[off topic] Bomb Threat.

From: William Donzelli <william_at_ans.net>
Date: Wed Oct 21 15:10:19 1998

> The major infrastructures have tended to centralize around the commercial
> 'backbones' and carriers which make them succeptable to interruptions of
> service when a single connection fails! (Sure... your web servers are fed
> by dual 'T3s', but both from a single carrier thru a single POP?!?)

You are quite correct, but let me expand on it.

Most customers do get only one circuit to a backbone, and yes the things
go down. T1 or T3, or whatever you have, 99.9 percent of the time it goes
thru _one_ CSU and/or _one_ router. If the CSU dies or the router starts
flapping, the customer gets very upset. It is possible to have a customer
home multiple circuits into multiple routers (it is a bit difficult, and
not terribly efficient), but it just ain't done that way.

The problem lies within the confines of the POPs. On a greater scale, just
as the ARPA people envisioned, the backbones are very bulletproof. If a
circuit goes down between two POPs (largish ones, anyway), there will
always be another circuit to take the load. Sure, it may go thru an extra
transit router or two, and may saturate them, but the net will still be
up.

Thank goodness that most of the equipment deployed to make the Internet is
built like tanks.

William Donzelli
william_at_ans.net
Received on Wed Oct 21 1998 - 15:10:19 BST