(IPng 5002) Re: Last Call: IP Version 6 Addressing Architecture to Proposed Standard

On Dec 2,  4:48am, bmanning at isi.edu wrote:

> In short, I differ from Mike in that my values for "believed to be
viable"
> differ, apparently wildly, from his and brians.  I'm unconvinced that
> this will remain a true, long term technological argument. I'd like to
> see something besides, "too hard with 1990's technologies".  "Long time"
> ought to have a better spec than say, Internet Dog Years?

Bill,

What you say is true.  Technology is going to progress, and at some point
in the future we may convince ourselves that we can safely handle
1,000,000 TLAs instead of 10,000.  However:

1) We are not there yet.  Andrew Brodnik et al demonstrated that one can
   efficiently compress today's routing tables in the cache of a Pentium
   chip.  But their algorithm has yet to be implemented in commercial
   routers.

2) There is more to scaling than routers' caches.  Compressing the tables
   in cache memory mainly allows you to switch packets faster than if your
   tables were kept in a slow RAM.  It does not reduce route flaps, or
   the complexity of the topology.

3) In any case, we are taking decision today based on today's technology.
   As I pointed out, there is plenty of address space reserved for further
   use.  If the technology does evolve, then it will be time to open
   more space.

In short, limiting the size of TLA to 13 bits looks like a reasonable cut,
today.

-- 
Christian Huitema