[NA] Extending fiber optic line?

[CJones]

OK.. I re-read my original post and it was too long and complicated.

Distilled version:
Does anyone have experience extending a fiber optic line (bonus points if it's AT&T fiber in a residential setting)? I'm trying to decide if I want to run ethernet (Cat5e/6) from where fiber comes into my house currently or if I could extend the fiber itself to where I eventually want to ONT (fiber modem) to sit, which is on the other side of the house from where the fiber is currently terminated.

Anybody done anything like this and know how difficult or finicky fiber is to add connectors, etc.?

 

[DaleB]

OK.. I re-read my original post and it was too long and complicated.

Distilled version:
Does anyone have experience extending a fiber optic line (bonus points if it's AT&T fiber in a residential setting)? I'm trying to decide if I want to run ethernet (Cat5e/6) from where fiber comes into my house currently or if I could extend the fiber itself to where I eventually want to ONT (fiber modem) to sit, which is on the other side of the house from where the fiber is currently terminated.

Anybody done anything like this and know how difficult or finicky fiber is to add connectors, etc.?

When a new fiber company installed service at one of our rentals, I told the guy I might relocate the ONT. He left me a 40’ fiber cable and a little plastic butt joint connector to plug the two together. Not being an expert on fiber stuff, I was kind of surprised you could do that… but it worked…

 

[Mikey52]

You can buy fiber extension cables off Amazon. You just need to know what type connector is used that plugs into the box.

 

[Spring Ford]

You need to match up the type of fiber. I have been out of this for a while but hopefully not much has changed. The fiber coming in to your house is likely single mode 8/125. Within premises multimode is often used 50/125 or 62.5/125 but I think this is unlikely for a telco. They seem to now have two kinds of single mode. OS1 and OS2. Most likely that you need OS2.

The numbers refer to the diameter of the glass bit and the core which carries the light (in microns I seem to recall). Format is core/total.

Most cables have the size printed on it every yard or two. There are a variety of different connectors used however when you have identified them you can get patch leads and barrel connectors that should allow you to extend the run. Don't use more than one extra joint.

I suspect that you will have a single fiber that works in both directions. I have never worked with these but I doubt there is a difference.

Here is a DIY guide to extending the cable. Happens to be a UK telco but principles will be the same.

How to Relocate the FTTP ONT | Expert Advice | Premitel

www.premitel.uk

Ask the ISP what kind of fiber they use and match it.

Don't get any dirt in the joints.

 

[Rgbeard]

Extending LC connectors is pretty simple, and in Mexico that’s the connector used by the phone company.

Don’t know what connector/fibre is in use by your telco.. Send a pic?

 

[CJones]

Well, I ended up grabbing a roll of Cat6 cable to run out and up to the attic - it's something I know about and have done before. The ONT (BGW320) has a 5Gbps port, and I only have 1Gbps service, so hopefully the single Cat6 line can handle everything. If not, I'll look at extending the fiber itself.

Thanks for the feedback.

 

[Eric S]

fyi cat6 under 300 ft can easily handle 10Gbps, so you should be good. Just get good quality terminators for the cat ends.

For extending fiber is pretty easy but running CAT cable is easier and less prone to issues.

 

[Albany Tom]

I didn't comment on the fiber part because that's out of my area of current experience. But Eric is right, on the copper side, you should be good to a total length of 100m, or just over 300ft. That's a timing limit, not signal strength. On the fiber side, the technology that the Internet providers use has a much longer distance limitation. AFAIK it's not Ethernet but something else. The only thing I'd add is that if the attic is hot, the modem might not like it. Data center stuff is rated to 80F recommended and 90F max these days, and consumer stuff may or may not be that good.

 

[pfarber]

if there is a fiber jack just buy the proper cable making sure it's at the right wavelength.

if you need to splice a connector then you need some kinda spendy hardware or call a guy.

 

[midwestpa24]

I have to say I learned something new from this thread, that fiber extensions exist and work. I help manage our small in-house network with fiber connections between buildings and never knew that, but I am far from being an IT expert. I still have to reread the directions when terminating Cat cables.

 

[Spring Ford]

fiber extensions exist and work.

Just be careful to match up the fiber type and respect distance limitations. Each connection does create a loss so if power is marginal you could bump into that.

Less expected might be distance limitations due to data rate. With multi-mode (usually in-premises) distance can be less at higher rates. This is mainly due to modal dispersion. The signal gets smeared out with distance because not all the light follows the same path (Multi-mode! Geddit?). One ray might go down the middle, one a little bit angled and bouncing off the sides and another more angled ...

Why would anyone use multi-mode? Well it costs less because it doesn't need lasers (LED lasers) to make it work. Simple and cheap LEDs are fine.

One possible gotcha is that some (especially) single mode installations require attenuators. Don't remove them by accident thinking they are simple barrel connectors.

Oh, finally, respect the minimum bend radius. Very important, as it is with Cat x too.

Oh, keep the ends capped at all times. Store in a reasonably clean environment in the original bag. I never touched the ends with anything. I never felt the need to try to clean one. The core (light carrying) diameter for single mode cable is about 1/3 of a thou. Quite small.

EDIT: A barrel connection is ONE connection, there is no intermediate medium. The fibers are just butted up to each other.

 

[Shepherd]

My entire house, including basement and garage is fitted out with fiber. Has been since 1986.
I was doing a lot of fiber experimentation/development for IBM Research back then. It was cheaper to design the cable system, patch panels and all the other stuff and install them in my house than fight for space (and permission) at the lab. I also had an IDNX 10 installed in the basement at that time.
IBM, of course decided it wasn't a "core business" and gave all the technology away.
My cable design was pretty cutting edge. Ethernet, Token-ring, 4 twisted phone pair and a pair of fiber optic cables (eventually 2 pair of fiber) all in one cable.
No one in the country was making anything like that at the time. I spent 6 weeks working at a mom and pop cable company in Florida, NY while we figured out how to manufacture it.
After IBM tossed the technology, the manufacturer sold millions of miles of the cable to the military and the government.
The owner went from a C-172 to a top of the line Gulfstream G-800.

 

[PaulS]

Fiber is finicky, especially single mode. The active core area is about 8 microns, which is smaller than most dirt. A contaminated connector surface can cause reflections that will degrade the signal. I’d just call at+t and pay the 150 dollars or so it would take to move the fiber where you want it. Once you screw up a connection it’s difficult to get it back unless you know what you are doing.