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GLC-LH-SMD= vs =GLC-SX-SMD=

I'm curious ....

GLC-LH-SMD= vs =GLC-SX-SMD= are Cisco SFPs.  Long haul vs short haul.


Would having LH on one side and SX on the other work if the fiber between them was multimode (OM1, OM2, or OM3)?


LH are dual compatible (mode conditioners needed in some cases).
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Commented:
AFAIK, as long as wavelengths match on both sides, it should work.
Top Expert 2004
Commented:
That's exactly the problem- the wavelengths won't match. LH is 1550 nm and I believe SX is 1310 nm. Although the LH may work with multimode fiber, compatibility doesn't mean dual wavelength.

Author

Commented:
What do you mean?  Like having the same fiber type ran through?  

OM1 jumper - OM1 fiber run - OM1 jumper

Author

Commented:
They list SX as 850, and 1310 as LH/LX.
Top Expert 2004
Commented:
Ah, sorry about that. 1550 is used for single mode fiber. Either way though, the wavelength mismatch means they won't talk to each other. Imagine that you can only see red, and someone is showing you something that's yellow, and vice versa. The fiber type is irrelevant here.
nociSoftware Engineer
Distinguished Expert 2019

Commented:
Also using LH for short distances might provide too much light on the receiving end disabling it from seeing the signal. (Compare it to looking directly into the sun).