ITU-T I.321 PDF

General

Recommendation I.320 contains the description of the ISDN protocol reference model (PRM). This Recommendation is based on the ISDN protocol reference model as defined in Recommendation I.320, and wherever not explicitly indicated, it should conform with Recommendation I.320. The purpose of this Recommendation is to take into account the functionalities of B-ISDN, which may eventually be incorporated into Recommendation I.320, as an expansion of the existing ISDN protocol reference model. The Protocol Reference Model in this Recommendation is called "B-ISDN PRM" (protocol reference model of the broadband aspects of ISDN). By applying this B-ISDN PRM, § 4 describes functions associated with individual layers of B-ISDN.