Even though the ink is barely dry on the documentation for Active Server Pages 3.0, Microsoft is already hard at work on the next generation of their core server-side programming technology. In this chapter, we introduce this new product, and look at what it is all about. Currently called ASP+ Next Generation Web Services (though this name might yet change) we'll see why we need a new version of ASP, and explore the concepts behind its design and implementation. While this book is aimed predominantly at experienced developers who have used ASP before, we start out in this chapter by examining some of the core issues involved when you decide to migrate to ASP+.

ASP+ is designed to be backwards-compatible with earlier versions of ASP, with only minor changes required in some circumstances (we explore these further in the appendices). However, more to the point, you can install ASP+ on an existing Windows 2000 server alongside ASP 3.0. This allows you to experiment with the new version, without requiring a separate 'test bed' server. You can continue using existing ASP applications, and migrate them ASP+ when you are ready, so your investment in ASP is not lost.

But simply porting your applications to ASP+ will only give you a few of the benefits the new version offers. ASP+ has many new features that provide far greater ease of use, more power and better
runtime efficiency, but to take advantage of them you will need to understand more about the way
that ASP+ works.

As we are writing this book using a preview version of ASP+, we can't be exactly sure of all the features of the final release. But thanks to the information and assistance provided by the ASP+ team at Microsoft, we can be pretty sure that the content of the book will be reliable and useful with the final version. We'll also be maintaining a special Web site that is accessible from http://www.wrox.com/beta, where we'll document changes as the beta and final release versions appear, and provide some detailed information as well.

So, in this first chapter, we'll cover:

• How Active Server Pages has evolved since its inception
• What the new runtime framework is
• How ASP+ is different to ASP, and why
• A brief guide to getting started with ASP+
• Some of the changes expected in the final release version

We start with a look at the way that ASP and ASP+ have evolved, as this will help to set the background for understanding and working with the new product. For more information about working with COM+ and previous versions of ASP, check out Professional ASP 3.0, (ISBN 1-861002-61-0) from Wrox.