A little over a year ago, I wanted to facilitate free video downloads from my site without incurring excessive hosting costs. I decided to use Amazon's Simple Storage Services (S3). Overall, the experience has been a resounding success. In this article, I'll discuss some of the pros and cons of using S3 to augment ASP.NET websites.
Amazon S3 at a Glance
As paraphrased from Amazon's site, S3 is an Internet storage engine designed to make web scalability easier for developers. Through a set of simple APIs, developers can upload, manage, and control access to data stored on Amazon's servers. It's a highly scalable, reliable, fast, and inexpensive storage infrastructure. S3 helps to commoditize bandwidth and level the playing field for small businessesby allowing companies to scale up content delivery without incurring expensive hosting overhead.
S3 lets users store an unlimited number of objects, each of which can up to 5GB. Rather than monthly fees, users pay for what they consume. In the U.S., Amazon charges monthly for total data uploaded ($.10 per GB), stored ($.15 per GB), and served ($.17 per GB). There are also fees for API calls and requests ($.01 per 10,000 calls/requests). Discounts apply for users serving, storing, or uploading more than 40-50 TB per month.
Amazon has storage servers based in the U.S. and in Europe, where pricing is slightly higher. Amazon can also deliver content stored on S3 servers through their edge servers, which have additional locations such as Japan and Hong Kong. This edge delivery is done through integration with Amazon CloudFront, the company's Content Delivery Network (CDN). To use Amazon's edge servers, you just specify which content to serve and from where and pay an additional 12 to 50 percent in per GB costs for this service, depending on the hosting location.
Interacting with Amazon S3
Objects or resources on S3 servers are stored in user-defined buckets, where each resource is stored with a unique key. Unlike traditional storage, where folders partition the content, Amazon's approach let the service behave like a giant List<key, resource> in the sky, where each resource is a file or other collection of zeros and ones. However, because the folder metaphor is so common in storage, S3 keys containing slashes in the name can be used by developers and third party applications to transparently mimic folder semantics as needed.
Service developers can use SOAP or REST-style HTTP interfaces to create, modify, upload, manage, and list buckets and their contents. More importantly, they can also request files using HTTP GET, meaning that requests against either of the following URIs (Figure 1) would work as HTTP GET requests.
Figure 1