This Recommendation/International Standard specifies the way in which the underlying service assumed by the protocol defined by ITU-T Rec. X.233 / ISO/IEC 8473-1 is provided by a subnetwork that provides the OSI Data Link service defined by CCITT Rec. X.212 / ISO/IEC 8886, through the operation of a Subnetwork Dependent Convergence Function (SNDCF) as described in ISO/IEC 8648.
This Recommendation/International Standard also provides the PICS proforma for this protocol, in compliance with the relevant requirements, and in accordance with the relevant guidance, given in CCITT Rec. X.290 / ISO/IEC 9646-1.