As screen resolutions increase from HD to 4K to 8K the pressure on the communications ‘pipe’ connecting source to screen will increase. Much can, and has, been achieved with compression, but where video needs to be transmitted uncompressed the bandwidth of the network infrastructure needs to be increased in direct proportion to the resolution of the images or video.

With 4K screens already coming down in price, installers should very much be thinking of the future rather than today’s needs when pulling new cable. The question to ask is not “what bandwidth is sufficient to support today’s needs” but “what bandwidth will be required next year and the year after that”.

Data bandwidth trends

Let’s take a look at current and forthcoming display resolution standards in this context, and consider what connectivity speeds might be required (Table 1).



Raw image bandwidth

inc. blanking, 4:4:4, 24bit

Best-case loss-less bandwidth

(1% overall blanking), 4:4:4 24bit





















Table 1 – bandwidth and resolutions

Clearly the likely date of adoption of the higher resolutions will vary from site to site. Whilst a premium hotel or corporate headquarters will move to the highest resolution as soon as it becomes available, other establishments will wait for screen prices to become more affordable. That said, each of these technologies will reach a tipping point at which they will become the norm. If a site is cabled to support higher resolutions, then upgrading is a matter of swapping out the source and the screen.

If it is not, then the cabling will need to be renewed completely – a very much greater investment. So let’s look at the major connectivity options in that context (table 2).

Performance comparison for the major infrastructure technologies


Max Bandwidth

Max Range

Standard HDBase-T


100 metres (320 feet)

Long reach HDBase-T


150 metres (500 feet)



55 metres (180 feet)

Multimode Fibre (OM-4)


150 metres (500 feet)

Singlemode Fibre (OS1)

100Gbps and up

Several 100Km (62 miles)

Table 2 - performance comparison for the major infrastructure technologies

Whilst there is a lot of buzz around HDBase-T technology at the moment, it should be considered a cost-effective rather than a future proof solution. Today, it is limited to 4K at 30 frames per second (fps). High performance copper does better and can support 4K at 60fps today. To provide a site with a pipe that will not only support all data requirements today but in the foreseeable future, the only technology in the game is fibre.

Let us look at each of the alternatives in detail.


The major selling point for HDBase-T is that it can be implemented over existing Cat 6 Ethernet cabling, and that the end-points are low cost. If using HDBase-T means you can avoid recabling a site then it is an attractive option, providing you accept its limitations in terms of range, performance and longevity.

What are these limitations? HDBase-T makes use of standard CAT5e/6 cable network infrastructure but it does not, of course, make use of Ethernet protocol, including the error correction mechanisms. For all HDBase-T devices, the range given in the datasheet should be regarded as the maximum that can be achieved rather than an absolute that will always be delivered. So much depends on environmental factors: the amount of electrical noise in the environment (including the number of other links nearby), the quality of the cable, how well it has been laid and terminated etc.

When installing HDBase-T, bear in mind that so called ‘long reach’ devices are likely to perform better and more reliably than standard implementations in most real world environments. Although all are built around the same Valens chipset, the firmware that runs on the chips is developed individually by each vendor. To achieve a longer range, a vendor will have tweaked that firmware to reduce the heat emitted in the design which will reduce the level of EMI emissions as well as the susceptibility to outside EMI. The result is that if you’re installing even a short (30 metre say) link in a ‘noisy’ environment like a lift shaft, the ‘long range’ product may deliver a reliable connection where a standard product will struggle.

High performance copper

HDBase-T is on paper a very cost-effective way of transmitting uncompressed video, but the savings made on the cost of hardware can quickly evaporate if additional time is required on site to trouble shoot the installation. In many environments, it is still well worth considering established alternative copper-based technologies. Although the end points will be more costly, it is often possible to compensate for this as they will run reliably over lower specification cable.

A further consideration is the flexibility on offer. As discussed above, the 100 metre range of standard HDBase-T is a maximum. So what if the ideal location for the display is 110 metres from the source? A reliable connection will almost certainly involve splitting the run with a booster along the way, which could be enough to change the economics balance on the hardware equation.

The case for fibre

Whilst it is likely that HDBase-T and other copper based technologies will be enhanced in the future, fibre is the only pipe that you can lay today that is wide enough to support all video standards currently under discussion. Fibre supports 8K now, and its speed too is likely to increase.

There is a lot of unnecessary fear around pulling fibre. Improvements in technology and materials make it much easier to install and terminate than it has been in the past. Modern fibres no longer need the very long bend radiuses required in the past. The author has seen demonstrations from Cleerline, a fibre manufacturer, who have tied knots in their fibres, and pulled them tight and still delivered clear transmissions through them.

Fibre is also no longer fragile. It is hard to break, and if it does break, the shards aren’t sharp. Using the Cleerline fiber, you’ll have trouble piercing your skin.

Compression terminations make reliable connections as easy to achieve as fitting a standard BNC connector, and does not require costly equipment. Just cut the fibre as required and push into the termination. It takes less than a minute.

The advantages of fibre are huge. Transmissions are completely unaffected by electrical noise, and generate no EMI themselves. The range and bandwidth is only limited by the performance of the lasers at either end. The transmission distance achievable is longer than is likely to be required on campus locations, and the speed exceeds that required for 8K.


Whilst copper based technologies like HDBase-T have a place, installers need to ask themselves serious questions before pulling copper cable on a new site – especially where they have the luxury of accessing the premises during construction. Fit copper today, and in two, three or four years’ time, the building may need rewiring. Fit fibre, and the customer will likely never have to upgrade the connections in the building again.