Simple storage

Applications that need more than 160GB of storage should use Amazon's Simple Storage Service (S3). With S3, data is stored redundantly on multiple computers at multiple data centers around the world. Information can be stored with HTTP "PUT" commands and downloaded with HTTP "GET". The cost to store data is 15 cents per gigabyte per month, with an added bandwidth cost of 20 cents for every gigabyte of data that's uploaded or downloaded. Fortunately, there is no cost to move data between EC2 and S3. According to Amazon, you can store an "unlimited" amount of information with S3, which basically means that Amazon can buy disks faster than your organization can fill them.

Lately I've been doing a lot of research in computer forensics. My database is roughly 1,000GB in size, and my last experiment took four weeks of computer time to execute on a single computer. With Amazon's Web Services I can store my data in multiple data centers for just US$150 a month. Instead of spending four weeks to run an experiment, I can instantiate 28 virtual machines and run the experiment in a day for $67.20. Or I can instantiate 168 machines and run the experiment in four hours for that same $67.20.

But before you turn your business over to Amazon, there are a lot of questions that you need to consider. Are EC2 and S3 just toys, or are they reliable enough for production systems? What is the chance that an EC2 virtual machine will be taken over or shut down by a hacker? How secure is the information stored in S3 -- who can access it, and who can change it? And what is Amazon's commitment to these services? Most of these questions, it turns out, have something to do with security.

I've been working with EC2 and S3 daily and think that the service is reliable enough for me to start on the process of moving much of my research from computers that I own to virtual machines that I'm renting from Amazon on an as-needed basis. But I don't think that EC2 and S3 are yet providing what's required to service corporate customers.

To use EC2 you create a disk image of a Linux server. This image is digitally signed, encrypted, split into pieces and stored in S3 using tools that Amazon provides. You can instantiate a virtual machine with a remote procedure call to the Amazon Web Services (AWS). Ten minutes later the machine is running; another remote procedure call will give you its IP address.