This question comes up all the time. “Should we use Cat6 or Cat6A for our structured cabling plant?” You may have already guessed that the answer, as with most technology decisions, is that it depends. The correct choice for you will depend on your particular application as well as your long-term needs.  

Similarities

• Both support up to 1gig to 100 meters. 

• Both support 10gig.  

• Both support power over ethernet (PoE).  

• Both have jackets made for different installation needs – such as riser-rated.  

• Both can be shielded or unshielded.

Differences

• Cat6A is made with higher tolerances than Cat6.  This means that the twists are tighter to meet higher specifications. This also means the terminations require Cat6A parts.  

• Cat6A speed is at least 500MHz.  This provides 10gig up to 100 meters.  Cat6 speed is only 250MHz, which only provides 10gig up to half the distance (around 55 meters). 

• Cat6A uses thicker copper conductors and jackets.  This means it can support higher PoE wattage requirements (up to 100w), but it also makes the installation a bit more difficult which can add cost.

So which should you choose?

  Here are some things to consider: 

• Will you have a need for 10gig to the desktop in the next 10 years?  

• What are your PoE requirements going to be in the future? Remember that there are many kinds of IoT devices now that support PoE but require higher wattage. Many devices—including access points, digital signage, video conferencing systems, and laptops—are becoming capable of pulling power from PoE switches.   

• If your PoE requirements will be going up, then you will want thicker cable to help dissipate the heat and prevent power loss over distance, which Cat6A will provide.

Inside the data center, using either Cat6 or Cat6A will work because there usually isn’t a long distance between devices or a need for PoE. Outside the data center, the choice becomes harder because you have to predict what your needs will be many years in the future.   

If you are putting in a new cable plant, our suggestion is to consider Cat6A because that will give you the longest life and there is a good chance that you will want to start using devices that have high PoE requirements that only Cat6A can support over distance. If you have an immediate need for some devices that require 10gig or have high PoE requirements, you can start running Cat6A to support these devices.  

When should you choose Cat6?  It would seem that unless you definitively know that you will not have any high PoE requirements, or will not need 10gig at maximum distance (100 meters), then you could choose Cat6.  But that’s a tough call to make. Ultimately, if Cat6A is not in your budget and you have no immediate need for Cat6A, then budget will be the deciding factor. Cat6A materials cost about 3x what Cat6 material costs and depending on the size of your project that can be pretty significant.  However, you should weigh this against your long-term strategy. A 25-year warranty is lengthy, and if you plan to be in the same building for more than 7 years, Cat6A is worth considering for investment protection.