Commercial CDN services are provided by a variety of companies, including "pure play" CDNs (of which Akamai remains the largest), telecoms network operators such as BT, AT&T and Telefonica, and relative newcomers to the CDN market such as Amazon and Google. Google already uses its own international CDN to distribute its YouTube video service. In addition, Google recently ventured into the market for commercial CDN services, in providing support for NBC's online coverage of the London 2012 Olympics.
Broadcasters are just one of several categories of company using CDNs for online content delivery. According to Chris Drake, a senior analyst at Informa Telecoms & Media covering the global CDN market, "CDN services are purchased by a plethora of businesses and other organizations that require an online presence, including broadcasters and social networking sites, software and gaming companies, e-commerce firms, financial services institutions and government, educational and public sector bodies.
"In order to serve the online delivery needs of their customers, CDNs use a range of techniques, including content caching, intelligent routing and traffic prioritization," Drake adds. "Techniques such as these help to mitigate problems such as network congestion, packet loss, traffic delay and jitter."
Although CDNs play an essential role in ensuring that the Internet works, the deployment of network-based CDNs by telecoms operators has fueled fears that these companies could use their position to distort the so-called neutrality of the Internet by prioritizing the delivery of their content and that of any other organizations willing to pay.
However, as Drake argues, "The Internet is already subject to extensive use of a wide array of traffic-management techniques by network operators. These include traffic shaping, by which operators manage the pressures of heavy Internet users on network resources, as well as efforts to block or restrict traffic that is harmful, illegal or undesirable, such as spam. These traffic-management techniques benefit broadband customers and, without them, end users simply wouldn't receive the standard of online experience they've come to expect.
"The widespread use of traffic-management practices by network operators raises questions about whether the Internet has ever been as open as net-neutrality proponents would like. The rise and rise of new operator and content-provider CDNs is just the latest illustration of ways in which the Internet is becoming less neutral."