The H.350-series describes a directory services architecture for
multimedia conferencing and uses LDAP (Lightweight Directory Access
Protocol) to store users’ voice, video and collaborative multimedia
information in a way that integrates with directory and identity
management systems already in place at universities, large enterprises
and service provider networks. Extensions to support X.500 directory
services are also available. H.350 enables providers to scale up video
and VoIP operations from a few hundred endpoints to full enterprise and
carrier level deployments. Account configuration details, authentication
and authorization are linked to the enterprise directory using LDAP.
Currently, the H.350-series comprises the following standards:
ITU-T Recommendation H.350 – Directory services architecture for multimedia conferencing: Describes a directory services architecture for multimedia
conferencing using LDAP. Extensions have been made to also support X.500
directory services. Standardized directory services support association
of individuals with endpoints, searchable directories (a.k.a. white
pages), and clickable dialling. Directory services can also assist in
the configuration of endpoints, and user authentication based on trusted
data sources. H.350 also describes a standardized LDAP schema to
represent endpoints on the network and associate those endpoints with
users. It discusses design and implementation considerations for the
interconnection of video- and voice-specific directories, enterprise
directories, call servers and endpoints.
- ITU-T Recommendation H.350.1 – Directory services architecture for H.323: Describes LDAP and X.500 schemas to represent H.323 endpoints.
- ITU-T Recommendation H.350.2 – Directory services architecture for H.235: Describes LDAP and X.500 schemas to represent H.235 elements.
- ITU-T Recommendation H.350.3 – Directory services architecture for H.320: Describes LDAP and X.500 schemas to represent H.320 endpoints.
- ITU-T Recommendation H.350.4 – Directory services architecture for SIP: Describes LDAP and X.500 schemas to represent SIP user agents.
- ITU-T Recommendation H.350.5 – Directory services architecture for non-standard protocols: Describes LDAP and X.500 schemas to represent non-standard multimedia
communications endpoints, and is meant to provide a very basic
framework for representing these elements in a directory.
- ITU-T Recommendation H.350.6 – Directory Services Architecture for Call Forwarding and Preferences: Describes simple LDAP and X.500 schemas to represent call forwarding
and call preference information in an H.350 directory. It is intended to
represent addresses to which calls should be forwarded in case an
endpoint does not answer a call. It can also represent advanced
functionality, such as directing a caller to a web page or email screen
when the called endpoint is not available.
- ITU-T Recommendation H.350.7 – Directory Services Architecture for XMPP: Describes
LDAP and X.500 schemas to represent XMPP URIs and user information in
the directory so that an organization can directory-enable and manage
XMPP resources in the same way that other multimedia protocols (e.g.
H.320, H.323, SIP) are managed in H.350.
- ITU-T Recommendation H.351 - Semantic Web Interface for Multimedia Terminal and System Directories (SWIM-D):
Describes a semantic web interface in XHTML that can be used to provide
directory lookup and menu capabilities for multimedia terminals and
- H.350-Series Implementer’s Guide: This document contains the latest updates, clarifications and defect
fixes identified (but not yet formally incorporated) for the
Recommendations of the H.350 Series.
NOTE - Currently, there are no implementers guide in force for the H.350 series.