Thus spake "Noel Chiappa" <jnc@xxxxxxxxxxxxxxxxxxx>
> From: "Michel Py" <michel@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
>> We aren't *ever* going to give everyone PI space (at least, PI space
>> in whatever namespace the routers use to forward packets) ...
>> Routing (i.e. path-finding) algorithms simply cannot cope with
>> tracking 10^9 individual destinations (see prior message).
> I think you're dead wrong on this. This reasoning was valid with
> 10^8 Hz processors and 10^8 bytes of memory it's no longer true
> with 10^11 or 10^12 Hz processors and memory (we're almost at
> 10^10 cheap ones).
The last time I heard, the speed of light was still a constant. And the
current routing architecture is based on distributed computation.
I.e. router A does some computing, passes partial results to router B,
which does some more computing, and in turn passes the partial
results to router C. After some amount of this back and forth across
the network, the route is eventually computed and installed.
Needless to say, the real-time taken for this process to complete - i.e.
for routes to a particular destination to stabilize, after a topology
change which affects some subset of them - is dominated by the
speed-of-light transmission delays across the Internet fabric. You can
make the speed of your processors infinite and it won't make much
of a difference.
Nothing has changed here. The propogation of an individual route is limited
by the speed of light (in fiber or copper), yes, but faster CPUs and bigger
memories mean that more of those routes can be propogating at the same time
with the same or less effect than a few years ago.
The IPv4 core is running around 180k routes today, and even the chicken
littles aren't complaining the sky is falling. Compare to how many routes
were around pre-CIDR and the resulting chaos. Routers have gotten much,
much better since then, and in most cases they're using technology 5+ years
behind the PC market (200MHz CPUs, SDRAM, etc.). We'd have to seriously
screw up to run afoul of today's limits, and the vendors can easily raise
those limits if customers demand it (though they'd much prefer charging
$1000 for $1 worth of RAM that's too old to work in a modern PC).
S
Stephen Sprunk "Stupid people surround themselves with smart
CCIE #3723 people. Smart people surround themselves with
K5SSS smart people who disagree with them." --Aaron Sorkin
_______________________________________________
Ietf@xxxxxxxx
https://www1.ietf.org/mailman/listinfo/ietf