[ale] An unnecessary outage

[Michael B. Trausch]

So I just had a nearly 24 hour outage on my cable services.  The root
cause?  Defective hardware: a condition existed on my home network that
triggered the mandatory SMC network appliance (cable modem/router
combination) to fail fantastically.  Something caused my Linksys
wireless access point to go wonky.  This caused the SMC cable
modem/router combination to just stop working.

This tells me three things.

#1, something is very wrong with the design of the SMC box.  It does not
isolate trouble to a single port as it should.  Anything that does not
comply with the Ethernet standard, or anything that is not functioning
properly according to the Ethernet standard, should _not_ cause the box
to lock up, drop its DOCSIS connections, and do nothing.

#2, the internal switch on the device must be bridging the four external
Ethernet ports together with an Ethernet port (virtual or otherwise)
internal to the device that represents the DOCSIS side of the modem.
This is probably why the failure of _ONE_ device on my network caused
the whole thing to go "tango uniform".  I'd be willing to bet that the
switch treats the USB port on the device as another Ethernet port, too,
but that's neither here nor there.

#3, the multiport bridge on the inside of the device, or the software
that drives it, or some combination of both, are very poorly designed
and/or buggy.  If I wanted troubles to propagate through my network I'd
use a bloody stupid hub!

I want this thing off my network.  I want it off my network five years ago.

Does someone here know a great deal about the cable network?  I want to
replace this.

But in order to do so I need to understand a little more about how it
works and how it gets my /28 to me.  Is it possible to do something like
use wireshark with a dongle of some sort that attaches to the coax, and
can look at the traffic on the coax?  Is it possible to buy a DOCSIS 3
cable modem and clone the MAC address of another modem on the DOCSIS
interface so that the cable company thinks that I'm still using the
modem they gave me and won't just refuse to talk to my new cable modem
(because AFAICT, "authentication" on the cable network consists of
having the right MAC address).

And why again is it that nobody seems to make DOCSIS 3 internal cable
modems?  Why do I have to have yet another AC→DC converter brick just to
power a stupid external one?  I really can't see an internal cable modem
requiring more power than, say, a video card or maybe a couple of
standard Ethernet cards.

	--- Mike