The Amazon Elastic Compute Cloud (EC2) is an infrastructure as a service (IaaS) cloud. This means that it provides computing power and resources that you can use for a fee. You take care of running the software; Amazon EC2 provides the hardware.
To understand Amazon EC2, it’s important to understand the concept of virtualization. When you use your computer at home, it’s very likely that you have one physical “box” sitting on or below your desk, with a power button, disk drives, a video card, and so on. The relationship between the physical machine and the machine you log into is 1 to 1. Virtualization, however, is the idea of hosting multiple “virtual machines” on a single physical box. These virtual machines share some hardware resources, but they appear to the end user as distinct machines that can be logged into and administered separately.
You may have used virtual machines at your place of employment; many companies are using them in the workplace because they are more flexible and cost efficient. Most often, an IT administrator will purchase or choose a powerful machine and configure it to be a “virtual server”, which is a physical machine that hosts multiple virtual machines. Obviously, it takes a powerful computer to act as a virtual server, and it takes a fair amount of IT administration skill to set one up.
Enter Amazon EC2. When you work with Amazon EC2, you create and run virtual machines in Amazon’s data centers. You don’t have to know too much about the details of the virtual servers (nor does Amazon want to reveal this). The idea is that you can focus on the software on your server and let Amazon take care of the hardware needs.
Of course, there is a cost for using these resources. You are charged hourly fees for the computing power used, and for the amount of data that you store on Amazon EC2. Most of the things you can do or use on Amazon EC2 have some sort of fee associated with them, but unless you are running a high-traffic site with many gigabytes of data, computing power and disk space are the two biggest cost concerns.
The benefits of Amazon EC2 can be enormous in some situations. Here are a few of the immediate advantages:
Before going forward, there are two important vocabulary terms that you should understand regarding Amazon EC2:
Esri has created an AMI that has ArcGIS Server installed and configured. You will use these AMIs to create EC2 instances, thereby getting the server software running on Amazon EC2. Once you get the instance running, you can log into it using an application called Windows Remote Desktop. This is the same way that you would remotely log in to any other computer in your network, except this time the machine is outside your network, running on Amazon EC2.
You can perform all of these steps on your own home computer as long as it has an Internet connection. In fact, it's recommended that you use your home computer because some workplace IT departments have placed restrictions on accessing computers outside the firewall (like Amazon EC2 instances) using Remote Desktop. Please note that you cannot use a personal hotspot through a mobile phone to log in to your EC2 instances.