Cloud Application Architectures

Chapter 1. Cloud Computing

The hallmark of any buzzword is its ability to convey the appearance of meaning without conveying actual meaning. To many people, the term cloud computing has the feel of a buzzword.

It’s used in many discordant contexts, often referencing apparently distinct things. In one conversation, people are talking about Google Gmail; in the next, they are talking about Amazon Elastic Compute Cloud (at least it has “cloud” in its name!).

But cloud computing is not a buzzword any more than the term the Web is. Cloud computing is the evolution of a variety of technologies that have come together to alter an organization’s approach to building out an IT infrastructure. Like the Web a little over a decade ago, there is nothing fundamentally new in any of the technologies that make up cloud computing. Many of the technologies that made up the Web existed for decades when Netscape came along and made them accessible; similarly, most of the technologies that make up cloud computing have been around for ages. It just took Amazon to make them all accessible to the masses.

The purpose of this book is to empower developers of transactional web applications to leverage cloud infrastructure in the deployment of their applications. This book therefore focuses on the cloud as it relates to clouds such as Amazon EC2, more so than Google Gmail. Nevertheless, we should start things off by setting a common framework for the discussion of cloud computing.