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Newbie question - residential access extension...

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Newbie question - residential access extension...

Wanting to extend network (Ethernet for Internet access) between two buildings.

Have a 1000 foot conduit between with coax in it. Too far for MoCA. One option is to pull fiber, but wondering if doing a DOCSIS network could make sense? Would someone help me think through the viability?

On one end I'd need a CMTS -- I see I can get a Motorola BSR1000 on eBay for $500 or so. On the other I'd need some sort of compatible Cable Modem. What I don't understand is whether or not the 1000' distance will cause me issues. Do I need amplifiers or anything? I know MoCA has about a 300' distance limitation, so I figure DOCSIS needs something to extend range... Are there a bunch more details I'm missing (I'm not sure if the CMTS does everything necessary to push configurations to my cable modem or if I need separate services for that).

Thanks in advance. Interested to learn even if this option makes zero sense.

The 1000 foot distance would

The 1000 foot distance would be no trouble at all for DOCSIS.
That's a DOCSIS 2.0 CMTS though, so you'd be limited to ~38 Mbps one way and ~10 Mbps the other.
Also, to get it working you'll need at minimum a DHCP server and a TFTP server, with a config file for the modem. (both software can run on any random PC you've got lying about though.)

Thanks for the reply.

Thanks for the reply.

Any recommendations on a DOCSIS 3.0 CMTS I could reasonably expect to find on eBay for less than a grand? A quick search netted devices in the $5K+ range only.

At what distance do you think amplifiers are needed?

1000 feet ?

Is it pure coaxial or fiber + coaxial mixing distance?

Could you not use HPNA;

Could you not use HPNA; something like:

Well, heck -- that looks like

Well, heck -- that looks like a great option. I was aware of MoCA but thought Home PNA was over power lines only. Looks like MoCA offers superior performance but far worse range, so HPNA seems perfect for this P2P application.

Thank you for suggesting this... even if it doesn't work well, will be out less than a hundred bucks.

Home Networking Terminology and Standards

Coax Home Networking
I have found the home networking domain and its associated terminology confusing: EoC, MOCA, HomePlug, HPNA, HomePNA, HCNA,, HomeGrid...
that said, I understand it might be something like this:

Home Phoneline Networking Alliance > HPNA > HomePNA > HCNA (alternate name? for HomePNA 3.1 which adds support for coax)
HomePlug Powerline Alliance > HomePlug AV(2) (adds support for coax)

I think maybe HomeGrid and has now absorbed HomePlug and HomePNA.

A few useful details:

MOCA 500-1650MHZ 300 feet
HPNA 12-44MHz 4000+? feet
HomePLug 2-30(86) MHz ? 2-100 MHz ?


1000' distance

Is it pure coaxial or fiber + coaxial mixing distance?

It's copper only.

It's copper only.

I think you need a amplifier.

if it is a 1000 feet of coaxial, the attenuation is large,I think you need a amplifier.

The only reason why a docsis

The only reason why a docsis network would make sense is if the building you are trying to reach was a MDU (multiple dwelling unit) such as an apartment complex.

The reason is that you could easily control how much bandwidth each customer got, and avoid having to run cat5/6 to each residence.

1000' is within the realm of docsis distances, however, it totally depends on the size of the Coax you have in your conduit, and the frequecies you are interested in. Higher frequencies attenuate faster than lower frequencies. This is why in a traditional trunk and feeder plant, you have amplifiers spaced every so often, to not only bump up the signal, but to also adjust the tilt, i.e. the power level of the lower frequencies and the power level of the higher frequencies. There are a lot of other reasons than that, but with 1000' spacing only lower frequencies would reach. this is all assuming you have consumer grade coax, like the coax you traditionally use in a dwelling. If you had larger coax i.e. what they use in outside plant you could potentially get 1000' with just coax.

This is why they created the HFC (Hybrid Fiber Coaxial) networks we see today. For long distance runs they use Fiber, then at the other end they place a fiber node, which takes fiber in outputs RF. This RF signal is regenerated every few hundred feet or so with AMPs and delivered to customers.

If you need a docsis network I would highly reccomend the HFC model, eliminates most if not all of the downsides of copper RF. Mini nodes run on $150 range, and used transmitters and receivers are not too expensive either, though the combination could break your $1000 budget.

If you are serving only a handful of customers, a L2 fiber network is best bang for your buck i.e. with cisco switches on either end with LH optics. A good place to get used switches and optics is cablesandkits. A wireless shot is also doable if your bandwidth needs are low < 600 megs. For wireless ubiquiti has multiple products that work well in that range, see their airmax and airfiber lines.

What kind of bandwith do you

What kind of bandwith do you require?
Moca uses 1000Mhz+
Docsis uses (depending on the design) 200-800Mhz for downstream

Ethernet over Coax (EOC) has limited bandwith (some in the range of 200Mbit or so) but uses lower frequenies (usually <65Mhz). This has much less attenuation. General specs are referring to 700m as possible (In some datasheets I see 70dB range).

Maybe other solutions are also possible. You can get 100Mbit (or even 1Gbit) wireless laser links, or use WiFi (5Ghz or eg 24Ghz like Ubiquiti Airfiber). can easlly archieve 300Mbit or higher, as long as you have a line of sight.

You can also mix both, to archieve redundancy.