ITU-T RECOMMENDATION I.121 (1988)
1 Principles and concept
1.1 Principles of B-ISDN
1.2 Evolution of B-ISDN
2 Service aspects of B-ISDN
2.1 General
2.2 Service classes
2.3 Definition of service classes
2.4 Examples of broadband services
2.5 User-network interface from the service point of view
3 Architecture models
3.1 Functional architecture
3.2 Basic architectural model
3.3 Reference configurations
3.4 B-ISDN protocol model for ATM
4 Asynchronous transfer mode characteristics
4.1 General considerations
4.2 Header functions
4.3 Header format
4.4 Header size
4.5 Information field size
5 Broadband channel rates
6 User-network interface (UNI)
6.1 General
6.2 Structure of 150 Mbit/s UNI
6.3 Structure of 600 Mbit/s UNI
6.4 Physical and functional characteristics
7 Network aspects
7.1 Generalities
7.2 Transmission of ATM
7.3 Synchronization
7.4 Signalling
7.5 Traffic management and usage monitoring
8 Adaptation between ATM and non-ATM parts of the ISDN
ANNEX A - Examples of broadband services
ANNEX B - Definitions of possible broadband service families and their attribute values
B.1 broadband unrestricted bearer services
B.2 high quality broadband videotelephony services
B.3 high quality broadband videoconference services
B.4 high definition TV and existing quality TV distribution services
B.5 broadband videotex services