Throughout this issue, you'll read all about the promise of Web Services and how the .NET Framework enables Web Service development. Many people will also be building their Web Services atop C++ code and frameworks like ATL Server, particularly when performance is paramount. In this article, the authors show how fully functional Web Services are built using ATL Server and Visual Studio .NET. Beginning with unmanaged C++ classes, they add ATL attributes that make the code work over HTTP. Kirk Fertitta and Chris Sells

Direct Internet Message Encapsulation (DIME) is a new specification for sending and receiving SOAP messages along with additional attachments, like binary files, XML fragments, and even other SOAP messages, using standard transport protocols like HTTP. In this article, the author explains what DIME is and how it differs from MIME encapsulation. A detailed description of the message format and how it is parsed, as well as working with SOAP and extending it with WSDL, is also included. Jeannine Hall Gailey

The Office XP Web Services Toolkit makes it possible to build applications that gather information and trigger transactions through various Web Services. The toolkit allows you to easily discover Web Services remotely. It also includes the Web Service Reference Tool, which lets you call a Web Service from inside an Office application. This article shows how toolkit-generated code can be used to access simple, as well as complex, Web Services.The author steps through the auto-generated code to explain the classes that collect parameters, the schema to format the request/response, and the actual operations of the Web Service. Krishnamurthy Srinivasan

Performance is an important concern for any application, but becomes critical when the app is a Web Service accessed by thousands of clients simultaneously. One hardware approach to distributing Web Services requests evenly is a Web farm consisting of multiple servers. Once on a Web farm, Web Service performance can be improved by using ADO.NET DataSet objects to cache frequently accessed data, reducing round-trips to the database. Here the author describes data caching in a Web farm environment and discusses how to avoid the cross-server synchronization problems inherent in this approach. David Burgett

Web Services are all about exchanging data in the form of XML messages. If you were about to design a database schema, you probably wouldn't let your tool do it for you. You'd hand-tool it yourself to ensure maximum efficiency. In this article, the author maintains that designing a Web Service should be no different. You should know what kind of data will be returned by Web Service requests and use the structure of that data to design the most efficient message format. Here you'll learn how to make that determination and how to build your Web Service around the message structure. Yasser Shohoud

Over the years, many industry-standard XML schemas and dialects have been developed. These industry-specific schemas embrace the original purpose of XML and are extremely valuable in promoting and supporting B2B interaction. Unfortunately, the ASP.NET Web Services runtime does not allow developers to directly reference external schemas from within their XML Web Services interface (the WSDL file). This article builds an external schema framework as an extension to the ASP.NET Web Services runtime to enable you to reference external schemas within your XML Web Service interface. Scott Short

Building Web Services to provide enterprise-level solutions is only the first step. You need to take care of the infrastructure aspects of your solution as well, including provisioning, billing, security, and reporting. In this article, the author uses the .NET Framework and SQL Server 2000 to design a provisioning system that will take care of all these housekeeping tasks. He discusses the general requirements of a Web Service provisioning system, walks through the implementation, and then outlines various scenarios for putting this system to work. Chandu Thota