The Difference Between TIA/EIA 568A and TIA/EIA 568B

Posted by Travis Gaerke on

TIA/EIA 568A and TIA/EIA 568B refer to the two major standards used in the networking and telecommunications industries. These standards determine the order of the wires placed in a RJ45 connector. With the only difference between the two standards is the placement of cable pairs on set pins, functionally both standards are the same. Knowing the different uses and pinout positions of each cable is essential to ensure a network’s proper functionality. We help you to better understand the difference between TIA/EIA 568A and TIA/EIA 568B.


The TIA/EIA 568A provides backward compatibility to a single pair and two pair USOC wiring schemes. While specific projects and temporary runs may specify the need for the TIA/EIA 568A standard—such as wiring done under federal contracts—the majority of applications in the United States use the TIA/EIA 568B standard. Unlike the TIA/EIA 568A standard, the TIA/EIA 568B standard provides backward compatibility to only a single pair USOC wiring scheme.

Pinout Positions

Pinout positions refer to the arrangement of pins on an integrated circuit. The difference between the two standards is the location of the orange and green pins.

The Pinout Positions of TIA/EIA 568A:

  • Pin 1: white and green stripe
  • Pin 2: green
  • Pin 3: white and orange stripe
  • Pin 4: blue
  • Pin 5: white and blue stripe
  • Pin 6: orange
  • Pin 7: white and brown stripe
  • Pin 8: brown

The Pinout Location of TIA/EIA 568B:

  • Pin 1: white and orange stripe
  • Pin 2: orange
  • Pin 3: white and green stripe
  • Pin 4: blue
  • Pin 5: white and blue stripe
  • Pin 6: green
  • Pin 7: white and brown stripe
  • Pin 8: brown

Different Cabling Types

  • Straight-through Cable: Straight-through cables refer to connectors at each end of a patch cable terminated with the same standard. Such cables are used to connect end-user devices to networking devices, such as hubs and switches, and send a signal directly through.
  • Crossover Cable: Crossover cables are terminated at both ends with different standards. In other words, one side is terminated with TIA/EIA 568A and the other is terminated with TIA/EIA 568B. To create a crossover cable, Pin 1 is crossed with Pin 3 and Pin 2 is crossed with Pin 6. Crossover cables connect two hubs through the data port or provide a direct connection between two workstations without using a switch or hub.
  • Rollover Cable: Rollover cables have opposite pinout positions on each end of the cable. Dissimilar to crossover cables and straight-through cables, rollover cables are designed to create an interface with the device rather than carry data.

Antaira Technologies is a leading industrial networking communication and technology manufacturer. For innovative and reliable industrial networking solutions, such as Ethernet switches, industrial wireless devices, and industrial PoE switches, shop our extensive collection of high-quality products today.

Share this post

← Older Post Newer Post →