Ethernet Patch Cables VS. Cross-Over Cables

Posted on by FS.COM

router-cableEthernet network cables such as Cat5e cables, Cat6 cables, and Cat6a cables are some of the most popular forms of cables that are used to connect devices on local area networks such as PCs (personal computers), routers, and switches. Ethernet network cables can be divided into two different types: Ethernet patch cables (also called straight-through cables) and cross-over cables. Since they are fundamentally different, each of them has a different function in a Local Area Network (LAN). Now, let’s learn their difference in the following sections.

T-568A & T-568B Pinout Overview

Before introducing the difference between Ethernet patch cables and cross-over cables, it’s very necessary to learn about the T-568A and T-568B standards. As we know, an Ethernet network cable is a cable with 4 pairs of wires connected by RJ-45 connectors (a modular 8 position, 8 pin connector) on each end. Pinout is the specific arrangement, or order of wires that dictate how the connector is terminated. It is defined by the T-568A and T-568B wiring schemes, based on TIA/EIA-568-B.1-2001. The main difference between T-568A and T-568B is that the orange and green pairs are interchanged. See Figure 1.

RJ45 wiring standard

Figure 1. T-568A & T-568B Pinout Details

Ethernet Patch Cables VS. Cross-Over Cables

In simple terms, the main difference between Ethernet patch cables and cross-over cables is that each type will have different wire arrangement in the cable for serving different purposes.

Pinout Comparison
An Ethernet patch cable is an Ethernet network cable where both ends are wired to one of the specifications (either T-568A or T-568B), namely, both ends of it are terminated in the same standard. This is why a patch cable is also called straight-through cable. Nowadays, T-568B has surpassed T-568A and is seen as the default wiring scheme for twisted pair structured cabling. See Figure 2.

Ethernet patch cables

Figure 2. Ethernet Patch Cables-T-568A & T-568B

Warm Tips: If you are not sure of which to use, choose T-568B.

Unlike a patch cable, a cross-over cable uses two different wiring standards in termination. One of the ends uses the T-568A wiring specification, and the other end uses the T-568B wiring specification. This design allows the data output pins on one end of the cable to be connected directly to the data input pins on the other end of the cable. See Figure 3.

crossover-cables

Figure 3. Ethernet Cross-Over Cable

Applications Comparison
As mentioned above, Ethernet patch cables and cross-over cables are wired differently from each other. Thus, they have different applications. Patch cables are most commonly used and usually designed to connect different types of devices, such as computers to network devices like hubs, switches and routers. When we require to connect the same type of devices, such as connecting two computers directly, we will need a cross-over cable. Because using a patch cable to connect two computers means they will both be trying to transmit on the same cable. The following table shows the situations of using a patch cable or a cross-over cable.

Cable type Typical application
Patch cable (straight-through)
  • Switch to router
  • Switch to workstation or server
  • Hub to workstation or server
Cross-over cable
  • Workstation to workstation
  • Switch to switch
  • Switch to hub
  • Hub to hub
  • Router to router
  • Router to PC

Warm Tips: If the computer’s network adapters contain built-in cross-over support, like Gigabit Ethernet adapters, we can use a patch cable in this case.

Conclusion

Patch cables and cross-over cables are two types of Ethernet network cables. They are fundamentally different and designed for different applications. To determine if you have a patch cable or a cross-over cable, just compare the Ethernet cables to see if the colors are wired in the same order on each end. Always choose the proper cable depending on your applications. FS.COM offers a full range of colored Ethernet patch cables (straight-through) including Cat5e, Cat6, Cat6a and Cat7 to meet your network requirements. In addition, products such as patch panels, network tools/testers, Ethernet bulk cables and other cable assemblies etc. are also available in FS.COM. For more information, please contact us over sales@fs.com or by calling +1 (718) 577 1006.

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