-----Original Message----- From: Jonah Yokubaitis [SMTP:barron@texas.net] Sent: Friday, August 08, 1997 2:08 PM To: Nathan Stratton Cc: Matthew White; nanog@merit.edu 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 http://www.genuity.net