10.2.1 Overview

Recommendation H.350 describes a standardized LDAP schema to represent various endpoints on the network and associate these endpoints with users. This provides an opportunity for endpoints to conveniently store their protocol related information on an LDAP.

H.350 architecture uses a primary functional object class, called commObject, to represent attributes of endpoints common to any video or voice protocol. Auxiliary classes are then used to represent specific protocols, such as SIP and H.323.

The H.350 recommendation allows the extension of an existing enterprise directory (a database, typically in LDAP, maintained by an institution that contains information about people and resources in the institution) to include the commObject information.

There are two basic components in the architecture. The commURI object is a class whose only purpose is to link a person or resource to a commObject. By placing a commURI "pointer" in an individual's directory entry, the individual becomes associated with the particular targeted commObject. Similarly, commObject contains a pointer, called commOwner, which points to the individual or resource that is associated with the commObject. In this way, people or resources can be associated with endpoints. The only change required in the enterprise directory is the addition of the simple object class commURI.

Recommendation H.350.4 describes an LDAP directory services architecture for multimedia conferencing using SIP. In particular, it defines an LDAP schema to represent SIP UAs on the network and associate those endpoints with users. Its attributes include a SIP URI element, Registrar Address, Proxy Address, Address (the IP address or fully qualified domain name of the UA), Password, User Name, and Service Level. These attributes can be downloaded to an endpoint for automatic configuration and published to white pages to enable click-to-call dialing.