Location and Directory Services

Location and Directory services provide specialized support for locating required resources and for mediation between service consumers and service providers.

The World Wide Web, based on the Internet, has created a need for locating information resources, which currently is mainly satisfied through the use of search engines. Advancements in the global Internet, and in heterogeneous distributed systems, demand active mediation through broker services that include automatic and dynamic registration, directory access, directory communication, filtration, and accounting services for access to resources.

• Directory Services provide services for clients to establish where resources are, and by extension how they can be reached.   "Clients" may be humans or computer programs, and "resources" may be a very wide variety of things, such as names, email addresses, security certificates, printers, web pages, etc.
• Special Purpose Naming Services provide services that refer names (ordered strings of printable characters) to objects within a given context (namespaces). Objects are typically hierarchically organized within namespaces. Examples are:
  • File systems
  • Security databases
  • Process queues
• Service Location Services provide access to "Yellow Pages" services in response to queries based on constraints
• Registration Services provide services to register identity, descriptions of the services a resource is providing, and descriptions of the means to access them.
• Filtering Services provide services to select useful information from data using defined criteria
• Accounting Services provide services such as account open, account update, account balance, account detail, account close, account discounts, account bill/usage tally, account payment settlement based on message traffic, and/or connection time, and/or resource utilization, and/or broker specific (e.g., value based)

Copyright © The Open Group, 1999