CONTENTS

 1     Scope
 2     References
 3     Abbreviations
 4     Interface at 64 kbit/s (E0)
        4.1     Functional requirements
                  4.1.1     Three types of envisaged interfaces
        4.2     Electrical characteristics
                  4.2.1     Electrical characteristics of 64 kbit/s codirectional interface
                  4.2.2     Electrical characteristics of the 64 kbit/s centralized clock interface
                  4.2.3     Electrical characteristics of 64 kbit/s contradirectional interface
 5     Interface at 1544 kbit/s (E11)
        5.1     General characteristics
        5.2     Pulse specification
        5.3     Eye diagrams
 6     Interface at 6312 kbit/s (E21)
 7     Interface at 32 064 kbit/s
 8     Interface at 44 736 kbit/s (E32)
 9     Interface at 2048 kbit/s (E12)
        9.1     General characteristics
        9.2     Specifications at the output ports
        9.3     Specifications at the input ports
        9.4     Grounding of outer conductor or screen
10     Interface at 8448 kbit/s (E22)
       10.1     General characteristics
       10.2     Specification at the output ports
       10.3     Specifications at the input ports
       10.4     Grounding of outer conductor
11     Interface at 34 368 kbit/s (E31)
       11.1     General characteristics
       11.2     Specification at the output ports
       11.3     Specifications at the input ports
       11.4     Grounding of outer conductor
12     Interface at 139 264 kbit/s (E4)
       12.1     General characteristics
       12.2     Specifications at the output ports
       12.3     Specifications at the input ports
       12.4     Grounding of outer conductor
13     2048 kHz synchronization interface (T12)
       13.1     General characteristics
       13.2     Specifications at the output ports
       13.3     Specifications at the input ports
       13.4     Grounding of outer conductor or screen
14     Interface at 97 728 kbit/s
15     Interface at 155 520 kbit/s – STM-1 interface (ES1)
       15.1     General characteristics
       15.2     Specifications at the output ports
       15.3     Specifications at the input ports
       15.4     Specifications at the cross-connect points
       15.5     Grounding of outer conductor
16     Interface at 51 840 kbit/s (STM-0 interface)
       16.1     General characteristics
       16.2     Specifications at the output ports
       16.3     Specifications at the input ports
       16.4     Specifications at the cross-connect points
       16.5     Grounding of outer conductor
Annex A – Definition of codes
        A.1     Definition of B3ZS (also designated HDB2) and HDB3
        A.2     Definition of B6ZS and B8ZS
        A.3     Definition of CMI
Appendix I – 1544 kbit/s specification in the 1991 version of this Recommendation
        I.1        General
        I.2        Interface specification
        I.3        Pulse mask
Appendix II – 64 and 6312 kHz synchronization interface specification for use in Japan
       II.1     64 kHz synchronization interface
       II.2     6312 kHz synchronization interface
Appendix III – 3152 kbit/s interface specification for use in North America