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Question 7/15

Question 7/15 - Characteristics of optical components and subsystems
(Continuation of part of Question 7/15)
Motivation
The increasing complexity of optical networks has brought about an increasing diversity of active, passive and hybrid or dynamic/adaptive optical components and. These components and devices  find applications in local access networks, metropolitan and long distance networks, and in submarine networks. Functions differ with the application. This Question addresses the high level need for specifications expressed by the system Recommendations and network operators. It serves as an interface to the component level standards generated outside of ITU-T in organizations such as IEC.
The following major Recommendations, in force at the time of approval of this Question, fall under its responsibility: G.661, G.662, G.663, G.665, G.666, G.667, G.671, G.672, L.12, L.31, L.36 and L.37.
Question
What components aspects and desirable characteristics need to be specified to support local access networks, metropolitan and long distance networks, and submarine networks in the OTN?
What enhancements should be made to existing draft or published Recommendations to reflect technological developments and requirements?
Study items to be considered include, but are not limited to:
  • Active devices and sub-systems such as Optical Fibre Amplifiers (OFAs), including parameter definitions and measurement, classification of devices and sub-systems, optical nonlinearities, polarization, dispersion, noise and optical surge.
  • Passive components such as splices and connectors, attenuators and terminators, 1-by-N branching components (such as splitters and combiners), 2-wavelength optical multiplexers and demultiplexers, filters and isolators, optical switches, dispersion compensators, optical multiplexers / demultiplexers.
  • Worst-case transmission parameter values (for all environments and to end-of-life) for passive components in digital applications.
  • Specification of Optical Amplifier (OA) characteristics in multichannel applications including their frequency equalization and dynamic response.
  • Semiconductor Optical Amplifiers (SOA) and their characteristics.
  • Raman optical amplifiers and their characteristics.
  • Single channel optical amplifiers and their characteristics.
  • Optical transfer function of components.
  • Consider the potential implications of the Flexible DWDM Grid in G.694.1 on all Recommendations under the responsibility of Q7/15 and Q16/15.
  • Specification of other optical amplifier sub-systems (e.g. those resulting from integration of optical amplification with optical multiplexing or dispersion compensation).
  • Specification of components for present and future optical networks, such as OAs with transient control, gain-flattened OAs and wideband OAs, optical circulators, optical modulators, electrically controlled optical attenuators, passive and active dispersion compensators including Polarization Mode Dispersion (PMD) compensators, multi-wavelength and/or fine tuning lasers & ext. modulators, high-power lasers for Raman amplification "flat-top", passband filters, small-size switching matrixes, wavelength/frequency transponders or converters, optical repeaters (2R, 3R).
  • Components and subsystems for use in robust optical transmission systems including advanced modulation formats for 40 Gbit/s and above 100 Gbit/s.
  • OFAs, components and subsystems for use in bi-directional transmission systems on a single fibre.
  • OFAs other than Erbium Doped Fibre Amplifiers (EDFAs).
  • Operations, administration, and maintenance (OA&M) aspects of OAs and Optical Network Elements (ONEs) containing OAs.
  • Further quantification of optical nonlinearities.
  • Parameter values for components with respect to statistical values, such as mean and standard deviation, short-term variations with environment, long-term degradation with aging, use of these in system calculations.
  • Components and subsystems for the All Optical Network (AON), e.g. AOWC (All optical wavelength converter), Optical 3R (Optical 3R Regenerator), Optical 2R (Optical 2R Regenerator), tunable components, Optical Amplifiers with transient control).
  • Enhanced dynamic compensation for both, chromatic dispersion and PMD.
  • Specification of fixed Optical Add/Drop Multiplexer (OADM) and re-configurable Optical Add/Drop Multiplexer (ROADM) and OXC (Optical Cross-Connect) devices.
  • New components and subsystems for the metro and the access networks.
  • Components and subsystems for Optical Packet Switching.
  • Safety and reliability aspects of all the above components, including aspects of operation at high optical power levels.
  • Possible extension of the components and subsystems for use in optical networks that are optimized for packet data transport, e.g. IP or ATM over Wavelength Division Multiplexing (WDM), including optical label switching components.
  • Enhancements that can be made to existing draft and published Recommendations to further reduce the power consumption of optical components and subsystems.
Tasks
Specific tasks include, but are not limited to:
  • Revise Recommendations G.661, G.662, G.663, G.665, G.666, G.667, G.671, L12, L31, L36 and L37.
Relationships
Recommendations:
  • G.6xx and G.9xx Series.
  • L Series.
Questions:
  • Q1/15, Q2/15, Q3/15, Q5/15, Q6/15, Q8/15, Q16/15, Q17/15.
Standardization bodies, forums and consortia:
  • ITU-T SG5
  • IEC SC86B on optical passive components
  • IEC SC86C on active components and dynamic components including all types of optical amplifiers
  • IEC TC76 on laser safety and aspects of safe laser operation.
  • IEC TC46 on cables, wires, waveguides, RF connectors, RF and microwave passive components and accessories.