Book excerpt: The web services architecture provides a new way to think about and implement application-to-application integration and interoperability that makes the development platform irrelevant. Two applications, regardless of operating system, programming language, or any other technical implementation detail, communicate using XML messages over open Internet protocols such as HTTP or SMTP. The Simple Open Access Protocol (SOAP) is a specification that details how to encode that information and has become the messaging protocol of choice for Web services.Programming Web Services with SOAP is a detailed guide to using SOAP and other leading web services standards--WSDL (Web Service Description Language), and UDDI (Universal Description, Discovery, and Integration protocol). You'll learn the concepts of the web services architecture and get practical advice on building and deploying web services in the enterprise.This authoritative book decodes the standards, explaining the concepts and implementation in a clear, concise style. You'll also learn about the major toolkits for building and deploying web services. Examples in Java, Perl, C#, and Visual Basic illustrate the principles. Significant applications developed using Java and Perl on the Apache Tomcat web platform address real issues such as security, debugging, and interoperability.Covered topic areas include: The Web Services Architecture SOAP envelopes, headers, and encodings WSDL and UDDI Writing web services with Apache SOAP and Java Writing web services with Perl's SOAP::Lite Peer-to-peer (P2P) web services Enterprise issues such as authentication, security, and identity Up-and-coming standards projects for web services Programming Web Services with SOAP provides you with all the information on the standards, protocols, and toolkits you'll need to integrate information services with SOAP. You'll find a solid core of information that will help you develop individual Web services or discover new ways to integrate core business processes across an enterprise.