1、INTERNATIONAL TELECOMMUNICATION UNION lTU=T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU G.982 (1 1 /96) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Digital transmission systems - Digital sections and digital line system - Optical line systems for local and access netwo
2、rks Optical access networks to support services up to the ISDN primary rate or equivalent bit rates ITU-T Recommendation G.982 (Previously CCITT Recommendation) STD-ITU-T RECMN G.782-ENGL L77b 48b257L Ob37L24 8T7 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETW
3、ORKS INTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS INTERNATIONAL ANALOGUE CARRIER SYSTEM TRANSMISSION SYSTEMS INDIVIDUAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LINES GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE WITH METALLIC LINES COORDINATION OF RADI
4、OTELEPHONY AND LINE TELEPHONY TRANSMISSION MEDIA CHARACTERISTICS DIGITAL TRANSMISSION SYSTEMS TERMINAL EQUIPMENTS GENERAL CHARACTERISTICS COMMON TO ALL ANALOGUE CARRIER- SYSTEMS ON RADIO-RELAY OR SATELLITE LINKS AND INTERCONNECTION General Coding of analogue signals by pulse code modulation Coding o
5、f analogue signals by methods other than PCM Principal characteristics of primary multiplex equipment Principal characteristics of second order multiplex equipment Principal characteristics of higher order multiplex equipment Principal characteristics of transcoder and digital multiplication equipme
6、nt Operations, administration and maintenance features of transmission equipment Principal characteristics of multiplexing equipment for the synchronous digital hierarchy Other terminal equipment General aspects Design objectives for digital networks Quality and availability targets Network capabili
7、ties and functions SDH network characteristics General Parameters for optical fibre cable systems Digital sections at hierarchical bit rates based on a bit rate of 2048 kbis Digital line transmission systems on cable at non-hierarchical bit rates Digital line systems provided by FDM transmission bea
8、rers Digital line systems Digital section and digital transmission systems for customer access to ISDN Optical fibre submarine cable systems DIGITAL NETWORKS DIGITAL SECTIONS AND DIGITAL LINE SYSTEM Optical line systems for local and access networks G. 1 00-G. 199 G.200-G.299 G.300-G.399 G.400-G.449
9、 G.450-G.499 G.700-G.799 G. 700-G.709 G.710-G.719 G.720-G.729 G.730-G.739 G. 740-G.749 G.750-G.759 G.760-G.769 G.770-G.779 G.780-G.789 G.790-G.799 G.80-G.899 G.800-G.809 G. 8 1 O-G. 8 1 9 G. 820-G. 829 G.830-G.839 G.840-G.899 G .900-G. 999 G.900-G.909 G.91O-G.919 G ,920-G. 929 G .930-G. 939 G. 940-4
10、.949 G.950-G.959 G. 9604.969 G.970-G.979 For further details, please refer to ITU-T List of Recommendations. ITU-T RECOMMENDATION G.982 OPTICAL ACCESS NETWORKS TO SUPPORT SERVICES UP TO THE ISDN PRIMARY RATE OR EQUIVALENT BIT RATES Summary This Recommendation deals with the characteristics of an Opt
11、ical Access Network (OAN) with the capability of transporting interactive services over the Optical Distribution Network (ODN) based on point-to-multipoint configuration using passive optical branching components. The Recommendation considers an OAN for both business and residential customer service
12、 requirements based on 64 kbit/s bearer capabilities up to and including ISDN primary rate services. Source ITU-T Recommendation G.982 was prepared by ITU-T Study Group 15 (1993-1996) and was approved under the WTSC Resolution No. 1 procedure on the 8th of November 1996. FOREWORD ITU (International
13、Telecommunication Union) is the United Nations Specialized Agency in the field of telecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of the ITU. The ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations
14、on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Conference (WTSC), which meets every four years, establishes the topics for study by the ITU-T Study Groups which, in their turn, produce Recommendations on these topics. The app
15、roval of Recommendations by the Members of the ITU-T is covered by the procedure laid down in WTSC Resolution No. 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with IS0 and IEC. NOTE In this Recommendation,
16、the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. INTELLECTUAL PROPERTY RIGHTS The ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a c
17、laimed Intellectual Property Right. The ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, th
18、e ITU hadhad not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementors are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database. O ITU 1
19、997 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the ITU. II Recommendation 6.982 (11/96) CONTENTS Page Scope 1 1 1 2 References 2 3 Abbre
20、viations . 3 4 Definitions Configuration of an OAN . Reference configuration . Functional architecture . 5 5.1 5.2 5 6 Fibre type Transmission methodology Wavelength allocation Wavelength range for the 13 1 O nm region . Wavelength range for the 1550 nm region . 7 8 8.1 8.2 9 9.1 9.2 9.3 6 6 7 7 8 8
21、 9 9 9 10 10 10 OAN system specification OAN capacity and ONU classes . Logical reach limitation ONU functional specification . 9.3.1 ONU core shell. . 9.3.2 ONU service shell . 9.3.3 ONU common shell. OLT functional specification 9.4.1 OLT core shell. 9.4.2 OLT service shell 9.4.3 OLT common shell
22、Operation, Administration and Maintenance (OAM) functionality . UNI and SNI interfaces . 9.4 9.5 11 10 11 11.1 11.2 11 11 11 13 15 15 16 ODN functional requirements Passive optical elements . ODN model 1 1.2.1 ODN model loss calculations 1 1.2.2 ODN model loss calculation technique . Classes for opt
23、ical path loss . Reflectance in ODNs 11.3 11.4 Recommendation G.982 (1 1/96) . 111 . STD-ITU-T RECMN G.782-ENGL L77b 48bZ.571 Ob37328 442 1 1.5 Chromatic dispersion 12 Maximum signal transfer delay 13 Environmental conditions . 14 Safety 14.1 14.2 Appendix I - Optical amplifiers (OAs) for OANs . Ele
24、ctrical safety and protection Optical safety and protection Appendix II - Survey of possible wavelength allocation for interactive services . Appendix III . OAM functionality III . 1 Configuration management 111.2 Performance management 111.3 Fault management 111.4 Security management . Appendix IV
25、- Optical loss calculation techniques . Gaussian statistical approach Monte Carlo statistical approach IV . 1 IV.2 Page 16 16 16 16 16 16 17 18 18 18 19 19 20 20 20 21 iv Recommendation G.982 (11196) STD-ITU-T RECMN G.982-ENGL 199b D q8b2591 Ob37129 389 Recommendation G.982 OPTICAL ACCESS NETWORKS T
26、O SUPPORT SERVICES UP TO THE ISDN PRIMARY RATE OR EQUIVALENT BIT RATES (Geneva, 1996) 1 Scope This Recommendation is intended to describe flexible access networks using optical fibre technology. The intention is to provide for the services of today and also the basis for the future service requireme
27、nts. This Recommendation describes the characteristics of an Optical Access Network (OAN) with the capability of transporting interactive services based on 64 kbit/s bearer capabilities between the user- network interface and the network-network interface. The Recommendation considers an OAN for bot
28、h business and residential customer service requirements up to and including ISDN primary rate services carried over a passive split optical network. Distributive services (e.g. cable TV) are not considered in this Recommendation. The OAN described in this Recommendation should enable the network op
29、erator to provide a flexible upgrade to meet future customer requirements, in particular in the area of the Optical Distribution Network (ODN). The ODN considered is based on the point-to-multipoint tree and branch option. This Recommendation is based on the Time Division Multiple Access (TDMA) prot
30、ocol; however, other protocols are not precluded. Systems using both one and two fibres are described. Although examples are quoted, it is not the intention of this Recommendation to preclude further innovation. The use of optical amplifiers is not excluded within the scope of this Recommendation. 2
31、 References The following ITU-T Recommendations and other references contain provisions 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;
32、 all users of this Recommendation are therefore encouraged to investigate the possibility 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. i 2 3 4 5 J ITU-T Recommendation G.652 (
33、1993), Characteristics of a single-m-ode opticalfibre cable. ITU-T Recommendation G.803 (1 993), Architecture of transport networks based on the Synchronous Digital Hierarchy (SDH) . ITU-T Recommendation G.902 (1 995), Framework Recommendation on functional access networks - Architecture and functio
34、ns, access types, management and service node aspects. ITU-T Recommendation G.955 (1996), Digital line systems based on the 1544 kbith and the 2048 kbith hierarchy on optical fibre cables. ITU-T Recommendation G.957 (1 995), Optical interfaces for equipments and systems relating to the synchronous d
35、igital hierarchy. Recommendation G.982 (11/96) 1 ITU-T Recommendation G.964 (1 994), Y-interfaces at the digital Local Exchange (LE) - V5.1 -interface (based on 2048 kbth) for the support of Access Network (AN). ITU-T Recommendation G.67 1 (1 996), Transmission characteristics of passive optical com
36、ponents. ITU-T Recommendation M.30 1 O (1 996), Principles for a telecommunication management network. ITU-T Recommendation G.653 (1 997), Characteristics of a dispersion-shifted single-mode opticalpbre cable. ITU-T Recommendation G.662 (1 999, Generic characteristics of optical Jibre amplijer devic
37、es and sub-systems. Abbreviations This Recommendation uses the following abbreviations: AF AU FTTB FTTC FTTH FTTO ISDN MCS OA OAM OAN ODN OLT ONU os OTDR SCM SCMA SDH SDM SNI SPF TCM TDMA Adaptation Function Adaptation Unit Fibre-To-The-Building Fibre-To-The-Curb Fibre-To-The-Home Fibre-To-The-Offic
38、e Integrated Services Digital Network Monte Carlo Simulation Optical Amplifier Operation, Administration and Maintenance Optical Access Network Optical Distribution Network Optical Line Terminal Optical Network Unit Operation System Optical Time Domain Reflectometer Sub-carrier Multiplexing Sub-carr
39、ier Multiple Access Synchronous Digital Hierarchy Space Division Multiplexing Service Node Interface Service Port Function Time Compression Multiplexing Time Division Multiple Access 2 Recommendation 6.982 (11/96) TU Tributary Unit UNI User Network Interface UPF User Port Function WDM Wavelength Div
40、ision Multiplexing 4 Definitions This Recommendation defines the following terms: 4.1 passive optical access link: The whole of transmission means between a given network interface (V) and a single user interface (T). The concept of passive optical access link is used in order to allow a functional
41、and procedural description and a definition of the network requirements. The user side and the network side of the access link are not identical and, therefore, the access link is not symmetrical. 4.2 adaptation unit (AU): An AU provides adaptation functions between the Optical Network Unit (ONU) an
42、d the user side. 4.3 diplex working: Bidirectional communication using a different wavelength for each direction of transmission over a single fibre. 4.4 duplex working: Bidirectional communication using the same wavelength for both directions of transmission over a single fibre. 4.5 differential fi
43、bre distance: The difference of distance between the nearest and furthest ONU from the OLT. 4.6 logical reach: The logical reach is defined as the maximum length that can be achieved for a particular transmission system independent of optical budget. 4.7 mean signal transfer delay: The average upstr
44、eam and downstream values between reference points “V“ and “T“: a given value is determined by measuring round-trip delay, then dividing by 2. 4.8 OAN: The set of access links sharing the same network-side interfaces and supported by optical access transmission systems. The OAN may include a number
45、of ODNs connected to the same OLT. 4.9 ODN: An ODN provides the optical transmission means fi-om the OLT towards the users, and vice versa. It utilizes passive optical components. 4.10 OLT: An OLT provides the network-side interface of the OAN, and is connected to one or more ODNs. 4.11 ONU: An ONU
46、provides (directly or remotely) the user-side interface of the OAN, and is connected to the ODN. 4.12 service port function: The Service Port Function (SPF) adapts the requirements defined for a specific SNI to the common bearers handling and selects the relevant information for treatment in the AN
47、system management function. 4.13 space division multiplexing: Bidirectional multiplexing using different fibres for upstream and downstream signals. 4.14 sub-carrier multiplexing: Multiplexing multiple electrical frequencies onto a single fibre at a single wavelength to provide an individual frequen
48、cy to each multipoint-to-point path. Recommendation 6.982 (11/96) 3 STD-ITU-T RECMN G.982-ENGL 199b B 48b2591 Ob37132 973 B 4.15 sub-carrier multiple access: Transmission technique involving the multiplexing of many frequencies onto the same carrier payload. 4.16 simplex working: Communication which
49、 uses a different fibre for each direction of transmission. 4.17 time compression multiplexing: Bidirectional multiplexing using different time slots for upstream and downstream signals. 4.18 time division multiplexing: Multiplexing information onto fixed time ranges. 4.19 time division multiple access: Transmission technique involving the multiplexing of many time slots onto the same time payload. 4.20 wavelength division multiplexing: Bidirectional multiplexing using different optical wavelength for upstream and downstream signals. 4.21 tributary unit: Con
