Optical Fiber Connectors – CompTIA Network+ N10-007 – 2.1


The connector types between fiber-connected devices can vary. In this video, you’ll learn about ST, SC, LC, and MT-RJ fiber connectors.

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There are many different kinds of fiber connectors. So in this video, I’ll take you through some of the more common types that you’d find in any data center. The ST connector is the straight tip connector. And you can see by the connector itself, that it has a bayonet connector. You would push it in and twist it to lock it in, and then you would need to untwist and then pull to be able to release it. It has a rounded connector at the end, and you can see there’s a relatively long ferrule that’s sticking out, which makes it very easy to spot an ST connector.

The connector is commonly referred to as a subscriber connector. A standard connector or visually you can see it as a square connector. The square connector on these ends is very different than the rounded connector that was on the ST connector.

They’ve also got these plastic keys on these sections of the square so that you’re plugging it in in exactly the right way to the networking equipment. You still have a round ferrule in the middle that contains your fiber optic. And these push into a connection, and then pull out, which is very different than the bayonet that we saw with the ST connector.

As we progress through these connector type, you’ll notice they’re getting smaller and smaller. That’s because the manufacturers would like to put as many interfaces as possible in their networking equipment, and a smaller fiber connector means that they can put more interfaces on a single card. One of these smaller types of interfaces is the LC connector that stands for Lucent connector. It can be referred to as the local connector, and some people refer to it as the little connector.

With the LC connector, both sides of the fiber, the transmit and the receive are molded into the same connector itself, and there’s a locking mechanism on the top very similar to an RJ45 connector you might find with a copper connection. Of course, these can also be used as individual fibers, and you’ll notice that the size is a bit smaller than the ST and the SC connectors that we looked at earlier.

And the last type of fiber connector will look at is the MTR connector. This stands for mechanical transfer register jack. Some may say it refers to media termination recommended jack. In either case, it’s the smallest connector that we’ve seen so far. This is perhaps the smallest form factor of connector that we’ll have in this video series, and you can see we’re able to fit the transmit and receive fibers into a form factor that is about the same size as an RJ45 copper connector.