Crossover and Straight Through Ethernet Cables Defined

Twisted-Pair Ethernet cables such as the Cat6a, Cat6, and Cat5e are differentiated from one another in a multitude of ways. The first feature is their category. It defines the performance specifications of the cable. Then comes the plenum and riser ratings which determine where the cable will be installed. For example, the Cat6a plenum will be installed in indoor vertical runs and the Cat6a riser cable in indoor vertically rising spaces.

There are two very important specifications of the cable that are not readily known in the industry like the ones we mentioned. So much so that most of the time, the average user does not even know what type of cable they are using. These specifications are called straight through and crossover.

Straight through and crossover are two types of terminating cable conductors in the RJ45 connectors and keystone jacks. The way conductor wires are terminated in the jack or connector defines how the cable is used. Straight-through Ethernet cables are patch cables that are used to connect different devices in Local Area Networks.

Crossover cables are twisted-pair cables that are used to connect the same devices in LANs. A PC to a PC for instance will be connected using a crossover cable whereas a PC will be connected to a router using a straight-through cable. In this blog, we will introduce you to crossover and straight-through ethernet cables. We will also enlist the differences between the crossover and straight-through cables as well as the best options to choose from.

 

Why Learn About Straight Through and Crossover Cables?

As mentioned earlier, the straight-through and crossover are two lesser-known features of ethernet cables. Knowing what these features are is crucial to getting the right cables. For example, if you are buying or installing ethernet cables for the first time, you will need to make sure that you are getting the right ones for the right application.

If you are installing ethernet cables for the first time, you need to know how to terminate the cable conductors into connectors and jacks. And knowing what these cables are will provide you with the information that you need to terminate your cables correctly. There are basically two standardized methods of terminating the cable conductors known as ANSI/EIA/TIA T568 A and T568 B. More on that later.

 

Crossover Cables

Crossover cables are the cables that you use when you need to connect a computer to a computer, a switch to a switch, a router to a router, etc, etc. This type of cable is defined by the fact that its ends are configured into jacks and connectors as per different wiring standards. If one end of the cable is configured according to the T568A standard, the other end will be configured according to the T568B standard.

Different types of wiring configurations on both ends of the crossover cables are followed because of their use. Since crossover cables are used to transfer data between similar devices, it is important to reverse the transmission to receive the signals. And the reversal of the transmission is achieved by following different wiring standards on both ends of the cable.

 

End One (T568B)

 

    1. White Orange
    2. Orange
    3. White Green
    4. Blue
    5. White Blue
    6. Green
    7. White Brown
    8. Brown

 

End Two (T568A)

 

    1. White Green
    2. Green
    3. Orange White
    4. Blue
    5. White Blue
    6. Green
    7. White Brown
    8. Brown

 

Straight Through Cables

The common definition of straight-through cables is that they are used to connect different electronic devices in a network. And the more technical definition is that straight-through cables are terminated using the same ANSI/EIA/TIA standard on both ends of the cable. For example, if one end of the cable is terminated as per the T568A wiring configuration, the other end will also be terminated as per the same configuration.

In the example below, the end of one of the cables is terminated as per the T568B wiring standard.

 

End One (T568B)

 

    1. White Orange
    2. Orange
    3. White Green
    4. Blue
    5. White Blue
    6. Green
    7. White Brown
    8. Brown

Similarly, the second end of the cable is also terminated as per the T568B. Note that you can use either of the two ANSI/EIA/TIA wiring standards. Just be sure to use the same on both ends of the cable.

 

End Two (T568B)

 

    1. White Orange
    2. Orange
    3. White Green
    4. Blue
    5. White Blue
    6. Green
    7. White Brown
    8. Brown

 

Straight-Through or Crossover Cable: Which Ones To Use?

Your options are determined by the type of application. If you need the cable to run between the plenums and risers to connect devices to your router or server, you will need to use straight-through cables. On the other hand, if you need a cable to connect devices to similar devices, you will need to use the crossover cable. These cables have longer lengths as compared to the straight-through cables and you will need to terminate them yourself. Whereas the straight-through cables come with preloaded RJ45 connectors and are much less work.

Pro Tip: You can make your own straight-through cables using the crossover ones. You will need to buy an ethernet cable such as a Cat6a with a couple of RJ45 Keystone Jacks. Once you have the jacks and the cable, cut the cable at the length you require. Then terminate the connectors as per the T568A wiring configuration on one end and the T568B on the other.

 

Difference Between Straight Through and Crossover

Crossover and straight-through cables are two different types of cables. Both types are different because of different internal wiring configurations. Crossover cables are used to connect devices of the same nature (PC to PC, Router to Router, Switch to Switch, etc), whereas straight-through cables are used to connect devices of different natures (PC to Router, Hub to Router, Hub to PC, etc). For example, if you need to connect all the computers in your office, you will use a crossover cable, and to connect the computers with a hub, a switch, or a router, you will need to use a straight-through cable.

 

The Need for Crossover Cables

The debate around the need for crossover cables has been going on for some time now. Some people are of the opinion that straight-through cables have eliminated the need for crossover cables. But crossover cables are still very much essential parts of LAN networking because of their immense significance. To connect a router and a computer, you need a crossover cable. Similarly, you need these cables for all connections of different natures. A computer can indeed be connected to a router wirelessly, but such connections are unreliable and are susceptible to being breached by hackers. Connections over these cables ensure high performance in addition to security.

 

ANSI/EIA/TIA T568 A vs T568 B

T568A and T568B are the two wiring standards set by the ANSI/EIA/TIA. Its purpose is to regulate the internal wire configuration of twisted pair ethernet cables. Both standards also find their use in straight-through and crossover cables.

 

Best Crossover Cables to Buy

The following are some of the best crossover ethernet cable options that you can buy today. Note that these cables are ideal for use as a crossover but you can also make straight-through cables out of them. It depends on how you terminate the ends. All of them are bulk (1000ft) cables and are being offered at market competitive prices.

 

    • Cat6a Plenum
    • Cat6 Plenum
    • Cat6a Riser
    • Cat6 Riser

 

Best Straight Through Cables to Buy

Best straight-through cables do not have to be lengthy like the bulk cables. In fact, straight-through cables have to have short lengths in order to function at their optimum. The following are the best options you can buy.

 

    • Cat6 Patch Cable 550MHz Best in Blue Color
    • Category 6 Patch Cord UTP 550 MHz Gray Cable
    • Cat6 Patch Cord Black High Quality 550 MHz
    • 1-feet Cat6 Solid Copper Patch Cable in Multi Colors Pack of 10