What is an RJ45 Port?. An RJ45 port is a model of connector that is commonly used for Ethernet networking. It is similar in appearance to a telephone jack even though it is slightly wider. Ethernet cables are sometimes referred to as RJ45 cables because they have an RJ45 connector on each end.
The ‘RJ’ in RJ45 is an acronym for ‘registered jack’ because it is a standardized networking interface. The ‘45’ on the other hand simply refers to the number of the interface standard. With each RJ45 connector comes eight pins, this means the RJ45 cable contains eight different wires. With a closer look at the end of an Ethernet cable, you’ll notice the eight wires, with each having a different color. While four of them are solid colors, the other four are striped.
RJ45 cables can be wired in two different ways. One version is known as T-568A while the other is T-568B.
An Ethernet cable is a cable used in connecting devices in a wired network to a server, modem, router, or each other. The end of each Ethernet cable has a connector which is called an RJ45 connector. RJ45 connectors are used almost exclusively with Ethernet cables and networking. Even though Ethernet cables have gone through various generations of speed improvements, the RJ45 connector that appears on the ends of the cables is still the same. So for whatever category you are using, be it category 3 through category 6 cables, the connectors are RJ45. Category 7 cables on the other hand can be terminated with RJ45 connectors, but they are specialized versions known as GigaGate45 (GG45). The GG45 connectors are backward compatible with RJ45 connectors. The features of Ethernet cables include small plastic plugs on each end which are inserted into the RJ45 jacks of Ethernet devices. Here the term ‘plug’ is for the cable or male end of the connection while the term jack is for the port or female end.
Even though the are eight pins of the plug connected to the eight wires of the UTP cable, understand that only four of those cables carry a charge. They happen to be the transmit circuit and the receive circuit. So each circuit is composed of two wires which is positive and negative. All computers listen on the receive for incoming data, they do not send data out on the same wires. Any data that leaves a computer, travel down the transmit wires.
Issues With RJ45s
The RJ45 is not without some issues. For instance, to form a tight connection between the plug and the network port, some RJ45 plugs use a small bendable piece of plastic known as a tab. The tab creates a tighter seal between a cable and a port upon insertion. This requires downward pressure on the tab to unplug it. Thus, the tab prevents a cable from accidentally coming loose. Now the issue is, that these tabs easily break when it is bent backward. This happens when the connector snags on another cable, clothing or other nearby objects.
Also, most RJ45 connector problems happen when the wires do not follow the prescribed standard. Thus people who prefer to work on their own cables and connectors have to pay close attention to the proper wiring sequence in order to avoid problems.