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DEFINITION: Directory Services Markup Language (DSML) is a proposed standard for using XML to define the data content and structure of a directory and maintain it on distributed directories.

DSML gives developers a simple and convenient way to implement XML-based applications on the Internet. Such support is crucial to e-commerce applications.Directory services provide the best way of naming, describing and finding information and resources in a system while managing the relationship between those resources.

Directories (QuickStudy) typically store and manage information - including names, addresses, phone numbers and access rights - about each user in an enterprise. In addition, directory software also stores and manages access to detailed information about a company's information technology assets, including people, business processes and resources for internal use.

The Internet is built on a foundation of distributed directories, most of which maintain similar information using similar directory applications. That foundation is quite old in Internet time. Early protocols, such as X.500, are still used for aspects of directory management. Also, the distributed structure defined early on is still in place: Directory services are distributed across a network, with each distributed service maintaining a portion of the global database. To the user, the entire directory of network resources is accessible from the local server.

New Technology Needed

But the pending demands of business-to-business e-commerce will likely max out these older technologies. For example, developers and vendors will be hard-pressed to write applications and utilities that can meet the data-handling requirements of the automotive spare parts industry, which is expected to generate millions of daily Internet transactions when it's up and running.

Luckily, the numerous business-to-business exchanges announced this year are still a long way from going live, and vendors are making headway in standardizing directory services. One effort, Directory Services Markup Language (DSML), builds on the predicted dominance of the content-tagging language XML to provide support in e-commerce applications. On the Internet, DSML should make directory information available to a world where information in distributed directories is maintained in different schemas.

DSML was created by an industry group spearheaded by Bowstreet Software Inc., a start-up in Portsmouth, N.H. Last year, Bowstreet convinced IBM, Oracle Corp., the Sun/ Netscape Alliance and Novell Inc. that such a standard was needed. Last July, the group announced its intent to develop it, and on Dec. 7, it turned over the DSML 1.0 specification draft to the Organization for the Advancement of Structured Information Standards, a nonprofit consortium for XML e-commerce standardization.

Establishing Standards

The idea behind the DSML standard is that business-to-business exchange applications can make use of the scalability, replication, security and management strengths of Web directory services without having to re-engineer either the Internet's infrastructure or existing software.

DSML specifies standardized ways for defining directory schemas, including specific XML tags and other metadata information, that are similar to the document type definitions in the Internet programming language HTML, which are managed as directory entries.

XML applications request both data and schema information from directories and consolidate them into one document. Network managers can enable DSML on current directories by simply installing extensions. Lightweight Directory Access Protocol and current vendor application programming interfaces remain in use. Directories continue to work as in the past, except that DSML will enhance business-to-business e-commerce.

Although XML itself is still under development, vendors are now supporting it in products and embracing it wholeheartedly as the e-commerce language that will make business-to-business viable.

A combination of XML and DSML will be essential to Internet directory services, enabling a new generation of applications that use directories more effectively. In particular, DSML will be important to supply-chain and customer service applications, all of which rely heavily on customized presentation of data. DSML metadata descriptions will be the tools for that job.

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