IBM® WebSphere® Application Server includes the Virtual Member Manager (VMM), which IBM WebSphere Portal uses to access user and group information. VMM provides an interface that enables communication between WebSphere Portal and any repository, whether federated repositories, a stand-alone repository, or your own custom user registry.

The Virtual Member Manager (VMM) is an abstract component within the WebSphere Application Server infrastructure. As the following diagram illustrates, WebSphere Portal uses the Portal User Management Architecture (PUMA) System Programming Interface (SPI) to retrieve and set attributes on user objects. PUMA passes these requests to VMM, which then passes the requests on to a corresponding registry adaptor that connects VMM to the repository.

Illustration of WebSphere Portal interaction with Virtual Member Manager. Refer to the text in this topic for more information on this graphic.

Virtual member manager provides a secure facility to support customer's basic organizational entity management needs. Organizational entities refer to entities that are common to most organizations, such as people, login accounts, business units, security roles, and business roles.

Many products and customer applications have their own components for managing organizational entities. They have different models and repositories of profile information with varying levels of security and functional capabilities. In turn this causes integration problems and the inability to provide a single unified view of the information. Even the terminology differs, from the security domain that deals with users, accounts, security roles, to business applications that need profile information.
Virtual member manager provides a model of the organizational entities that serves the basic needs of a variety of applications, and hides from them the disparate repositories that can be used underneath.
Virtual member manager performs only limited information integration and does not perform any synchronization among multiple repositories. Virtual member manager provides a uniform abstraction layer that can be used to manage and to securely access the information on organizational entities. In some deployments, products such as WebSphere Information Integrator and IBM^® Tivoli^® Directory Integrator that provide advanced synchronization and integration capabilities can be used with virtual member manager.

Virtual member manager is available for all the different editions of the WebSphere Application Server. The virtual member manager user registry provides user registry functions and allows WebSphere security to be enabled using virtual member manager. Virtual member manager can also be used in a WebSphere Application Server environment in combination with other user registry adapters (for example, WebSphere Application Server LDAP, WebSphere Application Server OS, and custom user registry).

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