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Fiber cable question

I want to connect a switch in room A, to a switch in room C with single mode fiber LC.


Now there is a building in between, let's call it building B.


Normally if i were to connect a switch in room A to a switch in room B, i would patch from the patch panel to the switch directly.


Now I want to link it all the way through from room A to C. In room B, what type of cabling do I need? Can I just connect both patch panels there?


Hall of Fame Guru

Re: Fiber cable question

So you want to connect A to C but there is no direct link from A to C, however, there is a link from A to B and B to C.
NOTE: I'm going to presume that the links are all of the save wavelength, either SM or MM (and not both.
So you'll just need to find a fibre optic patch cord of the right length and terminating ends (LC, SC, ST or MTRJ) and patch the links in.

Re: Fiber cable question

Yes there is no direct connection between A and C, building B has patch panels to connect to either A or C.


Yes it's all SM.


Ok thanks. What is the shortest distance patch cable as the panels are really close together?


Is it 0.5 meters?

Re: Fiber cable question

Also what would be signal loss in such a scenario? Is it negligible?

How can you see this manifesting on a link? Increased error rate on a show interface command?

VIP Rising star

Re: Fiber cable question

SM optics have a range of 10 km and it sounds like you are in a campus environment not going anywhere near that. The loss should be negligible assuming fibers and connection points are clean and sound.

You should be able to any length you want for the fiber patch cable. There are pre-made lengths that afre probablt trhe better way to go, but you should have no problem just looking online.

The fact that you are patching through building B should have no affect on the error rate. If the fiber infrastucture is sound it should be clean and error free.


Re: Fiber cable question

Typically SM = yellow patch cable.  (MM = orange)  I know I can order 1 m, not sure about .5 m legnth.  You'll want to verify if all patching uses LC to LC, or what specifically you are using.  If SM fiber throughout you won't need a device to change over from SM to MM.


Re: Fiber cable question

OM3 and OM4 are aqua or blue. OM5 is green.

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