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Cat6 and Cat6A look similar on a spec sheet, and both terminate on an RJ45 jack. The differences show up in three places: how fast a link can run over a full-length channel, how the cable handles heat from Power over Ethernet, and how much room it takes in pathways and racks. Choosing the right category is a question of what each drop will carry over the life of the cabling, not just what it carries on day one.
The short answer
- Specify Cat6A for wireless access points, for high-power PoE devices, and anywhere 10 Gb/s may be needed over long runs
- Cat6 remains a reasonable choice for desktop, phone, printer, and POS drops in most commercial spaces, where speeds above 1 Gb/s are unlikely to be needed
- Do not mix categories within a link: a Cat6A cable terminated on Cat6 jacks performs as Cat6
Bandwidth and speed
Category 6 is specified to 250 MHz and Category 6A to 500 MHz under ANSI/TIA-568.2-D. The extra bandwidth matters for 10GBASE-T. Cat6A supports 10 Gb/s over the full 100-meter channel. Cat6 supports 10 Gb/s only over shorter distances, commonly quoted at up to 55 meters, and even then performance depends on alien crosstalk between neighboring cables in a bundle.
Between 1 and 10 Gb/s sit the NBASE-T speeds defined in IEEE 802.3bz. 2.5GBASE-T was designed to run over Cat5e and 5GBASE-T over Cat6, both to 100 meters in typical installations. Many current access points and switches use these speeds, which is one reason Cat6 is still a working choice for some uplinks. 10 Gb/s to the edge over a full-length channel, though, needs Cat6A.
Distance
For both categories, the standard channel is 100 meters: a permanent link of up to 90 meters from the patch panel to the outlet, plus up to 10 meters of patch cords at both ends. Anything longer needs a closer telecommunications room, fiber, or a powered device in between. Plan closet locations early on large floors and warehouses, because the 90-meter permanent link limit often decides where an IDF has to go.
Power over Ethernet and heat
IEEE 802.3bt allows up to 60 W (Type 3) and 90 W (Type 4) at the switch port. Current flowing through a cable produces heat, and in large bundles that heat builds up, raising cable temperature and increasing insertion loss. Cat6A cable is typically larger in construction and generally handles heat in large bundles better than Cat6. TIA publishes guidance on PoE bundle sizes and temperature rise, and it is worth reviewing for any design with many high-power devices in one pathway.
Cameras with heaters, multi-radio access points, digital signage players, and some building devices draw more power than a desk phone. If a drop may power one of these devices in the next several years, it is a candidate for Cat6A.
Pathway space and installation
Cat6A is noticeably larger and stiffer than Cat6. It takes more room in conduit, J-hooks, cable trays, and patch panels, and it needs more care to maintain the minimum bend radius, which for unshielded twisted pair is four times the cable diameter. Plan for:
- Larger or additional conduit and J-hook capacity
- Fewer cables per bundle and per pathway
- Rack space and cable management for heavier patch fields
- More labor per drop, because the cable is harder to pull and dress
Shielded Cat6A, such as F/UTP, adds a foil that reduces alien crosstalk but must be bonded and grounded correctly to work. Unshielded Cat6A is widely used in commercial buildings. Follow the manufacturer's system requirements for whichever you choose.
Components must match
A link performs only as well as its weakest component. A Cat6A installation needs Cat6A cable, jacks, patch panels, and patch cords from a system rated to work together. Mixing a Cat6A cable with Cat6 connectivity produces a Cat6 link and, if certified to Cat6A limits, failing test results.
Testing and certification
Ask for certification test results for every link, not just a continuity check. Certification measures parameters such as insertion loss, crosstalk, and return loss against the limits for the category. For Cat6A, use a field tester that meets at least Level IIIe accuracy under ANSI/TIA-1152-A. Specify whether you want permanent link or channel testing, and ask for the results in the tester's native file format as well as PDF so they can be archived and re-read.
Which to choose, drop by drop
- Wireless access points: Cat6A. Industry guidance for access point cabling generally recommends it, and current APs increasingly use multi-gigabit uplinks and higher PoE budgets
- Security cameras: Cat6 for most fixed cameras, Cat6A for high-power PTZ cameras or long runs in large bundles
- Desktops, phones, printers, and POS: Cat6 is usually sufficient
- Digital signage: Cat6 for most displays, Cat6A where a player is powered over PoE or 10 Gb/s is planned
- Backbone between closets: fiber for long runs; Cat6A for short copper links where 10 Gb/s is needed
What to put in the specification
- Category for each drop type, and the connectivity system to be used
- Plenum or non-plenum rating based on the space
- Pathway type and support method
- Labeling scheme for outlets and patch panels
- Test level, test type, and report format
- As-built documentation requirements
Relion technicians install and test network cabling to the specification you provide, and return test results with the closeout package. For access point drops, see also Wi-Fi and access point installs.