February 21, 2001, 10:20 AM — IN THE LAST SEVERAL YEARS, the Internet has evolved from a mechanism for transporting text and simple images to a vehicle for multimedia and other bandwidth-heavy content types that demand higher service levels than the Internet alone can provide.
These factors, coupled with an increased awareness on the part of content providers and e-business leaders that Web site performance plays a crucial role in online success, are driving the CDN (content delivery network) services surge.
CDN services are designed to improve Web site performance by routing content on a specialized overlay network of servers or datacenters that tap a variety of content-speeding technologies, including caching, load balancing, and replication. On top of these infrastructures, CDN providers offer a variety of services ranging from basic routing of static or dynamic content to streaming media and professional services.
This method of outsourcing content delivery has become an attractive option for many business leaders who are trying to sustain performance and reliability of their online presence while controlling the cost of infrastructure build-out. Although the market is now taking off, consumers of CDN services -- including enterprises, Web hosting companies, and ASPs (application service providers) -- are facing a slew of confusing choices.
Because it lacks the means to control quality, the Internet can be a less than desirable medium for transmitting valuable business content and transactions to users. Although providers agree that performance problems exist, they disagree on what causes the problems or how to tackle them, according to Peter Christy, an analyst at Jupiter Research in New York.
For example, some providers believe that congestion is spread more or less equally across the network, whereas others concentrate efforts on the network edge.
This difference in opinion has resulted in varying technical approaches to content delivery. Cambridge, Mass.-based Akamai leverages its worldwide network of about 8,000 distributed servers to push content out to and deliver it from a point closer to the end-users. In contrast, Woburn, Mass.-based Mirror Image Internet follows an aggregated model, with deployment worldwide of 22 high-capacity datacenter structures, or CAPs (content access points). The CAPs are designed to improve performance by reducing the number of hops that content must make across routers.
Not every provider takes a brute-force approach: epicRealm, for instance, touts an ebusiness-friendly approach using a network of servers and datacenters to respond to the fluctuating needs of business content and applications, and San Francisco-based Digital Island combines content delivery services, hosting, and a private fiber-optic network with strategically placed datacenters around the world.
A variety of answers