Not every copper connection is the same. In this video, you’ll learn about RJ11, RJ45, F-connectors, and BNC copper connectors.
One common copper connector we use on our networks today is an RJ11. This stands for Registered Jack type 11. It is a six-position connector, but we only use two conductors inside of this connector. Sometimes, you’ll see this referred to as a 6P2C, for 6 position 2 conductor.
We commonly associate an RJ11 connector with an analog telephone, but you’ll also see RJ11 used for DSL connections since those use exactly the same wires as a telephone connection. Here’s a better view of the RJ11 connector. And you can see the six positions– 1, 2, 3, 4, 5, 6 are clearly marked– but you notice that there are the two conductors in the middle that are used for RJ11.
If you’re using an ethernet connection, then you’re using an RJ45 connector. And this stands for Registered Jack type 45. It is an eight position connector with eight conductors inside, so we’re using all of the conductors available on an RJ45 connection. This is slightly larger than an RJ11 connector, and it’s what you would use if you’re plugging in an ethernet connection.
Here’s a device that has both RJ11 and RJ45 connectors on it. You can see this is a DSL connection that uses the RJ11, and these LAN connections, or ethernet connections, are using the RJ45. You can see that they’re very similar in shape, although the RJ11 is slightly smaller than the larger and wider RJ45.
If you’re using a cable modem connection, then you’re probably bringing coax connections and plugging it into a cable modem. And the connector that you’re probably using is the F-connector. The F-connector is a standard connection type. It usually has threads inside that allow you to fasten it very securely to the connector. And if you are using a cable modem, this is probably the connection type that you’re using from the cable television infrastructure.
This is also referred to as a DOCSIS connector. That stands for Data Over Cable Service Interface Specification. The connection that brings the signal is the single copper connection on the inside of the cable. This is what you would plug-in and screw into a cable modem using that F-connector connected to the coaxial cable.
Another common connector used for coax is a BNC connector. This is a Bayonet connector, that’s what the b stands for, where you push it into the connector and twist it slightly to lock it in place. The NC in the BNC connector stands for Neill-Concelman. This stands for Paul Neill from Bell Labs and Carl Concelman from Amphenol. They both were involved in creating this standard for a BNC connection.
If you’re bringing in a WAN connection or any other type of coax, it’s very possible you might use a BNC connection to lock this in place. That is one of the benefits of using BNC, is that you’re able to push the connector in and twist it, and it’s not going to easily remove itself from that connection. You would need to untwist before removing that from the interface.
Here’s a close up view of the BNC interfaces on a device. You could see where you would plug-in the BNC connector. You twist that connector slightly and it’s locked in place onto that device.