CONTENTS

 1     Introduction
 2     Parameters related to reliability and availability of fibre optic systems
        2.1     Fibre optic system availability and maintenance reliability-related parameters
        2.2     Active optical device reliability parameters
        2.3     Passive optical device reliability parameters
        2.4     Optical fibre and cable reliability parameters
 3     Definitions
 4     Steady-state reliability prediction method of devices, units and fibre optic systems in serial configuration
        4.1     Purpose and scope
        4.2     Applications of the predicted failure rate method
                  4.2.1     Equipment manufacturers/suppliers
                  4.2.2     Equipment owners and network operators
        4.3     Guidelines
                  4.3.1     Definition of failure
                  4.3.2     Operating conditions
                  4.3.3     Environmental description
                  4.3.4     Adjusting the estimates given by this method
        4.4     Steady-state failure rate prediction method
                  4.4.1     Applicability of the method
                  4.4.2     Device steady-state failure rate (lsi)
                  4.4.3     Unit steady-state failure rate (λs)
                  4.4.4     Line system steady-state failure rate (λsys)
 5     Calculation methodologies for fibre optic system devices, units and systems in serial configuration regarding reliability and maintenance parameters
        5.1     Plug-in circuit pack MTBF
        5.2     System MTBF (terminal and repeater)
        5.3     Frequency of scheduled maintenance actions
        5.4     Random failure rate
        5.5     Infant mortality factor
 6     Calculation methodology of availability and maintenance parameters of fibre optic systems with line protection
        6.1     General considerations – Line protection and network protection
        6.2     State-space methodology to determine availability and maintenance parameters in fibre optic systems with line protection
                  6.2.1     Step 1 – Inputs
                  6.2.2     Step 2 – From the above inputs determine
                  6.2.3     Step 3 – Calculating system reliability-related measures
        6.3     Options of fibre systems with line protection
                  6.3.1     One-for-one (1 + 1) link protection
                  6.3.2     One-for-N (N+1) link protection
                  6.3.3     Rings
 7     Reference circuits for end-to-end channel availability of line systems on optical fibres
 8     Allocation methodology for end-to-end unavailability objectives
        8.1     Contributors to unavailability – Considerations regarding SDH and PDH systems on optical fibres
        8.2     Allocation methodology
Appendix I – Determination of unit steady-state failure rate – Example
        I.1     Unit description (example)
        I.2     Reliability parameters of devices (example)
        I.3     Unit steady-state failure rate (FITs)
Appendix II – Study case channel availability for a 4 ´ 140 Mbit/s repeater link on optical fibres with "3 + 1" line protection
       II.1     Description
       II.2     Results – Unavailability (minutes/year) per 140 Mbit/s channel
Appendix III – Study case – Channel availability for a point-to-point fibre connection in the local network with "1 + 1" line protection, with and without cable-path redundancy
      III.1     Description
                III.1.1     Nature of the problem
                III.1.2     Type of connections
      III.2     Results