CCITT Rec. I.325 (11/1988) � REFERENCE CONFIGURATIONS FOR ISDN CONNECTION TYPES
1 Summary
2 Introduction
    2.1 Objective
    2.2 Relationship to other I-series Recommendations
3 Development of the concept of reference configurations
    3.1 Definitions
    3.2 Principles for developing reference configurations for ISDN connection types
    3.3 Connection elements
    3.4 Functional groupings
    3.5 Reference points
4 Specific reference configurations
    4.1 64 kbit/s class
    4.2 Packet class
    4.3 Broadband class