What are the differences between CAT5E and T568A vs. T568B for ethernet cables?

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In summary, the connector standards for CAT5E are transparent to the hardware being connected so long as one preserves the standard (and gender?) at both ends of a cable run. Net sites discussing A & B include caveats regarding mixing; A won't work with B, and vice versa, with comments that video goes to hell, or other nagging problems, intermittents, sensitivity to phases of the moon, you name it.
  • #1
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Searching "t568" doesn't bring up any matches: presumably the topic ain't been covered.

As far as stringing ethernet cables, T568A and T568B connector standards for CAT5E are transparent to the hardware being connected so long as one preserves the standard (and gender?) at both ends of a cable run. Net sites discussing A & B include caveats regarding mixing; A won't work with B, and vice versa, with comments that video goes to hell, or other nagging problems, intermittents, sensitivity to phases of the moon, you name it.

The questions: has anyone ever had such problems; and, does anyone know physically what's happening to signals?
 
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  • #3
OK. thankee.

For the interested, U. S. recommends A for residential wiring, B is the common use item, and B is what you get at the village drugstore when you ask for ethernet patch cords.

A on one end, B on the other, same gender both ends works for tying two computers together.

Hermaphrodites (different genders on ends of cable) are what causes trouble in "mixed" systems.
 
  • #4
although I don't follow you completely, I would like to specify a couple things that confused me. t568A and t568B are 2 different wiring standards used in cat-5 cable. Normally, t568B wiring is used, but t568a wiring also works.
If you use a cable with t568B on one end and t568A on the other, you'd have
an ethernet crossover cable, used for a NIC2NIC network connection.
I would assume that with just switching the wiring on one end of a cat-5 cable to the other type, you can make a cat-5 cable act as an ethernet crossover cable, however, I have not tried myself (I have used a prefab ethernet crossover cable between 2 NICs and it worked)
 
  • #5
The colours mean nothing as long as you have the correct pin outs at both ends...

Code:
100BaseTX RJ-45 Connector

The Fast Ethernet RJ-45 port actively terminates wire pair 4 and 5 and wire pair 7 and 8. Common-mode termination reduces electromagnetic interference (EMI) and susceptibility to common-mode sources.

The table below shows the pin and corresponding signal for the RJ-45 connector pinouts.

RJ-45 Connector Pinout

Pin
	

Signal

1 TX+

2 TX-

3 RX+

6 RX-

http://www.cisco.com/en/US/products/hw/routers/ps133/products_tech_note09186a00801f5d9e.shtml
 

1. What is CAT5E?

CAT5E is a type of Ethernet cable commonly used for internet connections. It stands for Category 5 Enhanced and is an improved version of the original CAT5 cable. It supports data transfer speeds of up to 1000 Mbps and is suitable for most home and office networks.

2. What is the difference between T568A and T568B?

T568A and T568B are two different wiring standards for Ethernet cables. They differ in the order in which the wires are connected to the connector. T568A has the green and orange pairs in the middle, while T568B has them on the outer edges. Both standards work equally well, but T568B is more commonly used in North America.

3. Can I use T568A and T568B together?

No, it is not recommended to mix T568A and T568B standards in the same network. This can cause confusion and connectivity issues. It is best to choose one standard and use it consistently throughout the network.

4. Which standard should I use for my network?

It is generally recommended to use T568B for your network, as it is the most widely used standard in North America. However, if you are setting up a network in a different region, it is best to check which standard is commonly used there.

5. Do I need CAT5E cables for my network?

If you want to have a reliable and high-speed internet connection, then yes, it is recommended to use CAT5E cables. They are designed to support faster data transfer speeds and provide better performance compared to older types of Ethernet cables.

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