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Re: Comcast outages continue even in areas with PG&E power restored


From: Lyle <lyle () lcrcomputer net>
Date: Mon, 14 Oct 2019 19:02:27 -0500

All true telco equipment is powered by batteries. Commerical power or generators just recharge the batteries. No switch over when commerical power is lost. Except when the generators(where equiped) switch over to recharge the batteries.


Comcast and telcos do not put batteries in all remote powered terminals. I have an Enterprise grade Ethernet over coax connection. The headend it's distributed from doesn't have batteries. If it loses power, doesn't matter if I have power or a generator or ups to take over. This Internet connection goes down.


For telcos(when I worked there), they usually had batteries that would last 4 to 8 hrs at remote terminals with powered equipment. And a connection for a splice crew to come out and connect their generator to it for power in case of an extended outage. Back then that was also how most cell phone towers were outfited.


I also have some knowledge of the commerical power grid in my local area. It's not unheard of for the Comcast headend to lose power but my office doesn't.

Lyle Giese
LCR Computer Services, Inc.

On 10/14/19 17:38, Michael Thomas wrote:

On 10/14/19 3:06 PM, Sean Donelan wrote:

That is not why people are surprised. When the house doesn't have power, and doesn't have home generator or UPS, (most) people are less surprised their DSL or Cable modem and VOIP doesn't work anymore.

The reasons I saw people angry on twitter was no Comcast service even when they had power at the house (utility, generator, UPS). Their Comcast service died quickly, even when the home had power but the Comcast outside plant didn't seem to have any backup power.

DSL modems also need power at the home, but the telco providers seem to have more backup power in the outside plant or central offices. That meant DSL worked as long as the house had power (or a home generator or UPS).

So it turns out that our local telco/isp does keep dsl running via the same mechanism as they keep pots power backed up (i'm guessing it's a diesel generator at the co, but am not sure). It seems that a lot of the pedestals terminating the local loop these days do the conversion to IP right there with sip/h.248/mgcp/rtp. I'm not sure how they get power to the pedestal, but these were all a home run to the co at one time so it probably wasn't hard to power them from the co. For all i know, that's how they're all powered all the time, with a transfer switch at the co, rather than tapping the local grid next to the pedestal.

Of course this is a lot of conjecture on my part... be glad to be clued in by folks in know.

Mike



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