Akamai Technologies is now delivering HD quality video content for its customers via its distributed edge delivery network with servers in more than 750 cities worldwide. For the Internet, Akamai said it is making the HD web possible by continuing to refine the infrastructure required to bring the HDTV experience to online audiences. 
HDTV is defined as pixel resolution of 1080i, 1080p or 720p. A 2-hour feature-length movie would need to be encoded at a bit rate of at least 6-8 Mbps, which would result in the file being a size of 5-8 GB. This presents numerous technical challenges to deliver such a high-quality, large file.
Akamai calculates that to deliver a file encoded at 6 Mbps to an audience of one Nielsen ratings point (1,102,000 households) would require 6.6 Terabits of sustained bandwidth. Another critical factor to enable high bit rate delivery of very large HD files is the proximity of the end-user to the server sending the file. As the distance from the server becomes greater, throughput dramatically decreases. Even a seemingly small distance can result in lost throughput due to lower throughput, higher packet loss, and increased latency. As an example, the only way to achieve 10 to 20 Mbps throughput for typical PC end-users is if the server is less than 20 milliseconds away.
Akamai has architected its platform to comply with the following technical criteria that content owners must leverage to successfully enable an HD web:
- Technology and an operational model to operate serving devices in the largest high-throughput networks around the world (servers need to be physically in the networks, as that is where the capacity lies)
- Established relationships with the largest high throughput networks
- Support for delivery, storage, and management of files greater than 2 Gigabytes
- Support of VC-1 and MPEG-4 video standards, achieving visual parity with other broadcast video networks
- Support for files with resolutions of 720p, 1080i and 1080p
- Client-side technology that is deeply integrated into its delivery system to be deployed as appropriate.
Additionally, Akamai plans new service launches, device integration, and partnerships with technology vendors in the coming months.
http://www.akamai.com
