A little over 30 years ago, the development of TCP/IP provided the technical foundation for the Internet. A scant 10 years ago, HTTP and HTML were developed as foundations for the Web. At the turn of the twenty-first century, XML had heralded new frontiers for e-business, promising robust new layers of middleware. The de facto standardization of XML made this possible, spawning thousands of new niche applications. And just as HTML delivered publishing tools to all who have access to the Web, the XML-based standards and protocols underlying the development of Web services will deliver comparative expansion in service provision. “Web services” will extend the notion of who may become a service provider.

With advances in computer networks and programming — driven by the increasingly collaborative and distributed nature of business, research, and learning — the next generation of the Web is being built to accommodate integrated, dynamic, and transactional processes that assist in supporting peer collaboration and automating workflow. Importantly, Web services standards and protocols are being developed upon the foundations already in place. Moreover, Web services provide a “future-proofed” means for scalable Internet applications and capability.
Key technologies enabling this layer of infrastructure development include:

• XML (eXtensible Markup Language);
• SOAP (Simple Object Access Protocol);
• UDDI (Universal Description, Discovery and Integration); and
• WSDL (Web Services Description Language).

While Web services can be deployed in a variety of both proprietary and non-proprietary ways, the essential capability is platform-neutral. During 2002, the W3C established a number of working groups to develop abstract models and formal definitions of Web services.

The Web Services Description Language (WSDL) has been one of the ongoing outputs of this work and is a means for exposing and discovering services, applications, and data in a standard XML description, thereby enabling dynamic interactions between distributed applications.

What sorts of Web services applications could be developed for learning settings? Gleason (2002) and Jacobson (2002) offer the following examples:

• a class roster services that provides class rosters to online grade books and enterprise-wide learning management systems;
• a clearinghouse function that validates the immigration status of international students;
• a credit card service that accepts credit card and payment information and returns bank authorization;
• an interface service that permits students, faculty, and researchers to use an online art collection on their own terms; and
• a student loan tracking service that allows students to monitor the status of guaranteed student loans.

Over the next five years, Web services-based applications will enable many enterprises to integrate “best of breed applications” into their existing enterprise applications infrastructures.