Cat5e vs. Cat6 vs. Cat6a Cabling

What do Cat5e, Cat6, and Cat6a have in common?

They each utilize 4 twisted pairs in a common jacket. They use the same style RJ-45 jacks and plugs. And, they are each limited to a cable length of 100 meters including the length of the patch cables on either end of the link. The parts are interchangeable, so you can use a Cat5e patch cable with Cat6 house cabling. Your system will just perform at the level of the lowest link, in this case the Cat5e patch cable.

So what's the difference?

Better transmission performance. With each upgrade in cable, there is less signal loss, less cross talk, and more bandwidth. And of course, more cost. So the important question is: What exactly am I getting for my money? Rather than talk about near-end-cross-talk requirements or SNR ratios, let's talk about what each cable delivers in terms of Ethernet performance.

Cat5e:
Gigabit Ethernet up to 100 meters
10 Gigabit Ethernet up to 45 meters

Cat6:
Gigabit Ethernet up to 100 meters
10 Gigabit Ethernet up to 55 meters

Cat6a:
Gigabit Ethernet up to 100 meters
10 Gigabit Ethernet up to 100 meters

All three support gigabit, which is enough for most networks. 10 Gigabit, when it is deployed, is typically utilized for aggregation links between switches and not for workstations. Although it is unlikely an enterprise will require 10 gigabit to the workstations, certainly it is reasonable to design a new system with future needs in mind. In this case, the 10 gigabit capacities of Cat5e and Cat6 are problematic. Since data closets are located based on an assumption that workstation lines can be up to 100 meters, the shorter length limitation for Cat5e and Cat6 make them undesirable. That leaves Cat6a as the cabling of choice for future proofing.

So which cable should I use again?

Cat5e will give you all the performance you are likely to need today for workstations.

Cat6a could provide some future proofing, but there is currently nothing on the market that takes advantage of what Cat6a has to offer, and it's possible, that there never will be. I mean, when will we really need more than gigabit ethernet to a single computer?

What if I might use the cabling for something OTHER than Ethernet?

Unshielded Twisted Pair (UTP) cabling can also be used for analog transmission. When carrying broadband video (CATV), the cable performance has a big impact on signal quality and in turn, the length your cable runs can be. For these sorts of applications, Cat6 may have some value. Of course, Cat6a would be even better but Cat6a is relatively new and the price jump between Cat6 and Cat6a is much steeper than the difference between Cat5e and Cat6. Consult your specific application specifications to see what cable lengths are permitted for each type of cable.