The Choice: IPv4 Exhaustion or Transition to IPv6

Bora Akyol bora.akyol at
Thu Jun 28 21:54:22 UTC 2007

The length of the address (64 vs 128) is not the hard part. Just increases
the cost and the complexity of the ASIC ;-)

The extension headers become a real problem when L4 filtering is desired.


On 6/28/07 2:46 PM, "Valdis.Kletnieks at" <Valdis.Kletnieks at>

> On Thu, 28 Jun 2007 13:08:52 PDT, Bora Akyol said:
>> At a very low, hardware centric level, IPv6 would be a lot easier to
>> implement if
>> 1) The addresses were 64 bits instead of 128 bits.
>> 2) The extension headers architecture was completely revamped to be more
>> hardware friendly.
> Wow, a blast from the past.  The *current* IPv6 design was selected to a
> good extent because it was *easier* to do in hardware than some of the other
> contenders.  You think 64 versus 128 is tough - think about the ASIC fun and
> games to support *variable length* addresses (not necessarily even a multiple
> of 4 bytes, in some of the proposals. Could be 7, could be 11, check the
> address length field for details. Yee. Hah).

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