BBN (GTE) Suffers another major power problem.

Rodney Joffe rjoffe at
Fri Aug 8 22:03:13 UTC 1997

> -----Original Message-----
> From:	Jonah Yokubaitis [SMTP:barron at]
> Sent:	Friday, August 08, 1997 2:08 PM
> To:	Nathan Stratton
> Cc:	Matthew White; nanog at
> Subject:	Re: BBN (GTE) Suffers another major power problem.
> Incorrect. Stop using AC equipment in your pops. Use DC equipment and
> get a _good_ DC Powerplant. Every carrier Class4/5 switchroom usually
> has 10-20,0000 AMP/hours of standby power.  1 DSC or Nortel switch
> sucks _quite_ a bit more power than even the largest of superpops.
> Every carrier has _at least_ 4hours of battery plant (most have 8-12).
> Relying on generators is a _bad_ idea.
> Its not hard to have 4-12hours of standby battery plant.
> Lucent/Lorain/Peco2 all make rather nice rectifiers, and
> C&D/Lucent/GDB all make some nice vented batteries.  By going DC you
> also don't get hit with the inefficiencies of AC --> DC --> AC --> DC.
> You can bet that MCI/Sprint don't have a piece of AC equipment in
> their facilities and most likely are laughing their asses off right
> now.
Not quite as simple Jonah.... CO equipment is designed for 48v for many
reasons. It's also designed to deal with concrete floors, inefficient
HVAC, dust, etc.

Unfortunately, a modern megapop consists of a lot of interesting
equipment that doesn't come in 48v DC versions. Alpha 8400s, Large SGIs,
and server like things (yeah, I know, there are companies who make
retrofit kits for some of them, but they're not standard).

The real issue is planning... MAE E and MAE W *weren't* designed for the
things that MFS is stuffing in them. Most of the other pops have the
same problem. It *is* possible to design a facility that is run off an
inverter permanently, which is connected to a UPS, which is connected to
utility power, and to a diesel generator, which *is* able to cope with
extended failures of _utility power_ without affecting the equipment
(routers, switches, modems, and servers) at all. And I think the modern
facilities will be built that way. 4-12 hours of batteries is serious
when you're talking about a large hosting facility. Sprint/MCI may be
laughing, but they're haveing to scramble to build POPs capable of
supporting server farms because they can't do that now.

And another thing, batteries or not, *no-one* can easily survive a
catastrophic event like a fire, an explosion, or even the wires that got
eaten in BBNs Stanford center last year. (Didn't AT&T hose most of
Chicago's loop area a few years ago, for more than a *week*?) I bet they
had DC in their vault. Didn't help them much...

Rodney Joffe
Genuity Inc., a Bechtel company

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