Rec. ITU-T I.353 (03/1993) � REFERENCE EVENTS FOR DEFINING ISDN PERFORMANCE PARAMETERS
FOREWORD
1 Introduction
2 General definitions
3 Performance-significant reference events
    3.1 Recommendation Q.931 (Recommendation I.451)
    3.2 Recommendation Q.921
    3.3 X.25 layer 2 (LAPB)
    3.4 Recommendation Q.764
    3.5 Frame switching
    3.6 Frame relaying
    3.7 B-ISDN ATM layer
    3.8 Unrestricted digital bearer services