Content Delivery Networks
Date: Tuesday , February 01, 2005
For many in India, who believe that the Internet is just a surfing, chat or email enabler, the Tsunami was an eye opener of sorts. It established itself as the most available and easily accessible two way communication channel as people posted bulletins on lost family members, hospitals became accessible by the Internet gateway and not just the limited entrance doorway and help in the form of donations poured in from all corners of the growing-smaller-by-the-minute world.
As the rest of the world has already begun to acknowledge, the Internet’s potential is not just limited to large-scale disasters. As Broadband communication grows in importance in India, the Internet and the World Wide Web will also, certainly, find an expanded user base. The country has about 25-30 million Internet subscribers, and the government is hoping to boost the number to 40 million by 2010 in a population of more than a billion.
What’s ironical is that when a large number of people visit a site, the site experiences performance degradation. Exasperated messages saying, “Why is the Internet so slow?” also abounded on the news bulletins, soon after the Tsunami tragedy. The reason? The server, which is powering the site, cannot handle more traffic than what it has been provisioned for. Thus, to have a good presence on the Web, service providers should plan for networks, which will deliver consistent high performance while ensuring that requirements such as scalability, robustness, reliability, affordability and manageability are also addressed Having said that, one needs to understand that to deliver a robust, reliable, high performance web site, companies will have to invest heavily in their own network infrastructure: load balancing for nonstop delivery, caching for speedy Web response, distributed, replicated servers to limit the impact of Internet congestion and managing upstream bandwidth. Companies have to strike a delicate balance between customer satisfaction and cost.
If every CTO decided to invest in his own infrastructure to manage Web site performance, the costs are likely to be prohibitively high bringing his ROI down substantially. So, does this mean that the much-awaited Broadband era is going to see a few isolated large players investing heavily to have a great Internet presence? If that were so, then would the Internet with its huge potential continue to remain the privilege of a few?
As more and more businesses are coming to realize, like Fox Broadcasting did during the telecast of American Idol- the show which attracted 26.5 million viewers, it would not be economically viable to provision for not-so-regular large spikes in Web traffic. They instead opted for a Content Delivery Network service provider that could scale on demand and deliver consistent performance of their Web site by using a distributed network of servers to deliver their Web pages and streaming media clips.
The very recent Tsunami tragedy saw Unicef’s Web site rising up to the occasion with videos and photographs of the affected areas as well as the rehabilitation efforts in the Tsunami torn areas being posted on their Web site. For Unicef, which is not in the business for profit, investing in infrastructure to service such unprecedented events would prove to be financially challenging. They too, have efficiently, turned to the services of a CDN provider, whose giving back policy has ensured that all of Unicef’s worldwide Web site visitors get an excellent performance from their Web site.
Sudden spike in web site traffic is not necessarily limited to disasters or entertainment as can be seen in the case of NASA. When NASA launched its twin Mars Exploration Rovers, it set more than one record soaring, as its Web site received more than four billion hits, and a stunning peak load of seven gigabits per second. During the live streaming of the second Mars Rover landing peak traffic reached almost 50,000 simultaneous online– viewers. NASA too has prudentially turned to the services of a CDN service provider to handle such spikes in traffic.
Touch down on Indian soil and companies like Rediff.com saw the advantage of caching in on a CDN service provider’s network as early as 2001. Rediff.Com was, in fact, able to service the global Indian community, growing more diverse and more dispersed, a combination of an online-offline resource which allows consumers to remain connected for all their communication, community and content needs with their friends and families around the world. The CDN service provider ensured that Rediff could provide all this, hence enabling Rediff to attract and retain customers, and all this while saving them considerable amounts of time and money.
What is CDN?
Webopedia defines a CDN as “A network of servers that delivers a Web page to a user based on the geographic locations of the user, the origin of the Web page and a content delivery server. A CDN copies the pages of a Web site to a network of servers that are dispersed at geographically different locations, caching the contents of the page. When a user requests a Web page that is part of a CDN, the CDN will redirect the request from the originating site’s server to a server in the CDN that is closest to the user and deliver the cached content. The CDN will also communicate with the originating server to deliver any content that has not been previously cached.”
CDNs use infrastructure technologies like caching to push replicated content close to the network edge. Global load balancing ensures that users are transparently routed to the “best” content source. Stored content is kept current and protected against unauthorized modification. Customer-accessible traffic logs enable data mining for marketing and capacity planning.
Most importantly, customers—typically, large enterprise Web site owners—determine the content served by the CDN by selectively reassigning URLs (Uniform Resource Locator or your Web site’s address) to embedded objects. Dynamic or localized content can be served up by the customer’s own site, avoiding the CDN, while static and easily distributed content can be retrieved from the nearest CDN server.
Who Uses a CDN Provider and Why
They are the big and the small, the short and the tall, and everything in between. You can go to any CDN provider’s Web site and see a list of customers or wade through past press releases with customers’ announcements. A diverse slice of organizations worldwide use CDN providers. They could be technology companies, e-Retail, e Marketing, media & entertainment or the government. All of them now realize that the cost and the effort expended on managing the delivery of their Web site can be outsourced easily and effectively. To their advantage they find that outsourcing of their Web sites has ensured that high level of performance at critical times minus the exorbitant costs and headaches and allows them to focus on what they do best, their core business.
As major telecommunication providers like BSNL, Reliance, Bharti & MTNL move forward with their suite of Broadband Internet services, it is obvious that the future of Internet infrastructure engineering in India will move beyond bandwidth and connectivity to rich content delivery in the not so far away future.
There is promise in the air, in the not-so-far away future, for those who wish the Internet would magically bring up a block buster film trailer, a 1960’s song or a never-before-seen view like that of a satellite landing on a distant planet. For media and entertainment companies, gaming and e-commerce sites, corporates and business houses, this simply means that they now bring the force of the Internet with rich video, audio and digital content to the finger tips of their viewers!
Abhay Dubey, Managing Director, Speedera Networks (India)