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