The quantity of video being delivered through broadband connections, rather than cable, satellite or OTA, is mushrooming as more television sets gain an Internet connection, and Internet STBs cater for the older sets. OTT delivery is taxing existing broadband networks. Recent figures from Netflix illustrate the problem. In the U.S., real download speeds for video content average around 2Mb/s, much lower than the headline rate of the services. This is typical of many parts of the world. The ISPs have long convinced the viewer that a 20Mb/s service is just that; it's only the fine print that explains about contention, network congestion, etc.
Viewers now expect all manner of content to be delivered on-demand, either from the “walled garden” of their cable or IPTV supplier, or OTT from the Internet. Across the world, telcos are installing fiber to the cabinet, or even to the premises. Fiber can deliver much higher download speeds, assuming the backend infrastructure is also expanded. As these fiber services roll out, any provider that tries to cap data transfer or continues delivering low data rates is going to lose customers to other providers that can deliver higher performance. This demand for video is not going away.
The lowering of cost and the move to uncapped usage parallels the evolution of voice traffic. Once, local calls were metered, and international calls had to be booked through the operator. Now, flat-rate national calls are commonplace, and VoIP is popular for internal phone systems of corporations spread across multiple sites. National PTTs often held up progress, but local-loop unbundling has introduced competition, driving the technology and the offerings to the public.
However, fiber and routers alone do not make for efficient delivery of content. Hauling files across the globe, via different operators and fiber networks, needs intelligent content delivery management overlaid on the physical layer.
Luckily, viewers are not just consuming long tail content — far from it. Time-shifted viewing of the top-rated programs is just as popular. “I want to watch it when I want, not when the channel controller schedules it.” It is this behavior that offers some relief in the need for network bandwidth. If everyone is watching the same top-rated programs, usually within a day or so of first airing, then some smart edge caching can take a lot of traffic off the Internet.
What do you cache and where? Content delivery networks have been used for a decade to deliver Web content efficiently. The latest challenge is to deliver video efficiently. The large files and high stream rates both present challenges. Increases in network capacity can be consumed by the increase in video resolution. One-quarter SD resolution over the Internet has been replaced by 720p, with 1080 lines and 4K emerging.
As tablets become as popular for viewing as TV receivers, demand for OTT is escalating. Plus the tablet can also be a second screen, offering new ways to interact and view. It can be used as an EPG and remote for the display of additional content. It can be used to interact with social media related to the program being viewed. It can also show different video content. This could be different camera angles in genres like sports, or all manner of information and statistics. The tablet can also be used to view programming in its own right. With some new smartphones, you can mirror the screen with a TV to share mobile video. All these new ways to view add to the demands on the broadband connection.
The old chain of STL, tower and yagi is being supplanted with a whole set of new technologies, borrowing heavily from data routing practices. But adding the secret sauce of the media delivery network management layer is vital to delivering the QoS that viewers expect.
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