Re: ATM comes and goes

[Albert Manfredi <[e-mail]>]

[e-mail] wrote:
> You have that right.  As you know I am not sure it (ATM) is such a
> super idea in the WAN area either.  Since you seem to be engaged
> in this "debate", it might be interesting to discuss some
> alternatives with you.  When I was in Germany last year I
> worked on something that I called "Just In Time" switching.
> This concept is designed to provide fast (both low latency
> and high bandwidth) "virtual circuit" (though more 'real' than
> ATM's SVCs) connectivity making use of Wavelength Division
> Multiplexing with very low overhead - but still electronic,
> in fact bit serial per wavelength - switching.

The only thing that matters is how long it takes to set up a circuit with
this scheme as compared with ATM (in the WAN). What you describe is
analogous to frequency division multiplexing using RF. You have to
assign a frequency and bandwidth to the new request for service. Is it
easier to do this way than it is to set up an SVC with QoS with ATM?
That's what matters.

> I find that
> with a 28.8 modem my performance at home is nearly always as
> good as my performance at LLNL where we have a very high speed
> feed (T3+) to the "Internet."  While I am definitely a bandwidth
> junky, I have very little motivation to upgrade even to ISDN
> because I don't expect much of a performance improvement (yet).

A strange comment for someone who doesn't like B-ISDN (ATM).

"Upgrading" from a 28.8 modem to ISDN, unless you're going to use
multiple B channels together, is no big deal. It's about as dramatic as
upgrading from the 1.44 Mbyte diskettes to those 2.88 MByte floppies that
flopped. A 2:1 improvement is hardly worth the bother, if any real bother
is involved.

The only upgrade worthy of consideration would be B-ISDN, or anything
beyond ISDN. And the type of use you're talking about, i.e. a direct
replacement for a telephone line, would not be difficult for ATM.

Bert
[e-mail]