Information technology — International Standardized Profiles TB, TC, TD and TE — Connection-mode Tra...
Specifies the requirements for the Data Link Layer that apply specifically to configurations involving access to an ISDN subnetwork. The requirements specified in this part apply to Service Access Point Identifier (SAPI) of value 0 used to provide Data Link Layer services to a call control Layer 3 entity and to SAPI of value 16 used to provide Data Link Layer services to an X.25 Layer 3 entity.