressing model was similar to Ethernet's, I then started wondering why Ethernet was like it was - and then found a paper that explains it : "48-bit Absolute Internet and Ethernet Host Numbers" http://ethernethistory.typepad.com/papers/HostNumbers.pdf Regards, Mark. -- "Sheep are slow and tasty, and therefore must remain constantly alert." - Bruce Schneier, "Beyond Fear"
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