Why is this a concern for ISPs? Netflix says that in order to enjoy a streaming 4k signal that a user ought to have a spare 15 – 20 Mbps of bandwidth available if streaming with buffering. The key word is spare, meaning that any other household activity ought to be using other bandwidth. Netflix says that without buffering that a user ought to have a spare 25 Mbps.
When we start seeing a significant number of users stream video at those speeds even fiber networks might begin experiencing problems. I’ve never seen a network that doesn’t have at least a few bottlenecks, which often are not apparent until traffic volumes are high. Already today busy-hour video is causing stress to a lot of networks. I think about millions of homes trying to watch the Super Bowl in 4K and shudder to think what that will mean for most networks.
While 4K video is already on-line it is not yet being offered by cable companies. The problem for most of the industry is that there is no clear migration path between today and tomorrow’s best video signal. There are alternatives to 4K being explored by the industry that muddy the picture. Probably the most significant new technology is HDR (high-dynamic range) video. HDR has been around for a few years, but the newest version which captures video in 10-bit samples adds both contrast and color accuracy to TVs. There are other video improvements also being explored such as 10-bit HEVC (high-efficiency video coding) which is expected to replace today’s H.264 standard.
The uncertainty of the best technology migration path has stopped cable companies from making upgrades to HDR or 4K. They are rightfully afraid to invest too much in any one version of the early implementations of the technology to then face more upgrades in just a few years. But as the popularity of 4K video increases, the pressure is growing for cable companies to introduce something soon. It’s been reported that Comcast’s latest settop box is 4K capable, although the company is not making any public noise about it.
But as we’ve seen in the past, once customers start buying 4K capable TVs they are going to want to use them. It’s expected by 2020 that almost every new TV will include some version of HDR technology, which means that the quality of watching today’s 1080 pixel video streams will improve. And by then a significant number of TVs will come standard with 4K capabilities as well.
I remember back when HD television was introduced. I have one friend who is a TV buff and once he was able to get HD channels from Comcast he found that he was unable to watch anything that was broadcast in standard definition. He stopped watching any channel that did not broadcast HD and ignored a huge chunk of his Comcast line-up.
The improvements of going to 4K and/or true HDR will be equally as dramatic. The improvement in clarity and color is astonishing as long as you have a TV screen large enough to see the difference. And this means that as people grow to like 4K quality they will migrate towards 4K content.
One thing that is clear is that 4K video will force cable companies to broadcast video over the IP stream. A single 4K signal eats up an entire 6 MHz channel on a cable system making it impossible for any cable system to broadcast more than a tiny number of 4K channels in the traditional way. And, like Comcast is obviously preparing to do, it also means all new settop boxes and a slew of new electronics at the cable headend to broadcast IPTV.
Of course, like any technology improvement we’ve seen lately, the improvements in video quality don’t stop with 4K. The Japanese plan to broadcast the 2020 Olympics in 8K video. That requires four times as much bandwidth as 4K video – meaning an 80 – 100 Mbps spare IP path. I’m sure that ways will be found to compress the transmission, but it’s still going to require a larger broadband pipe than what most homes buy today. It’s expected that by 2020 that there will only be a handful of users in Japan and South Korea ready to view 8K video, but like anything dramatically new, the demand is sure to increase in the following decade.