Verizon outage in Southern California?

Speaking on Deep Background, the Press Secretary whispered:

I'm not completely familiar with the telco jargon.
Does Tandem mean the same as a local central office, where
POTS lines terminate at the switch? Long Beach has a population
of 470,000. The C/Os I know of are:

A "Central Office" switch talks to subscribers aka end-users.
On its backside, it talks to other CO's and tandems. Time
was, that was also VF copper pairs, but it's long since all
DS1 and up.....

A tandem is a switch that talks not to subs, but only to CO's. In
days of old, when a {dialup} call went to the other side of town,
chances are it went you-yourCO-downtown tandem-joesCO-joe. {copper
all the way...}.

A tandem was always housed in large CO building, but might have
been ATT's vice the operationg company, etc...

But ESS's and ""classless switching"" and massive expansion of the
plant really muddled the picture. An ESS could be both a CO switch
[for multiple prefixes and even multiple NPA's..] AND act like a
tandem.. And oh, the actual "line cards" can be remoted 100 miles
away in a horz. phonebooth box alongside the road in Smallville....
with DS1's/OC coming back.

My guess is a DACS, a cross-connect point that is an software-driven
patch panel, lost its marbles. [engineering term of art.....]
A DACS could have dozen->MANY dozen DS1/DS3/OC-n going hither
and yon. Some will be leased circuits. Others will be the CO trunks
going from one switch to another. It may/may not have muxes internal,
so that what arrives on a DS1 leaves in a OC96..

I note it went down at 2:20 AM. That SCREAMS software
upgrade/cutover. What's to bet GEE, no...VZEEE, was doing just
that and there was a major ohshit.

Sean noted a long while back that somehow, DACS crashes always
seem to take hours to recover. Maybe the backups are on Kansas
City standard tapes, I donno.. but this sounds like that..

Hash: SHA1

I wonder what ever happened to redundancy? I guess 5 9s (dunno what the
going number is) got blown out of the water for them.


David Lesher wrote:

5 9s can be measured all sorts of ways...

Network wide, it probably isn't even a blip. Even in terms of all of California service its probably not much more than a blip.

Vicky Rode wrote: