Introduction

With the release of the .NET Framework, Microsoft is taking the most significant risk in its history. Microsoft has spent billions of dollars, representing over 80 percent of its R&D budget, on designing and constructing this fundamental shift in its develop-

ment tools in order to build a framework for the future of application development. Microsoft has effectively realized its vision of Windows in every PC and a PC on every desktop. Its current problem is that the desktop represents only a portion of the new Internet universe. With the huge shift brought on by the Internet and its pervasiveness into everything from watches to cell phones to cars, Microsoft must now shift its view of the future from a PC-centric orientation to a service-centric orientation.

So what is the future? From Microsoft’s point of view, the future is delivering software as a service. Instead of purchasing a shrink-wrapped installable solution, you will instead rent, borrow, or purchase application logic across a distributed network. Software will of course still be sold on store shelves. However, most, if not all of the business logic and power of these applications will reside across a set of distributed applications using open Internetbased standards such as XML and HTTP. This framework will open extensive new possibilities for you in the process of designing, constructing, delivering, licensing, and collecting fees for your software.

Why Microsoft .NET?

Why would you as a developer invest in learning and understanding this new foundation of products and services? Those of you who are practicing solution developers already probably have a code base of Windowsand Internet-based applications written in Visual Basic, ASP, C++, or a combination of all three. If you have to address Windows API calls from C++ and Visual Basic and then integrate those calls as a COM component called by an ASP page, you will be amazed at how the .NET Framework–based classes provide a common approach and object model to accessing Windows services and resources. You will be further impressed at how the choice of development languages is no longer dependent upon power, flexibility, or support of OOP best practices. Now all languages compile to a Microsoft Intermediate Language (MSIL) and execute against a Common Language Runtime (CLR).

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Introduction

To those familiar with Java, this will seem very interesting. Because there is an intermediate language, Microsoft needs only to provide support for the CLR on multiple platforms in order to provide full cross-platform portability. While at the time of this writing there were no major announcements in this area, it is anticipated that ports to Linux and other operating systems is a key way Microsoft will be able to recoup its investment. In fact, Microsoft has a migration kit, the Java User Migration Path or JUMP, which contains a set of tools that will enable Java developers to take advantage of the .NET platform. The stated goal of these tools is to provide a path for Visual J++ and other Java developers to preserve their existing Java language projects and migrate those projects to the .NET platform. Once you begin experimenting with C# you will clearly see how realistic it is for this type of approach to affect the Java community.

The Microsoft .NET Architecture

The Microsoft .NET Architecture is split into three essential areas:

The .NET platform, which includes the .NET infrastructure and tools to build and operate a new generation of Web services and applications. The core of the .NET platform is the .NET Framework, which includes C#, VB .NET, ASP.NET, and ADO.NET.

.NET products and services, which include Microsoft Windows, MSN.NET, personal subscription services, Microsoft Office .NET, Microsoft Visual Studio .NET, and Microsoft bCentral for .NET.

Third-party .NET services, which are services created by a vast range of partners and developers who now have the opportunity to produce corporate and vertical services built on the .NET platform.

The .NET platform contains all of the building blocks for creating .NET products and services and integrating third-party .NET solutions. Microsoft is using components of the .NET platform to extend the platform itself and to build additional .NET products. For example, as a developer you will be very impressed or possibly amazed that the entire ASP.NET platform is actually built on C#, which is a new .NET language! Additionally, large portions of the Visual Studio .NET code base are built on a combination of C++, C#, and VB .NET.

One of the most common themes heard throughout the development community concerns the stability of the .NET products and services. Compared with prior shifts in technology, such as when Microsoft moved from a 16-bit architecture to a 32-bit architecture or from DOS to Windows, this round is much more bearable.

.NET servers and applications

Microsoft’s .NET servers can be split into two primary categories: core services platforms and specialized services. The core services platforms form the underpinnings of a traditional Microsoft-centric application, including Windows 2000, SQL Server 2000, and Exchange 2000. These applications are .NET in that they robustly support XML plumbing at the core of their applications and provide the foundation for building distributed applications. The second category of servers provides specialized services. The BizTalk Server 2000, for instance, leverages a higher-level language called XLANG that enables you to define process flows, transaction flows, and contracts. XLANG also allows very deep integration across