Most of our network connections are going to use copper as a physical media. In this video, you’ll learn about some of the most popular ways to connect our copper networks together.
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In networking we connect a lot of different devices together. And because of that, we have a lot of different connector types so that all of these different devices can communicate with each other. In this video, we’ll look at some of the most popular copper connectors that we use in networking. If you’ve ever connected a telephone or plugged in a modem connection, you’ve probably connected in RJ11 connector. It is the small connector that you’ll see with the tab on the top that locks it into place when you plug it into the port.
And it has these connectors on the outside of the cable if you look. Generally we refer to this as a 6P2C connector. That means it has six positions and two conductors, but generally you’ll find these cables are wired with technically an RJ14, which means there are six positions and four conductors. It’s ready to be used for dual line use, and if you look closely, you can even see the black, the red, the green, and the yellow wire inside of that RJ11 being connected to the end of that RJ11 connector.
For most of our ethernet connections we’re using an RJ45 connector. This is a little bit wider than the RJ11, and this is an eight position eight conductor cable connector. You’ll see all eight of those on the end of the connector if you look at it. All eight copper connections are there and being used for these ethernet connections.
This is also a very similar shape for something called an RJ48C. That C connector is one that is used for T1 or WAN type lines. The cabling inside of these may be different on both ends, so it’s very common to look at them to see exactly how they’re wired. But you’ll become very accustomed to seeing this RJ45 connector on the outside of your ethernet connections.
A standard that’s been around since the 1960s is the RS232. That’s technically a Recommended Standard 232, but you’ll never hear it referred to that way. We always refer to it as an RS232. This is commonly used for serial type connections. We’re connecting a modem to our computer. We’re connecting to a switch or a firewall or router so that we can configure it through a serial connection. We used to use these four mice and printers, but now we’ve upgraded all of those to the USB type connectors.
You’ll notice that there are different sizes of an RS232. There’s these different sizes you see in this table, a D, A, B, C, D, and E. Generally we refer to everything is db because the DB25 was so prevalent when the standard came out that when this nine-pin connector came out we started calling it a DB9. But as you can see the technical term is a DE9. You’ll rarely see it called a DE9. You’ll always hear somebody refer to it as a DB9 connector. And you can see those connectors are on the back of your motherboard or perhaps the cables that you have and that’s where you’ll be plugging in a serial connection to connect to a modem, to configure a router, or to perform some other type of administrative function.
Occasionally you’ll be running a cable and you’ll find that it’s just a little bit too short. It would be nice to be able to combine cables together so you can extend the length of them, and you can do exactly that with a coupler. This lets you do exactly this for an ethernet, maybe an F-connector or for coax. Maybe you’ve got a BNC connection that you need to extend. These couplers are perfect for doing that.
This is usually something you would do in very specific cases, however. Every time you’re putting a coupler in line you’re losing signal across that link. And if you’re going a very long distance, you may find that the signal loss is too much. You can’t make it from end to end with a coupler in the middle. That’s why we often decide to do end and complete runs from one end to the other without any disconnections in between. That way we can be a assured we’re getting the best possible signal all the way through the line. But if you need something for temporary use, maybe there’s a specific case where you don’t have a choice, you need to extend this cable, a coupler may be the perfect thing to use.
A BNC connector is a connector that was designed by Paul Neill at Bell Labs and Carl Concelman at Amphenol. This is a connector that is a bayonet connector. That means when you connect it you can turn it and it’s locked in place. It’s not going to go anywhere. It won’t accidentally pull out of that connector. If you look closely, there’s this tiny little latch at the end of the connector. So you turn it and it snaps nicely into the connection. You’ll see these in things like 10BASE2, when you’re using RG-58 thin net, like this one right here where you’re plugging in with a BNC connection on both sides.
These days you commonly see the BNC used on WAN links, like T3 connections that are commonly provided to you over coax and then commonly have that BNC connector at the end. These BNC c connectors are commonly used with coax, and if you’ve got a lot of coax cable it’s going to be taking up a lot of room. And some of these BNC panels put things very close to each other.
It can be difficult to get your fingers in there to connect or disconnect one single BNC connector inside of that. You’ll sometimes find special tools that are used to extend your reach and wrap around the BNC cables just because of that. But overall it’s a connector that stays in place once you put it there, and if you need to be sure that it’s not going to accidentally pull out of that connector, you may want to use something like a BNC connection.
We commonly see F-connectors on the end of RG-6 cable, when it’s used for television connections for instance, and since that’s used by our cable company, we commonly see it for cable modems as well. It’s a threaded connector– you can see the threads if you look closely– and when you’re putting this on to the connection you would screw it in and even sometimes tighten it down, and that makes it very difficult for this to accidentally disconnect from our F-connection.
If you’re ever in a data center and you look at the back wall you may see an entire wall filled with wires, and this may be something left over from the old analog days of audio where we plugged in all of our phones and punched them down to the 66 blocks. Some very old digital links might also be connected to some of these 66 blocks. You can see that the left side is patched to the right, so generally you have the connectors on the left behind this block are connected to these on the right. So you can punch down a lot of connections and then extend that over to the other side of the punch-down block.
You generally need both the wire and a punch-down tool, so it’s going to take some extra effort. You can see that this is not something very modular to work with. You really have to have the right tools to be able to get those wires into those very small connections so that they can make that link through the insulation to the copper underneath. We generally see people migrating to 110 blocks these days, so if you go into an environment that has a little bit older equipment you may see both 66 blocks and 110 blocks on the wall at the same time.
A 110 block works in a similar way to the 66 block. We’re punching down wires into this device and then connecting those wires to others. This is our block that allows these cables to meet in the middle. This has effectively replace the 66 blocks, so if you’re running a Category 5 or Category 6 network connection, you’re probably running it through a 110 block. This works by first punching down all the wires on the bottom– you can see them in this picture– and then you put a connecting block on the top and now you have additional wires you could punch down at the top to complete that connection.
Let’s get a picture where we can really look at this. You can see those cables in the back a little bit that are wired down, and then there’s an additional block on the top. And then even it looks here like someone has punch down a circuit that extends across multiple wires all at the same time, something you’d commonly see on a voice-type network, for instance. These are great blocks to work with. They certainly work for your ethernet connections. You just have to make sure that you’re well organized with where the wires are going and that you have the right tools to use for punching these down.
Category: CompTIA Network+ N10-006