It's been a long time since Amazon.com was just about selling books. Oh, they still sell books and most any other retail item you'd want. But Amazon is also a network computing company. Somewhere along the line it occurred to Amazon management that the gigantic computing and network infrastructure they built to power their online shopping empire is exactly what other businesses wanted, if only they could afford it.
Now they can, thanks to Amazon Web Services (AWS). Amazon is offering its $15 billion global computing infrastructure to small, medium and large companies as a suite of cloud computing resources. These include the Amazon Elastic Compute Cloud (Amazon EC2), Amazon Simple Storage Service (Amazon S3), Amazon SimpleDB for database inquiries, Amazon Simple Queue Service (Amazon SQS) for storing messages as they travel between computers, and now Amazon CloudFront for content delivery.
What makes Amazon a good candidate for delivering content is its worldwide network with worldwide edge locations. Think of these as analogous to POPs or Points of Presence for carriers. Essentially, Amazon has network resources and connections from its private network to the Internet in the United States, Europe, Hong Kong, and Japan. There are 8 locations scattered across the US, 4 in Europe and one each in Hong Kong and Japan. When a user requests something from your Website, Amazon serves up the content from the location that makes the most sense at time. That's usually the one closest to the user.
This is how all content delivery networks work. In essence, they bypass most of the Internet by creating their own private network for the content they are serving. Those networks also usually cache instances of the objects at multiple locations so that one central server doesn't get overwhelmed and network bandwidth doesn't have to be unlimited. The cache servers connect to the Internet at their remote locations and feed a limited number of users.
Content Delivery Networks (CDNs) are likely to expand as the demand for video and other high bandwidth services strain the Internet's backbone to the point of snapping. Internet service providers (ISPs) are also contracting with CDNs to take some pressure off their congested networks, as network neutrality forces keep them from implementing classes of service or just cutting off certain bitstreams.
Amazon's CloudFront is designed to be simple to use and priced by use rather than a flat fee. You use it by storing your objects in an Amazon S3 storage bucket. You'll get a CloudFront URL unique to your content from the CreateDistribution API. That's the address you advertise on your Website. CloudFront will take care of figuring out how to most efficiently deliver your content.
What kind of capacity can CloudFront handle? The defaults are 1,000 Mbps bandwidth for data transfer with a peak rate of 1,000 requests per second. You can request higher limits if you need them.
Amazon CloudFront is targeted at companies that distribute software, have lots of traffic to their websites, or deliver rich media files such as audio and video content.
Should you go with a content delivery network or run your own server farm? You can get prices for CloudFront and other services from Amazon Web Services (AWS). Compare these with what you'll pay to run your own content servers and for bandwidth to your IT center or colocation facility.