The Items You Should Know in Fiber Network

When talking about fiber optic networking, the basic requirements include understanding single-mode vs multi-mode fiber and their uses, learning the connector types with familiarity (SC, ST, LC, MTRJ, etc...), understanding basic troubleshooting of fiber using OTDR's or even a simple fiber laser. Also, never look into that laser or the ends of fiber even if you don't visibly see anything. Point it at your hand or a surface to test if you're using a visible light. Understanding circuit types and speeds, as well as the medium some require (ds3 = coax, etc) and recognizing media converters and their role if required.

Here are a few things you should know about SFP, 10G SFP+, and XFP transceiver, which are the little plug-in tranceiver modules that go into switches that you plug fibers into. If you are buying any of those to terminate a new fiber run into some network equipment, make sure you buy them with the Digital Optical Monitoring (DOM) feature. Look at the data sheet of the SFP/SFP+/XFP you're looking to buy and just make sure it's on there. If not, find the equivalent model with DOM.

Cheap SFP transceivers and the like often do not have that feature and you have to pay a little more to get DOM, but it's hugely beneficial to have because you can get transmit and receive light level readings right from the CLI of your device (Cisco example, "show interface Gigabit Ethernet 0/48 transceiver") which is useful when troubleshooting errors on a fiber ethernet segment. If you have management access to both switches interconnected by a fiber run you suspect is bad or if you suspect bad SFPs, you can run that example command on both sides to see what the dB loss is or if the SFP is running way over temperature, etc.

At the very least, every (respectable) enterprise class switch should have a way to query those DOM stats. Cisco (not rebranded Linksys), Adtran, HP, Brocade, etc. should all have a command to do that, and especially any carrier grade gear like the Fujitsu Flashwave or the Adtran TA5000 switch modules.

The fiber optic transceivers on either end need to match types because there are several wavelengths that can be used depending on the length of the run. Though, generally speaking most campuses just pick one that works for the longest run and just uses those so they don't end up with twenty types of transceivers running around.

Unless you are going to be an actual fiber technician, you probably won't need to know much about actually terminating it. You'll be using pre-made patch cables most of the time, and connecting to fiber distribution points that were put in by third party contractors.