I have two fiber cables in my patch panel — a single-mode simplex SC from my ISP, and a multi-mode duplex LC for 10 GbE network to my desktop computer.
Internet
When Altibox installs fiber, they usually install a wall-mounted coupler where they terminate the fiber coming from the outside junction box.
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From this box they use a short “pig-tail” SC-SC patch to the router/home central unit.
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Since I was planning to install a patch-panel, I didn’t want this wall-mounted coupler. So instead I asked if they could leave the fiber hanging, with a service loop. And they did 😃
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I initially connected the fiber from outside directly to my Altibox router.
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Through the patch-panel
Now — to terminate the fiber in the patch-panel I needed two things, a keystone SC-SC jack and a longer single-mode SC-SC patch fiber. Both simplex.
Fiber connector
Getting the right SC connector is important, the two most common types are SC/UPC and SC/APC.
- SC/UPC
- Ultra Physical Contact
- Extended polishing compared to PC connector
- Loss is -50dB or higher
- Blue connector color
- SC/APC
- Angled Physical Contact
- Polished at an 8° angle
- Loss is -60dB or higher
- Green connector color
These two connector types do not fit together, that may actually damage the fiber. Seeing as the patch fiber Altibox provided had blue connectors; it uses the SC/UPC connector.
Fiber cable
Furthermore; there are two kinds of fiber cables: OS1 and OS2.
- OS1
- Indoor application
- Tight buffer construction
- 1.0db/km attenuation
- 10 km max. distance
- OS2
- Outdoor application
- Loose tube construction
- 0.4db/km attenuation
- 200 km max. distance
I’ve read that OS1 and OS2 fiber can not be connected together, as this may lead to poor signal performance. I figured it was most likely that the they used OS2, since it had longer maximum distance and was rated for outdoor application.
I am quite confused by the OS1/OS2 fiber types, some patch cables I looked at didn’t specify the type.
While the one I bought said OS1/OS2 in the title, and OS2 in the specifications. I suspect this means that it’s an OS2 fiber, that is OS1 compatible.
I have no way of measuring if I have “poor signal performance”, the patch fiber I got does work — I know that much.
The most common standard for single mode fiber is 9/125:
- 9 µm diameter of the core
- 125 µm diameter of the outside of the cladding
Wiring it up
I ordered a 1 meter long fiber patch cable with the following specifications:
- SC to SC (UPC)
- Single mode 9/125
- OS2
- Simplex
- Outer diameter 2.0mm
- LSZH (low smoke zero halogen)
And connected it between the keystone SC-SC jack and the SFP module in the Altibox router.
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Success! 😄
I’m already planning to get a compatible SFP module for my Edgerouter 4, and skipping the Altibox router all together. But I’ll leave that for another day.
LAN
I also have a keystone LC-LC jack and a 7 meter multi-mode fiber going to my desktop computer, for 10 GbE networking, it has the following specifications:
- LC to LC
- Multi mode 50/125
- OM4
- Duplex
- Outer diameter 2.0mm
- LSZH (low smoke zero halogen)
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