Structured cabling categories explained

Ethernet cabling also known as structured data cabling often provides a faster, more reliable and longer-distance alternative to Wifi for commercial networking needs. But understanding the differences between Cat5 and Cat6 can be tricky if you’re new to structured cabling infrastructure; not helped by the fact that Ethernet cables from different categories often look identical, and even come with the same connectors.

So, what are cable categories? How can you tell the difference? And more importantly, why should you care?

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What are Ethernet cable categories?

Copper data cabling categories are simply manufacturing standards which define the data transfer speeds and reliability of each cable standard. The higher the number of the category, the higher the bandwidth; or in other words, the more data it can transfer per second.

Each new cable category is designed to eventually – but not necessarily immediately – replace the category that precedes it. That’s because cable categories are usually designed to handle more data per second than most consumers are currently using at the time of the category’s introduction.

This means that cables can remain useful even as consumers’ data needs evolve throughout the years.

More recent cable categories are also designed to minimise ‘crosstalk’; the signal interference that can occur between the pairs of twisted copper wires inside each cable, as well as the interference between cables and other nearby cables or devices.

Crosstalk can cause intermittent network slowdowns, connection dropouts and lost data; which is why later categories are designed with different twist rates and often include ‘shielding’ to prevent signal problems.

Why is choosing the correct Structured data cabling important for your business?

Well, choosing the right cables for a commercial network installation or revamp has a number of cost implications. You’ll need to balance your team’s current and future data needs with the economical needs of your company.

Each cable category has a maximum bandwidth. If your cables are slower than your current data usage, your network speed will struggle to keep up with your daily workload.
In addition, if your cables are slower than your other network equipment and/or the internet coming from your service provider, you’re effectively paying for a faster network than you’re actually receiving.
You should also keep in mind that each new hire will increase your overall data usage; so relying on older Ethernet cabling can hinder your company’s growth.
Crosstalk issues with older unshielded cables can also cause temporary downtime for your business; particularly if you’re limited on office space and need to run cables in close proximity.
Older cables may be cheaper to buy, but they’ll become obsolete and unfit for purpose much quicker. The cost and workplace disruption of stripping out and replacing outdated cables are far more impactful than the cost of buying a more advanced, future-proof cable category.
At the same time, the most leading-edge cable categories are not necessarily the most economical choice; particularly if you’re planning to move or expand your business to new premises within the next few years. You’re better off settling for a category somewhere between the two extremes.

Crosstalk issues with older unshielded cables can also cause temporary downtime for your business; particularly if you’re limited on office space and need to run cables in close proximity.
Older cables may be cheaper to buy, but they’ll become obsolete and unfit for purpose much quicker. The cost and workplace disruption of stripping out and replacing outdated cables are far more impactful than the cost of buying a more advanced, future-proof cable category.
At the same time, the most leading-edge cable categories are not necessarily the most economical choice; particularly if you’re planning to move or expand your business to new premises within the next few years. You’re better off settling for a category somewhere between the two extremes.

Cable categories explained

Cable categories have existed since the 1980s – but the purposes of this guide, we’ll be passing over categories which have already reached obsolescence and skip straight to…

What is Cat5 / Cat5e cabling?

Introduced near the turn of the millennium, Cat5e – or Category 5 Enhanced – is a revision to the original Cat5 cable standard which had been around since 1995.

Though the two cable types are very similar, Cat5e offers ten times the max data transfer speeds of its predecessor at 1 gigabit per second (or 1000 megabits a second) over a cable distance of 100 metres. Cat5e is also designed to reduce the chances of crosstalk compared to Cat5 for a more reliable connection.

All good so far, right? Unfortunately, multi-gigabit Ethernet connections have started rolling out across the UK, which Cat5e can’t support. It’s still very early days for the tech, but it does mean that Cat5e’s time will soon be up; with some cabling manufacturers already deciding to stop production on the latter.

Many businesses are still using Cat5e, but if you’re setting up the networking infrastructure for a new office, we’d recommend going with something a little more future-ready; such as…

What is Cat6 cabling?

Cat6 is the next category up from Cat5. It offers a max transfer rate of 10Gbps – ten times the rate of Cat5 – and comes with even better protection against crosstalk.

However, there are caveats to both. Cat6 cables don’t always come with shielding, and it can be tricky to tell the difference between shielded and unshielded cables. Cat6 is also more vulnerable to ‘alien’ crosstalk – interference caused by nearby devices or other cables – when operating at higher transfer rates.

More importantly, that 10Gbps transfer rate can only be achieved over a maximum cable length of 55 metres. Over 100 metres, the max rate drops to just 1Gbps.

Cat6 is backwards compatible with Cat5 equipment, and it’s a great choice for smaller offices – but for larger premises, you might be better off with the next category up…

What is Cat6A cabling?

Unlike its Cat6, Category 6 Augmented provides 10Gbps speeds at a cable length of 100 metres. It’s also backwards compatible with Cat5 and Cat6 equipment, and largely avoids the alien crosstalk problems of its older sibling; although again, Cat6A can come shielded or unshielded.

If you’re looking for the most economical balance of cost versus longevity for a larger workplace site, Cat6A is the option for you.

While we’re here, we should mention Cat6e (or Category 6 Enhanced). Technically, this isn’t an official standard, but some cable manufacturers still produce it. So what exactly is it?

Cat6e simply means that the cable exceeds the official specifications for Cat6 cables. In practice, this usually means it closely matches the performance of a Cat6A cable; but it’s always better to choose the clearly defined 6A over the mystery meat of 6e!

Beyond Cat6A

Data cabling standards get a little stranger after 6A…

Cat7 actually appeared before Cat6A and comes with similar specs to the latter, with guaranteed crosstalk shielding as a bonus; but it has different connectors than most Ethernet cables, which makes it less useful outside of certain server room applications.
Cat7A was designed to handle potential future internet speed standards of 40Gbps; but with Cat8 effectively replacing it, most 7A-compatible equipment won’t be able to run the cables faster than Cat7’s 10Gbps limit.
Cat8 are backwards compatible and offer the capacity for true 40Gbps network performance; but again, it’s designed for data centres rather than office cabling requirements. Most offices won’t need anything close to 40Gpbs, so you’re better off with 6A for the time being.

Any questions?

We hope we’ve demystified the concept of copper data cabling categories for you! To summarise; Cat5e is fine for now but isn’t recommended for new installations, while Cat6 is a great choice for smaller offices, and Cat6 is the most economical yet future-proof solution for larger business premises.

Need a hand with your structured cabling installation project? JC Electrical can provide tailored project planning and installation for all kinds of copper network cabling and even fibre cabling requirements. Take a look at our Data Cabling page or get in touch to find out more!