RJ-45

RJ stands for Registered Jacks and RJ is standard connector used for telephone applications and as network cables. Sometimes it is also used as serial connections.

RJ-45 is a registered jack which specifies the physical as well as the wiring pattern. There are many other jacks other than RJ-45 and some of them are:

•    RJ-14 used for a 2-line telephone jack.
•    RJ-25 used for a 3-line jack.
•    RJ-61 used for a 4-line telephone jack.

The RJ-45 uses an 8P2C (8 position, 2 conductor) modular connector in which the some of the wires monitor the tip and ring of the telephone line and some of them are connected to programming resistors. The RJ-45 is an old technology and was mostly used in the outdated cable modems. This connector is composed of eight pins. Most of the people don’t even know that the shape of a hole in many of the walls of their homes are the RJ-45, but they also call a similar wire being used for computer applications as the RJ-45 which is not that right.

Actually this should be made clear that these both are two different things and the genuine RJ-45 telephone connector is not even compatible to be connected in a computer. The RJ-45 telephone connector has 2 positions in the middle which have conductors in them, whereas its pins 7 and 8 are connected to the programming resistor. Moreover the computer RJ-45 is the 8P8C in which all the 8 positions have conductors.

So the real telephone RJ-45 can never be used that effectively in a computer, but the computer’s RJ-45 is more popular because it is used in both telephone and computer purposes. All the 8P8C cables are used everywhere and are used in all the electronic equipments now a days.

source: freetechexams