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Ethernet Rj45 Connector Pinout


Ethernet RJ45 Pinout

An Ethernet RJ45 pinout connector is a modular 8 position, 8 pin connector used for terminating Cat5e or Cat6 twisted pair cable. An ethernet rj45 pinout is a specific arrangement of cable or wires that dictate how the connector is terminated. 

There are multiple pinouts for ethernet RJ45 connectors including straight through (T568A or T568B), crossover, rolled, T1, and loopback. 


Straight through is the most common type of cable and is used for connecting your computer to your network. The other pinouts are for specialty cables that are used for unique network applications. 

Straight-Through ethernet rj45 Pinout Within the family of straight-through color codes, there are two standards recognized by ANSI, TIA and EIA. 


The first is the T568A wiring standard and the second is T568B. T568B has surpassed 568A and is seen as the default wiring scheme for twisted-pair structured cabling. If you are unsure of which to use, choose 568B.


RJ45 Connectors

RJ45 is a standard type of connector for networking cables that is widely used in Local Area and Wide Area Networking.


RJ45 stands for Registered Jack 45. RJ45 broadly refers to the RJ45 connector, RJ45 cable, an RJ45 port. An RJ45 Connector is an eight-wire connector used to connect computers in a Local Area Network (LAN) via Ethernets. 

RJ45 originally used in telephone cables was an 8P2C (8 position 2 conductor) modular connector whose pin 5 connects to the tip and pin 4 connects to the ring. 


Computer RJ45 is an 8P8C (8 position 8 conductor) connector with all conductors present. Today RJ45 is used almost exclusively to refer to Ethernet type computer connectors. 

In general, all 8P8C connectors are also referred to as ethernet RJ45 pinout cable connectors.


RJ45 cables fall into three main types namely a) straight-through, b) crossover, and c) rolled. The colored wires are in the same sequence at both ends of the straight-through cable. 

In crossover cable, the first (far left) and the second colored wires at one end of the cable are the third and fourth colored wires at the other end of the cable while the third and fourth colored wires at one end are the first and second in the other end. 


The colored wires at one end of the cable are in the reverse sequence of the colored wires at the other end of the cable in the rolled type. 

The most common ethernet RJ45 pinout connector cable uses four of the 8P8C wires for Ethernet communications. Pins 1 and 2 are the transmit pair while pins 3 and 6 are the receive pair.


The Ethernet port resembles a wider looking regular telephone jack. The cable and the RJ45 data port support communication at speeds up to 1 Gigabit per second (GBps) (one thousand million bits per second). 

In addition to Ethernet, RJ45 cable is used for WAN connections. Faster serial communications also employ modular 8P8C. 


Six of the eight connectors are used in certain Integrated Services Digital Network. Augmented RJ45 (referred to as ARJ45) to be used with a modified RJ45 port has been designed for high-speed communications (10GBps).


The benefits of using RJ45 / Ethernet connections are the high-speed data throughput reaching up to Gigabit/s levels over long distances. 

The other competing LAN standards like Token ring, Token Bus, etc., suffer degradation as when new nodes come into LAN. With a locking boot ethernet RJ45 pinout plug connector remains free of any inadvertent disconnection taking place.