[SATLUG] Grande Comunications down last night

herb cee hc at lookcee.com
Sun Jan 11 18:14:55 CST 2009

FIRESTORM_v1 wrote:
> As someone that works in the cable industry, there is something I need
> to say on this issue.  I don't think that a lot of it applies, but a
> well-informed customer is a smart customer. Since I'm in Houston and
> went through Ike, I got to experience firsthand how uninformed people
> are about how the cable network actually works.
> First off, a little bit of terminology:
> Headend - the point where the cabl signals are originated. These are
> the large windowless buildings where the server farms, muxes,
> switches, signal aggregators, etc are that generate the cable TV, and
> high speed data signal. The headend has a backup generator that runs
> on diesel and is staffed with technicans in the event of a major
> disaster. A  typical headend has several large satellite dishes and
> antennas.
> Hubsite - This is a small windowless building, usually about 400sqft
> that has additional equipment for the more localized area such as VOD
> server farms and vaults, fiber receivers and transmitters, and the
> digital upstream and downstream for the settop boxes and high speed
> data services (both digital phone and high speed data)
> Node - This is the "neighborhood endpoint" where the RF signals are
> translated from the fiber into coaxial RF and is sent down the coax to
> the taps and eventually ends up at the customer site. The node gets
> its power from the coaxial cable from power inserters.
> Power Inserter - does what the name implies.  These devices are small
> cabinets that contain a voltage regulator and several batteries (24V
> marine deep cycle batteries if memory serves). The cabinets are
> usually about 3ft tall, grey and have a utility meter on them or close
> by. They are connected to utility power and are where the coax plant
> get their power for operating the nodes, line extender amplifiers and
> system amplifiers. There are many power inserters for a single cable
> plant, depending on how large the area is that is being served by the
> node.  Think of the coax plant as one big buss system not too unlike
> 10base2, where the power inserter is not necessarily next to the node,
> but it is somewhere close.
> Tap - This is the point where the customer's drops are connected to
> the cable RF plant.  These devices are usually in the backyard or up
> on a pole.  The underground covers are about a foot in diameter
> cylinder that is in the backyard every two to three houses depending
> on spacing.
> The layout is something like this:
> (Headend)--------SONET fiber----------(Hubsite)-------Point-to-point
> fiber--------(Node)==CoAx==(Power Inserter)====(Taps)
> |<-------------------------------Fiber
> Plant---------------------------------------------------------->|<-------------------Coax
> Plant-------------------->|
> During Ike, where commercial power service was out, we had deployed
> many generators to the power inserters to keep the cable plant
> operational and many of our techs pulled insane hours repairing and
> verifying that the fiber plant and the coax plant were operational.
> We had full plant (all nodes responding) within I believe four days of
> Ike's passing, and the Ike-related outages were resolved a week later.
> Our biggest hurdles were people stealing our generators, destroying
> the power inserters for the batteries, flooding and the lack of
> utility power. We had almost 1,200 techs in the field for the two
> weeks after Ike to get as many trouble tickets resolved.
> It's not that the ISP's treat the Internet any less than the other
> services that offer (at least not in Houston), far from it.  Our
> network is constantly being monitored for trending and a tech is
> dispatched if 10% of a node's cablemodems drop offline. If we get more
> than 15 people calling in to open video issues on a single node, then
> we roll a tech to address the customer's issues and also roll a plant
> tech to address the plant to see if there's something else that could
> have caused it.
> Now, I can't speak for any company, (not even the one I work for) but
> I can tell you that we do everything in our power to ensure that our
> services are available as much as possible but sometimes the reason
> for the outage is something we have no control over.
> just my .02c, well actually a bit more, lol, guess I got wordy.
I for one appreciated your and Henry's 2c and the time you took to 
outline the Cable biz operation, and situation.
herb c

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