Dear Mr. Antonov,

Thanks for taking time to enter this little spat about Internet collapses,
the growing importance of NANOG, and my cluelessness.

You wrote:

I was in a backbone engineer's skin for quite a few years, and "hops"
per se never were a problem. In fact, store-and-forward delays are
a mere fraction of wire propagation delays -- do a traceroute coast-to-coast,
look at delays and calculate how it relates to distance divided by speed of
light. Indeed, you're the first person concerned with the growth of diameter
(which is, BTW, logarithmic to size of the network).

Perhaps I am confusing terms here. How can it be a fact that
"store-and-forward delays are a mere fraction of wire propagation delays?"
I don't think so. Check me on this:

Packets travel over wires at large fractions of the speed of light, but
then sadly at each hop they must be received, checked, routed, and then
queued for forwarding. Do I have that right?

Forget checking, routing, and queueing (ha!), and you get, I think, that
store and forward delay is roughly proportional to the number of hops times
packet length divided by circuit speed (N*P/C).

For 10 hops of a thousand bit packet at Ethernet speed, that would be 1 ms,
or a couple hundred miles of prop delay. Check me on this, one of us might
be off by several orders of magnitude.

But at 30 hops of thousand byte packets at T1 speeds, that's, what? 4,000
miles of prop delay. A mere fraction?

OK, maybe soon the entire Internet backbone(s) will be ATM at 622Mbps,
which would certainly knock some of the wind out of N, P, and C. Soon?

But of course, getting back to 1996, N*P/C doesn't count checking, routing,
and queueing -- queueing gets to be a major multiple with loading. Oh, I
forgot retransmission delays too, at each hop. And I forgot the increasing
complications of route propagation as hops increase...

If I am, as you say, the first person to be concerned with the growth of
Internet diameter, which I doubt, then I deserve a medal. Or is my
arithmetic wrong? Ease my cluelessness.

/Bob Metcalfe, InfoWorld