1、 International Telecommunication Union ITU-T G.972TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (09/2011) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Digital sections and digital line system Optical fibre submarine cable systems Definition of terms relevant to optical fi
2、bre submarine cable systems Recommendation ITU-T G.972 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS G.100G.199 GENERAL CHARACTERISTICS COMMON TO ALL ANALOGUE CARRIER-TRANSMISSION SYSTEMS G.200G.299 INDIVI
3、DUAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LINES G.300G.399 GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON RADIO-RELAY OR SATELLITE LINKS AND INTERCONNECTION WITH METALLIC LINES G.400G.449 COORDINATION OF RADIOTELEPHONY AND LINE TELEPHONY G.450
4、G.499 TRANSMISSION MEDIA AND OPTICAL SYSTEMS CHARACTERISTICS G.600G.699 DIGITAL TERMINAL EQUIPMENTS G.700G.799 DIGITAL NETWORKS G.800G.899 DIGITAL SECTIONS AND DIGITAL LINE SYSTEM G.900G.999 General G.900G.909 Parameters for optical fibre cable systems G.910G.919 Digital sections at hierarchical bit
5、 rates based on a bit rate of 2048 kbit/s G.920G.929 Digital line transmission systems on cable at non-hierarchical bit rates G.930G.939 Digital line systems provided by FDM transmission bearers G.940G.949 Digital line systems G.950G.959 Digital section and digital transmission systems for customer
6、access to ISDN G.960G.969 Optical fibre submarine cable systems G.970G.979Optical line systems for local and access networks G.980G.989 Access networks G.990G.999 MULTIMEDIA QUALITY OF SERVICE AND PERFORMANCE GENERIC AND USER-RELATED ASPECTS G.1000G.1999 TRANSMISSION MEDIA CHARACTERISTICS G.6000G.69
7、99 DATA OVER TRANSPORT GENERIC ASPECTS G.7000G.7999 PACKET OVER TRANSPORT ASPECTS G.8000G.8999 ACCESS NETWORKS G.9000G.9999 For further details, please refer to the list of ITU-T Recommendations. Rec. ITU-T G.972 (09/2011) i Recommendation ITU-T G.972 Definition of terms relevant to optical fibre su
8、bmarine cable systems Summary Recommendation ITU-T G.972 applies to optical fibre submarine cable systems. The purpose of this Recommendation is to provide definitions of terms relevant to optical fibre submarine cable systems, including terms relevant to system configuration, system aspects, termin
9、al equipment, optical submarine repeaters and branching units, optical fibre submarine cable, manufacturing and installation, and the maintenance of the submarine portion. Appendix I is the alphabetical list of terms defined in this Recommendation. History Edition Recommendation Approval Study Group
10、 1.0 ITU-T G.972 1993-03-12 XV 2.0 ITU-T G.972 1997-04-08 15 3.0 ITU-T G.972 2000-10-06 15 4.0 ITU-T G.972 2004-06-13 15 5.0 ITU-T G.972 2008-03-29 15 6.0 ITU-T G.972 2011-09-06 15 ii Rec. ITU-T G.972 (09/2011) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialize
11、d agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a
12、 view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recomme
13、ndations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conc
14、iseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the Recommend
15、ation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party.
16、 INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Righ
17、ts, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementer
18、s are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2012 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written perm
19、ission of ITU. Rec. ITU-T G.972 (09/2011) iii Table of Contents Page 1 Scope 1 2 References. 1 3 Definitions 2 3.1 Terms relevant to elements of system configuration 2 3.2 Terms relevant to system aspects . 6 3.3 Terms relevant to terminal equipment 8 3.4 Terms relevant to optical submarine repeater
20、s and branching units 10 3.5 Terms relevant to optical fibre submarine cable 10 3.6 Terms relevant to manufacturing and installation 12 3.7 Terms relevant to the maintenance of the submarine portion 13 4 Abbreviations and acronyms 14 Appendix I Alphabetical list of terms defined in this Recommendati
21、on 16 Bibliography. 22 Rec. ITU-T G.972 (09/2011) 1 Recommendation ITU-T G.972 Definition of terms relevant to optical fibre submarine cable systems 1 Scope The purpose of this Recommendation is to provide definitions of terms relevant to optical fibre submarine cable systems. A small number of term
22、s defined in this Recommendation are associated with definitions in ITU-T G.601, ITU-T G.602 and ITU-T G.701. References to these definitions are given in parenthesis as an aid to ensure consistency between the different Recommendations in the event of future amendments. Figure 1 of ITU-T G.971 show
23、s the basic concept of optical fibre submarine cable systems and boundaries. Optical submarine repeaters or optical submarine branching units could be included, depending on each system requirement. In Figure 1 of ITU-T G.971, A denotes the system interfaces at the terminal station (where the system
24、 can be interfaced to terrestrial digital links or to other submarine cable systems) and B denotes beach joints or landing points. Letters in brackets in the definitions of this Recommendation refer to the above figure. 2 References The following ITU-T Recommendations and other references contain pr
25、ovisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to investigate the poss
26、ibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recomm
27、endation. ITU-T G.601 Recommendation ITU-T G.601 (1988), Terminology for cables. ITU-T G.602 Recommendation ITU-T G.602 (1988), Reliability and availability of analogue cable transmission systems and associated equipments. ITU-T G.652 Recommendation ITU-T G.652 (2009), Characteristics of a single-mo
28、de optical fibre and cable. ITU-T G.653 Recommendation ITU-T G.653 (2010), Characteristics of a dispersion-shifted, single-mode optical fibre and cable. ITU-T G.654 Recommendation ITU-T G.654 (2010), Characteristics of a cut-off shifted, single-mode optical fibre and cable. ITU-T G.655 Recommendatio
29、n ITU-T G.655 (2009), Characteristics of a non-zero dispersion-shifted single-mode optical fibre and cable. ITU-T G.656 Recommendation ITU-T G.656 (2010), Characteristics of a fibre and cable with non-zero dispersion for wideband optical transport. ITU-T G.701 Recommendation ITU-T G.701 (1993), Voca
30、bulary of digital transmission and multiplexing, and pulse code modulation (PCM) terms. ITU-T G.870 Recommendation ITU-T G.870/Y.1352 (2010), Terms and definitions for optical transport networks (OTN). 2 Rec. ITU-T G.972 (09/2011) ITU-T G.872 Recommendation ITU-T G.872 (2001), Architecture of optica
31、l transport networks. ITU-T G.957 Recommendation ITU-T G.957 (2006), Optical interfaces for equipments and systems relating to the synchronous digital hierarchy. ITU-T G.971 Recommendation ITU-T G.971 (2010), General features of optical fibre submarine cable systems. ITU-T G.976 Recommendation ITU-T
32、 G.976 (2010), Test methods applicable to optical fibre submarine cable systems. 3 Definitions This Recommendation defines the following terms: 3.1 Terms relevant to elements of system configuration 1001 optical fibre submarine cable system: A set of equipment designed to permit the interconnection
33、of two or more terminal stations. The optical fibre submarine cable system is usually composed of terminal equipment (terminal transmission equipment, power feeding equipment, maintenance controller, etc.), and submersible equipment (cable, repeater(s), branching unit(s), etc.). 1002 optical fibre s
34、ubmarine cable link: A link which interconnects two terminal stations using a single optical fibre submarine cable system or an integrated system using system portions supplied by different suppliers. 1003 optical fibre submarine cable network: A network which interconnects three or more terminal st
35、ations using a single optical fibre submarine cable system or an integrated system made of system portions supplied by different suppliers. 1004 land portion: The portion between the system interface in the terminal station (A), and the beach joint or landing point (B) when it exists. It includes th
36、e optical fibre land cable, land joints and the system terminal equipment. 1005 submarine portion: The portion of the system laying on the seabed, between the beach joints or landing points (B), which includes the optical fibre submarine cable and the submarine equipment (e.g., optical submarine rep
37、eater(s), optical submarine branching unit(s) and optical submarine cable jointing box(es). 1006 beach joint: The cable joint made between the optical fibre submarine cable and the optical fibre land cable. 1007 terminal station: The telecommunication station usually located in the vicinity of the l
38、anding point and housing the optical fibre submarine cable system terminal equipment and that of associated terrestrial systems. 1008 terminal station equipment (TSE): The TSE comprises the STE and the ancillary equipment used for the operation of the optical fibre submarine cable system. 1009 syste
39、m terminal equipment (STE): The STE comprises all equipments specific to a given optical fibre submarine cable system. 1010 terminal transmission equipment (TTE): The equipment terminating the optical submarine transmission line at the optical interface and connected to the system interface. 1011 su
40、pervisory system: The whole of equipment and sub-assemblies commonly providing one or more of the following functions: monitoring the performance of the submarine equipment and sub-assemblies; Rec. ITU-T G.972 (09/2011) 3 monitoring the performance of the system terminal equipment; monitoring the en
41、d-to-end performance of the digital line sections; enabling fault location inside the submarine plant, to within one repeater section, where possible; controlling redundancy switching, if provided inside the submarine portion; providing interfaces to other management facilities. 1012 maintenance con
42、troller: A computer with an interface to the supervision and remote maintenance equipment, which is commonly used during the supervision and remote maintenance activity. 1013 power feeding equipment (PFE): The equipment providing, through a power conductor in the optical fibre submarine cable, a sta
43、bilized constant electrical current for powering optical submarine repeaters and/or optical submarine branching units. 1014 cable terminating equipment (CTE): The equipment providing the interface between the optical fibre from the TTE and the optical fibre cable, and the interface between the power
44、 feeding line from the PFE and the power feeding conductor from the optical fibre cable. NOTE The CTE is usually part of the PFE. 1015 power feed earth: The earth provided to establish the return path of the repeater power feeding current circuit. 1016 power feed earth electrode cable: The cable ins
45、talled between the power feed earth and the PFE. 1017 optical fibre station cable: The optical fibre cable installed inside the cable station. 1018 optical fibre land cable: The optical fibre cable installed between the CTE and the beach joint. 1019 optical fibre submarine cable: The submarine cable
46、 using optical fibres as transmission line. 1020 optical submarine repeater: (Related to definition 1001 provided in ITU-T G.601) An equipment essentially including one or more regenerators or amplifiers and associated devices, in the submarine portion. 1021 bipolar repeater: An optical submarine re
47、peater which can be powered by a power feeding current flowing in either direction. 1022 branching unit (BU): An equipment connecting more than two optical fibre submarine cable sections. NOTE Applications for the optical submarine branching may include the following additional functions: optical si
48、gnal path switching; signal regeneration or amplification; power path switching. 1023 undersea branching multiplexer (UBM): A branching unit that separates lower level digital signals from incoming optical line signals and recombines them differently in outgoing optical line signals. 1024 integratio
49、n specification: A set of specifications established to permit the interconnection of two or more optical fibre submarine cable systems designed by different suppliers. 1025 integration line optical interface: The optical interface between fractions of the submarine cable sections provided by different suppliers. 4 Rec. ITU-T G.972 (09/2011) 1026 shallow water: Water depths down to a given limit, corresponding to the depths of fishing activity, or more generally of marine activity, creati
