This Recommendation defines a multipoint data delivery service for use in the audiographics and audiovisual conferencing service. It provides the mechanism for multipoint aware applications to send data to all or a subset of the group with a single send primitive and to force, if desired, a uniformly sequenced reception of data at all users. It also provides a token mechanism to allow applications to control scarce resources or do multi-application signalling and synchronization. These services are provided in a manner that is independent of the underlying network connections. The following changes have been incorporated into this Recommendation: - Support for unreliable data transfer was added. - Under certain conditions, MCS protocol version is allowed to differ between providers within a domain. - The MCS-DOMAIN-PARAMETERS service primitive was added. - Parameters were added to MCS-SEND-DATA and MCS-UNIFORM-SEND-DATA service primitives to facilitate data reassembly by the user application. - Minor changes have been made to the Recommendation format.