On Wed, Oct 3, 2012 at 4:15 PM, Owen DeLong <owen@delong.com> wrote:
On Oct 3, 2012, at 3:49 PM, Jimmy Hess <mysidia@gmail.com> wrote:
On 10/3/12, Jay Ashworth <jra@baylink.com> wrote:
So the address space for IPv8 will be... </troll>
In 100 years, when we start to run out of IPv6 addresses, possibly we will have learned our lesson and done two things:
(1) Stopped mixing the Host identification and the Network identification into the same bit field; instead every packet gets a source network address, destination network address, AND an additional tuple of Source host address, destination host address; residing in completely separate address spaces, with no "Netmasks", "Prefix lengths", or other comingling of network addresses and host address spaces.
Agreed, mostly.
Prefix lengths can still be useful for route summarization and it would be useful to have separate segments of the network address, such as Autonomous System Number, Intra-AS Organizational Identifier, and Intra-Organizational Network, for example. It might be useful to use prefix lengths in those cases to allow for variability in the boundary between these identifiers.
And (2) The new protocol will use variable-length address for the Host portion, such as used in the addresses of CLNP, with a convention of a specified length, instead of a hardwired specific limit that comes from using a permanently fixed-width field.
On this, I disagree… Once host identifiers are no longer dependent on or related to topology, there's no reason a reasonable fixed-length cannot suffice.
Need more bits? No protocol definition change required.
Nope, just new ASICS everywhere and no clear way to identify where they are or are not deployed and…
A regrettably serious response: There are some fundamental questions about areas of computer usage, engineering, and science that will affect what "the next protocol" should look like. Despite a couple of decades of frenetic work to mobility-ize our protocols, we mostly didn't with IPv6; that may be the norm rather than the design exception by $NEXTPROTOCOL. Quantum computers may, or may not, be relevant to anything (including possibly routing or switching) by $NEXTPROTOCOL days. Supermassive parallelism may be relevant to routing or switching. Moore's Law may peter out at some point with Silicon hitting atom-count limits, or could continue somewhat further with nanowires and graphene and the like, or something else completely could come about. Extremely low cost concerns may collapse the number of physical devices in a computer / computing device, as we have see many cycles of various system controllers or video controllers migrating into CPUs or back out again as performance or chip cost concerns / fab technology pushed the optimization point one way or the other. This could affect switch and router cost optimization as well. We can (probably safely) say that within the next decade there is no sign of a technical or business driver for $NEXTPROTOCOL bubbling over our feet; by the time that it becomes necessary or relevant, all the ASICS we have out there now will be obsolete. Whether they're just faster smaller ASICS or some form of interface we cannot currently accurately predict, I have no idea, but I would rather not limit our conceptualization of 20-100 year timeframe solutions to "Today, but faster". If we go back to 1992, it is almost completely an accident that winning technologies in many areas today are still recognizable to the computer people of that era. -- -george william herbert george.herbert@gmail.com