Re: Is anyone actually USING IP QoS?

[Vadim Antonov <avg () kotovnik com>]

Vijay Gill <wrath () cs umbc edu> wrote:

> > Scalability on the Internet pretty much means that algorithms should run
> > in O(log(N)**M) where N is the total number of end-points and M is
> > constant.  (Note that non-CIDR unicast routing doesn't fit this
> > criterion, but CIDR does).

> Reference to this?

I guess it's my private rule-of-thumb.  (Antique Kleinrock and Klein, maybe?)

Anyway, O(N) seems to be infeasible (as at least some network components will
have to scale at super-Moore's law exponential rates), and O(log(N)) - too strict
(all dynamic routing algorithms are super-linear, but still work).

The design based on O(P(log(N))) algorithms was demonstrated to work in practice
(DV  of SPF with route aggregation).  O(P(N)) (non-hierarchial routing) was
demonstrated to fail during the CIDR deployment saga.

> The pressure is being applied now.  Vendors however had a lock on this
> market, witness how long it took for cisco to give oc-12 atm interfaces.
> They didn't move till uunet put the GRF into the core.

The pressure is called competition :)

Unfortunately, large switching equipment vendors still didn't get a clue on
how to build real fast routers.  (Nortel may be an exception, with their
stake in Avici; however i have serious misgivings about ability of Avici
design to deliver on promises.  Hypertorus is not what one wants to use
for general permutations.  And i find their claim to be inventors of massively
parallel routing simply hilarious.  Obviously, their marketing department
employs Al Gore as a PR consultant.  Never mind that the only reference to the
name "Avici" i was able to find is the particularly hot kind of hell in
Buddhist mythology :)

--vadim