350 feet of cable from demarc

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KuJaX

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Does anyone know if running around 350 feet of 18 AWG Coaxial Cable causes any degregation or latency issues with cable internet?

We have a location that is about 350 feet away within the same building of the demarcation point within the building of where the cable company has terminated the cable. We are looking to basically extend 350 feet or so to the absolute further part of the building to setup the modem/router/switch/firewall/etc.

Is there a better solution? We want to limit latency and wireless isn't an option.
 
I would recommend RG11 at least. You can always call the cable company and see what they say.
coax_table.gif
 
For that run RG11 would be advised.

Is fiber and media converters and option? Meaning, would it be possible to have the modem at the point of demarc along with a media converter?

Edit: We've got a couple of customers on this setup along with a few point-to-point fiber customers utilizing media converters
 
Ehren8879 said:
For that run RG11 would be advised.

Is fiber and media converters and option? Meaning, would it be possible to have the modem at the point of demarc along with a media converter?

Edit: We've got a couple of customers on this setup along with a few point-to-point fiber customers utilizing media converters
Click to expand...

Thats what I would do. Have your ISP WAN device at the drop location, then run fiber from that to your router/firewall/load balancer/whathaveyou.
 
Krazypoloc said:
Thats what I would do. Have your ISP WAN device at the drop location, then run fiber from that to your router/firewall/load balancer/whathaveyou.
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yep, i'll agree with that too and i'll bring up a few "why's" too.

The cable system changes, fiber doesn't. Over the years the signal requirements for modems have and will change. RG-11 will work great now but 7-10 years from now it might not provide the signal required at that distance. Fiber is a better option for long term. Sure, the laser tech has changed a lot over the years but generally it's still the same fiber.
 
Ehren8879 said:
For that run RG11 would be advised.

Is fiber and media converters and option? Meaning, would it be possible to have the modem at the point of demarc along with a media converter?

Edit: We've got a couple of customers on this setup along with a few point-to-point fiber customers utilizing media converters
Click to expand...

It is possible we can run fiber instead. We are trying to do this economically. What would we need to do the fiber route? I assume we would need some type of converter for when it gets into the switch that is 350 feet away.

Any links to product? I also don't know what fiber type or whatever would be compatible.
 
Or maybe run 150 feet and then have the cable modem there and then run from the cable modem 150 feet with cat5e or cat6 to a switch?

or would we be better off running coax all the way or fiber all the way (the full 350 feet)?
 
Run the fiber from the demark.

You'll have to get someone to do it, as you cannot buy a pre-terminated fiber patch cord that long. It's likely to be expensive. But no one ever regrets doing things the right way.
 
Another non-crazy option...

Another option would be to place the cable modem at the dmark and run two cat6A solid run from the modem to your switch. The cable and terminations need to be in perfect cat6A spec. But you should have zero problem running that line at 1Gbps. It's also possible that that line could run 10Gbe in the future and still be in spec.

Note this is not a Cat6 run. This needs to be a Cat6A run.

Fiber would be much prefered, but at 330' Cat6A is still within spec for 10Gbe.


For 10Gbe the 330' limitation assumes you are using solid perfect Cat6A bonds/terminal for the main run but also allows for 33' of Cat6A stranded patch cable combined at the ends.

So if you Run Solid Cat6A from the Dmark straight into a switch. You CAN stay in spec at 360'.

For running at 1Gb speeds Cat6A the spec is for the same distance....but in practice you can go a little farther.

http://en.wikipedia.org/wiki/Category_6_cable
 
KuJaX said:
It is possible we can run fiber instead. We are trying to do this economically. What would we need to do the fiber route? I assume we would need some type of converter for when it gets into the switch that is 350 feet away.

Any links to product? I also don't know what fiber type or whatever would be compatible.
Click to expand...

We have a mostly single mode fiber on our plant and use mainly more expensive Transition MC's, but these Trendnet multimode MC's don't get horrible reviews.

If you're OK with a 100 Mbit connection then these are only $50 each:
http://www.newegg.com/Product/Product.aspx?Item=33-156-006&ParentOnly=1

Gigabit $113 each
http://www.newegg.com/Product/Product.aspx?Item=N82E16833156017

You'll need a pair of whichever type you choose. If you aren't familiar with how these work a short Cat5 jumper will go from your cable modem to one of the media converters at your demarc location. Fiber will extend to the destination where it plugs into the other media converter. Then it's simply another Cat5 jumper out of it into your switch, router, firewall, whatever. Media converters require virtually no configuration, you just plug in the fiber and they do their job.

Finding a place to buy a ~350' mulimode jumper pre-terminated with SC connectors is the next part. I usually buy my fiber locally, but I'm sure you can call a supplier and they'll sell you what you need.

These media converters will introduce no noticeable latency and you won;t have to worry about signal loss introduced by the extended coaxial run. In the end running fiber will save you time, money and frustration.
 
dandragonrage said:
Nobody should be okay with a 100Mbps connection limit anywhere.
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If you only have 20mbit/2mbit cable connection, and the modem is going to be the only thing on the other end, there is no reason to not be OK with it. The gigabit options aren't that more expensive though.
 
wizdum said:
If you only have 20mbit/2mbit cable connection, and the modem is going to be the only thing on the other end, there is no reason to not be OK with it. The gigabit options aren't that more expensive though.
Click to expand...

Because I would expect anyone with such a slow connection to be upgrading within the next year or two. 20Mbps is good.. 5 years ago.
 
dandragonrage said:
Because I would expect anyone with such a slow connection to be upgrading within the next year or two. 20Mbps is good.. 5 years ago.
Click to expand...

20Mbps is still 5 times faster than the average available speed in the US. If this is for a datacenter or big corporation, the solution would be to not put the NOC 350 feet away from the demarcation point. In two years the price of those gigabit media converters will be lower, and replacing them takes 5 minutes, including the time it takes to open the boxes. I agree, if the added cost isn't a problem for this application, go with the gigabit converters.
 
wizdum said:
20Mbps is still 5 times faster than the average available speed in the US.
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That's because of outliers like the mid-west. In actual populated areas, 20Mbps isn't very good. We need to be aiming WAY, WAY above 20Mbps as it's totally inadequate in this day and age. Even 50Mbps is quite mediocre these days when we have online backups, video card and other driver packages in the hundreds of megabytes (regardless of my connection speed, it REALLY friggin annoys me to download a 200MB friggin video card driver, so a big FU to Nvidia there), VPN between work locations, etc. Many businesses can survive on 20Mbps or less, but almost any business that has several+ users on PCs, they would benefit from faster.
 
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Regardless of which interface speed the OP goes with, I still think fiber is the way to go just from the electrical separation alone. When lightning strikes come in on the coax (assuming questionable grounding) it's nice to know that it's going to blow up the cable company's modem and perhaps the ethernet port on one media converter rather than "reach out and touch" all the way into your network.
 
Ehren8879 said:
Regardless of which interface speed the OP goes with, I still think fiber is the way to go just from the electrical separation alone. When lightning strikes come in on the coax (assuming questionable grounding) it's nice to know that it's going to blow up the cable company's modem and perhaps the ethernet port on one media converter rather than "reach out and touch" all the way into your network.
Click to expand...

I agree. Most people do not consider the surge potential of their cable line. Comcast keeps telling me they won't support me as long as I have ANY surge protector on my cable line - RIDICULOUS! I use one anyway. Been meaning to get an APC ethernet surge protector as additional protection, though I haven't let myself spend any money on that yet.

It also can help in the case of potential ground loops.
 
Personally I would go with a fiber line and use 100Mbit adapters at the ends.

Upgrade to gigabit later.
 
Ehren8879 said:
Regardless of which interface speed the OP goes with, I still think fiber is the way to go just from the electrical separation alone. When lightning strikes come in on the coax (assuming questionable grounding) it's nice to know that it's going to blow up the cable company's modem and perhaps the ethernet port on one media converter rather than "reach out and touch" all the way into your network.
Click to expand...

Good Point!
 
Ehren8879 said:
We have a mostly single mode fiber on our plant and use mainly more expensive Transition MC's, but these Trendnet multimode MC's don't get horrible reviews.

If you're OK with a 100 Mbit connection then these are only $50 each:
http://www.newegg.com/Product/Product.aspx?Item=33-156-006&ParentOnly=1

Gigabit $113 each
http://www.newegg.com/Product/Product.aspx?Item=N82E16833156017

You'll need a pair of whichever type you choose. If you aren't familiar with how these work a short Cat5 jumper will go from your cable modem to one of the media converters at your demarc location. Fiber will extend to the destination where it plugs into the other media converter. Then it's simply another Cat5 jumper out of it into your switch, router, firewall, whatever. Media converters require virtually no configuration, you just plug in the fiber and they do their job.

Finding a place to buy a ~350' mulimode jumper pre-terminated with SC connectors is the next part. I usually buy my fiber locally, but I'm sure you can call a supplier and they'll sell you what you need.

These media converters will introduce no noticeable latency and you won;t have to worry about signal loss introduced by the extended coaxial run. In the end running fiber will save you time, money and frustration.
Click to expand...

I'm not familiar with these converters, thank you for the info.

The cable internet is only about 10mbps so why would we go the gigabit route if we don't even have gigabit abilities from the cable company? Would we see any benefit from using the $113 converters over the $50 with this knowledge?
 
Media Converter route: DO NOT touch the Trendnet Crap. I was burned and went with this one in the end:

http://www.amazon.com/StarTech-com-...0810&sr=8-1&keywords=startech+media+converter

It has been rock solid.

Coax route: STRONGLY depends on what the signal is at the demarc point. If it's +15 dBmV or higher, you're good with RJ11 at that distance, if not, I wouldn't even attempt it.

Edit: Gigabit media converter for possible future proofing, why not?
 
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KuJaX said:
I'm not familiar with these converters, thank you for the info.

The cable internet is only about 10mbps so why would we go the gigabit route if we don't even have gigabit abilities from the cable company? Would we see any benefit from using the $113 converters over the $50 with this knowledge?
Click to expand...

The benefit of the gigabit adapters would be seen a few years down the road.

Comcast for example uses "powerboost" which allows your modem to use more bandwidth than you are paying for. Their 100/10 internet connection will burst up to 150mbit or so. If you were only running 100mbit converters, you would loose out on that.

In your case the benefit would be not having to touch anything with that fiber connection for 10+ years. 3 years from now the business may need a faster connection and that connection will also be more affordable. Not having to mess with anything is a good thing.

Why buy 2 more adapters 3-5 years down the road?
 
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