The People & Machines That Bring VOD to Our Screens - Stephen Wills
Level 3 Communications provide a portfolio of co-location, internet, fibre-based transmission, voice, and content and media telecommunications services.
In addition to supporting traditional telecommunications transport and IP services, Level 3 Communications' fibre-based transmission and IP networks also provide the lower network layers upon which streaming media, content delivery and broadcast services are supported. Typically, each of its backbone fibre routes consist of one or more fibre cables, with each cable consisting of multiple fibre pairs. Using Level 3 transmission equipment in service today, each fibre pair can support as much as 3.2T bit/s of data.
Fiber optics is basically the transport layer for all internet traffic and that really is the core part of Level 3's business. We provide facilities to companies to allow them to retail internet access to the consumer or to businesses.
Level 3's Broadcast Services are supported using its Vyvx Broadcast Network. A number of broadcasters are connected directly to our London node and we carry a lot of broadcast traffic related to specific events. For example, with the Royal Wedding, live television signals from outside broadcast trucks in Westminster were fed to Level 3's London Vyvx Node. From here the live feeds were distributed using the Vyvx Broadcast Network to a number US and Canadian broadcasters.
Level 3's Content Delivery Network is a vast system of interconnected servers that are clustered together in Level 3 datacentres across the globe. These servers store and deliver content (music, movies, software, documents) directly to end-users.
Level 3 provide a range of fixed rate and adaptive streaming media services. We can encode to pretty much any format the customer needs from fixed-rate Adobe Flash and Windows Media, to adaptive Microsoft Silverlight Smooth, HTTP Adaptive (which is used by iPhones and iPads) and Adobe Dynamic. Basically, whatever your device and operating system, we can get content to it.
Up till a couple of years ago everything was fixed rate. That meant that if your broadband was a bit slow you might see a lot of buffering when you were trying to watch a video - your PC was trying to play something that it didn't quite have enough power to handle.
Nowadays, with adaptive bit-rate technology, rather than encoding and delivering the video content as a single fixed rate stream, the source video is encoded into multiple streams at varying rates from low to high. All these bit rates are then made available for delivery to the end user.
Intelligence within the end users PC or mobile playback device effectively "tests" the delivery bandwidth and the processing power available, and selects the most appropriate bit rate for playback. This test is performed every 2 seconds to ensure that we're sending you the most appropriate stream. For an end-user the experience is seamless and hopefully, buffer-free.