How to switch optical patches?

Question

Computer networks

Good day, I beg your pardon for amateurishness, but I have never come across optics, but I need to. Tell me an article or in a nutshell tell me how to switch optical patches. Let's say we have N simplex patches, yellow and sfp modules for switches. I understand correctly that since simplex patches, and not duplex, then there are 2 simplex patches for each interface (rx and tx)? Then I connected the patches in sfp, in one of them I see, for example, light, then how to understand which of the patches to connect to which half of the interface on the cross? Crosswise or in parallel should the patches go?
Please do not kick, but I did not immediately find the answer to such amateurish questions, but I want to learn and do it right.

Answer 1

Maxim Kotov

Crosswise or in parallel should the patches go?

Cross over. On normal optics, there is even a tag with the numbers 1 and 2 or the letters A and B.
Although of course it all depends on what you will connect.
It happens that the transmission goes only in one direction and just simplex is enough.
But I'm considering the standard option for routers and switches.