Chapter 1. What is Amazon Web Services?
Chapter 1 from Amazon Web Services in Action by Michael Wittig and Andreas Wittig.
- Overview of Amazon Web Services
- The benefits of using Amazon Web Services
- What you can do with Amazon Web Services
- Creating and setting up an AWS account
Amazon Web Services (AWS) is a platform of web services that offers solutions for computing, storing, and networking, at different layers of abstraction. For example, you can use block-level storage (a low level of abstraction) or a highly distributed object storage (a high level of abstraction) to store your data. You can use these services to host websites, run enterprise applications, and mine tremendous amounts of data. Web services are accessible via the internet by using typical web protocols (such as HTTP) and used by machines or by humans through a UI. The most prominent services provided by AWS are EC2, which offers virtual machines, and S3, which offers storage capacity. Services on AWS work well together: you can use them to replicate your existing local network setup, or you can design a new setup from scratch. The pricing model for services is pay-per-use.
As an AWS customer, you can choose among different data centers. AWS data centers are distributed worldwide. For example, you can start a virtual machine in Japan in exactly the same way as you would start one in Ireland. This enables you to serve customers worldwide with a global infrastructure.
Cloud computing, or the cloud, is a metaphor for supply and consumption of IT resources. The IT resources in the cloud aren’t directly visible to the user; there are layers of abstraction in between. The level of abstraction offered by the cloud varies, from offering virtual machines (VMs) to providing software as a service (SaaS) based on complex distributed systems. Resources are available on demand in enormous quantities, and you pay for what you use.
Cloud computing is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (networks, virtual machines, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction.
You can run all sorts of application on AWS by using one or a combination of services. The examples in this section will give you an idea of what you can do.
What’s the most important advantage of using AWS? Cost savings, you might say. But saving money isn’t the only advantage. Let’s look at how else you can benefit from using AWS.
A bill from AWS is similar to an electric bill. Services are billed based on use. You pay for the time a virtual machine was running, the used storage from the object store, or the number of running load balancers. Services are invoiced on a monthly basis. The pricing for each service is publicly available; if you want to calculate the monthly cost of a planned setup, you can use the AWS Simple Monthly Calculator (http://aws.amazon.com/calculator).
AWS is the market leader in cloud computing, offering an extensive product portfolio. Even if AWS has expanded into the enterprise sector during recent years, it is still obvious that AWS started with services to solve internet-scale problems. Overall, AWS is building great services based on innovative, mostly open source, technologies. AWS offers complicated but rock-solid ways to restrict access to your cloud infrastructure.
Microsoft Azure provides Microsoft’s technology stack in the cloud, recently expanding into web-centric and open source technologies as well. It seems like Microsoft is putting a lot of effort into catching up with Amazon’s market share in cloud computing.
You can manage services by sending requests to the API manually via a web-based UI like the Management Console, a command-line interface (CLI), or programmatically via an SDK. Virtual machines have a special feature: you can connect to virtual machines through SSH, for example, and gain administrator access. This means you can install any software you like on a virtual machine. Other services, like the NoSQL database service, offer their features through an API and hide everything that’s going on behind the scenes. Figure 1.10 shows an administrator installing a custom PHP web application on a virtual machine and managing dependent services such as a NoSQL database used by the application.
Users send HTTP requests to a virtual machine. This virtual machine is running a web server along with a custom PHP web application. The web application needs to talk to AWS services in order to answer HTTP requests from users. For example, the application might need to query data from a NoSQL database, store static files, and send email. Communication between the web application and AWS services is handled by the API, as figure 1.11 shows.
When you interact with AWS to configure or use services, you make calls to the API. The API is the entry point to AWS, as figure 1.12 demonstrates.
Next, we’ll give you an overview of the tools available for communicating with API: the Management Console, the command-line interface, the SDKs, and infrastructure blueprints. We will compare the different tools, and you will learn how to use all of them while working your way through the book.
Before you can start using AWS, you need to create an account. Your account is a basket for all your cloud resources. You can attach multiple users to an account if multiple humans need access to it; by default, your account will have one root user. To create an account, you need the following:
It is possible to use your existing AWS account while working through this book. In this case, your usage might not be covered by the Free Tier. So you might have to pay for the use.
At first, the pay-per-use pricing model of AWS might feel unfamiliar to you, as it is not 100% foreseeable what your bill will look like at the end of the month. Most of the examples in this book are covered by the Free Tier, so AWS won’t charge you anything. Exceptions are clearly marked. To provide you with the peace of mind needed to learn about AWS in a comfortable environment, you will create a billing alarm next. The billing alarm will notify you via email if your monthly AWS bill exceeds $5 USD so that you can react quickly.
First, you need to enable billing alarms within your AWS account. The step are illustrated in figure 1.28. The first step, of course, is to open the AWS Management Console at https://console.aws.amazon.com.