1、 INTERNATIONAL TELECOMMUNICATION UNION ITU-T L.52TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (05/2003) SERIES L: CONSTRUCTION, INSTALLATION AND PROTECTION OF CABLES AND OTHER ELEMENTS OF OUTSIDE PLANT Deployment of Passive Optical Networks (PON) ITU-T Recommendation L.52 ITU-T Rec. L.52 (05/2003
2、) i ITU-T Recommendation L.52 Deployment of Passive Optical Networks (PON) Summary This Recommendation describes the deployment of passive optical networks (PON) for the design and construction of optical access networks for fibre to the home (FTTH). Source ITU-T Recommendation L.52 was approved on
3、14 May 2003 by ITU-T Study Group 6 (2001-2004) under the ITU-T Recommendation A.8 procedure. ii ITU-T Rec. L.52 (05/2003) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications. The ITU Telecommunication Standardization Se
4、ctor (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 view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets eve
5、ry 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 Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purvie
6、w, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is volunt
7、ary. However, the Recommendation may contain certain mandatory provisions (to ensure e.g. interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the n
8、egative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve th
9、e use of a claimed Intellectual Property Right. 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 Recommenda
10、tion, ITU had 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. ITU 20
11、04 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. ITU-T Rec. L.52 (05/2003) iii CONTENTS Page 1 Introduction 1 2 Scope 1 3 References. 1 4 Terms and definitions . 3 5 Abbreviations 3 6 Configurations of PON. 3
12、 6.1 (Fibre optic) branching component in central office 3 6.2 (Fibre optic) branching component in outside plant. 4 6.3 (Fibre optic) branching component in customers building, apartment or residential premises 5 7 Optical fibre distribution method in outside plant 5 8 Optical transmission performa
13、nce for PON . 5 9 Optical components used in PON. 6 9.1 Optical fibre cable 6 9.2 Optical fibre joint . 6 9.3 (Fibre optic) branching component 6 9.4 Other optical components. 8 10 Optical network maintenance support, monitoring and testing system 8 11 Electrical power supply 8 12 Safety 8 12.1 Elec
14、trical safety 8 12.2 Optical safety 8 Appendix I Japanese experience Requirements of a (fibre optic) branching component for outside plant 9 I.1 Access network configuration using a (fibre optic) branching component 9 I.2 Performance of a (fibre optic) branching component for an outside plant. 10 IT
15、U-T Rec. L.52 (05/2003) 1 ITU-T Recommendation L.52 Deployment of Passive Optical Networks (PON) 1 Introduction In order to provide various types of broadband services such as data or video communication, it is important to construct optical access networks economically and effectively for fibre to
16、the home (FTTH). The feature of the passive optical network (PON) is that a (fibre optic) branching component is placed between an optical line terminal (OLT) and several optical network units (ONU). The use of a PON is one of the most cost effective ways of realizing FTTH. Here, an optical access n
17、etwork is defined as a network of optical fibres that extends from a carriers central office into individual homes, apartment houses and business offices for FTTH. 2 Scope This Recommendation deals with the location of (fibre optic) branching components (in central offices, in outside plant or in cu
18、stomers buildings, apartment houses or residential premises) and (fibre optic) branching components, which are the most important items in terms of PON design and construction. Moreover, this Recommendation describes the optical transmission performance and a maintenance system developed to design a
19、nd construct optical access networks for FTTH. 3 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 Recommendati
20、ons and other references are subject to revision; 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 publis
21、hed. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. 1 ITU-T Recommendation G.652 (2003), Characteristics of a single-mode optical fibre cable. 2 ITU-T Recommendation G.662 (1998), Generic characteristics of optical
22、amplifier devices and subsystems. 3 ITU-T Recommendation G.664 (2003), Optical safety procedures and requirements for optical transport systems. 4 ITU-T Recommendation G.671 (2002), Transmission characteristics of optical components and subsystems. 5 ITU-T Recommendation G.694.1 (2002), Spectral gri
23、ds for WDM applications: DWDM frequency grid. 6 ITU-T Recommendation G.694.2 (2003), Spectral grids for WDM applications: CWDM wavelength grid. 7 ITU-T Recommendation G.982 (1996), Optical access networks to support services up to the ISDN primary rate or equivalent bit rates. 8 ITU-T Recommendation
24、 G.983.1 (1998), Broadband optical access systems based on passive optical networks (PON). 9 ITU-T Recommendation G.983.2 (2002), ONT management and control interface specification for B-PON. 2 ITU-T Rec. L.52 (05/2003) 10 ITU-T Recommendation G.983.3 (2001), A broadband optical access system with i
25、ncreased service capability by wavelength allocation. 11 ITU-T Recommendation G.983.4 (2001), A broadband optical access system with increased service capability using dynamic bandwidth assignment (DBA). 12 ITU-T Recommendation G.983.5 (2002), A broadband optical access system with enhanced survivab
26、ility. 13 ITU-T Recommendation G.983.6 (2002), ONT management and control interface specifications for B-PON system with protection features. 14 ITU-T Recommendation G.983.7 (2001), ONT management and control interface specification for dynamic bandwidth assignment (DBA) B-PON system. 15 ITU-T Recom
27、mendation G.983.8 (2003), B-PON OMCI support for IP, ISDN, video, VLAN tagging, VC cross-connections and other select functions. 16 ITU-T Recommendation G.984.1 (2003), Gigabit-capable Passive Optical Networks (GPON): General characteristics. 17 ITU-T Recommendation K.51 (2000), Safety criteria for
28、telecommunication equipment. 18 ITU-T Recommendation L.10 (2002), Optical fibre cables for duct and tunnel application. 19 ITU-T Recommendation L.12 (2000), Optical fibre joints. 20 ITU-T Recommendation L.13 (2003), Performance requirements for passive optical nodes: sealed closures for outdoor envi
29、ronments. 21 ITU-T Recommendation L.15 (1993), Optical local distribution networks Factors to be considered for their construction. 22 ITU-T Recommendation L.26 (2002), Optical fibre cables for aerial application. 23 ITU-T Recommendation L.31 (1996), Optical fibre attenuators. 24 ITU-T Recommendatio
30、n L.36 (1998), Single mode fibre optic connectors. 25 ITU-T Recommendation L.37 (1998), Fibre optic (non-wavelength selective) branching devices. 26 ITU-T Recommendation L.40 (2000), Optical fibre outside plant maintenance support, monitoring and testing system. 27 ITU-T Recommendation L.41 (2000),
31、Maintenance wavelength on fibres carrying signals. 28 ITU-T Recommendation L.42 (2003), Extending optical fibre solutions into the access network. 29 ITU-T Recommendation L.43 (2002), Optical fibre cables for buried application. 30 ITU-T Recommendation L.44 (2000), Electric power supply for equipmen
32、t installed as outside plant. 31 ITU-T Recommendation L.50 (2003), Requirements for passive optical nodes: optical distribution frames for central office environments. 32 ITU-T Recommendation L.51 (2003), Passive node elements for fibre optic networks General principles and definitions for character
33、ization and performance evaluation. 33 ITU-T Recommendation L.53 (2003), Optical fibre maintenance criteria for access networks. 34 IEC 60825 (2001), Safety of laser products. ITU-T Rec. L.52 (05/2003) 3 35 IEC 60950 (2001), Information technology equipment Safety. 4 Terms and definitions For the pu
34、rpose of this Recommendation, the definitions given in ITU-T Recs G.652, G.662, G.671, G.694.1, G.694.2, G.982, G.983.1 to G.983.8, G.984.1, K.51, L.13, L.26, L.42 and L.51 apply. 5 Abbreviations This Recommendation uses the following abbreviations: CATV Cable Television FTTH Fibre To The Home OLT O
35、ptical Line Terminal ONU Optical Network Unit PON Passive Optical Network WDM Wavelength Division Multiplexing 6 Configurations of PON In order to select a PON, telecommunication companies should consider the following: 1) the number and density of customers (including future demand); 2) constructio
36、n and maintenance costs; 3) scalability (number of terminated fibres, total fibre length of network, etc.); 4) the optical network monitor and testing system. Based on the requirements of PONs in each region, telecommunication companies should select one or more of the following locations for the (f
37、ibre optic) branching component, according to the practical feature when designing or constructing a PON. Moreover, telecommunication companies should select the (fibre optic) branching component taking into account the factors and performances as described in 9.3. 6.1 (Fibre optic) branching compon
38、ent in central office The basic configuration for a (fibre optic) branching component used in a central office is shown in Figure 1. Here, there is at least one fibre between the central office and the customers building, apartment house or residential premises. Therefore, a large number of fibres a
39、re installed and distributed from the central office. When an optical network monitoring and testing system is installed between a (fibre optic) branching component and an ONU in a central office, an individual optical fibre to a customer can be monitored and tested using the same method and functio
40、ns as those employed for a point-to-point network as described in ITU-T Rec. L.40, because the test light can be launched in an individual optical fibre. When the transmission capacity, transmission length or/and number of customers increases and optical network upgrade is necessary, the telecommuni
41、cation companies should consider the method indicated in Table 1/L.42. 4 ITU-T Rec. L.52 (05/2003) L.052_F01Central officeOLTONUONUONUONUOptical fibreFibre optic branching componentBuilding, apartment house orresidential premisesOLT Optical Line TerminalONU Optical Network UnitFigure 1/L.52 PON conf
42、iguration using (fibre optic) branching components for a central office (with 4 branches) 6.2 (Fibre optic) branching component in outside plant The basic configuration for a (fibre optic) branching component used in an outside plant for a PON is shown in Figure 2. The (fibre optic) branching compon
43、ent is located in a closure or cabinet in the outside plant. Therefore, the number of distributed fibres between an OLT and a (fibre optic) branching component can be reduced. When an optical network monitoring and testing system is established between an OLT and a (fibre optic) branching component
44、in a central office, any individual outside plant optical fibre to (fibre optic) branching components can be monitored and tested by using the same method and functions employed for a point-to-point network as described in ITU-T Rec. L.40. However, additional functions, besides those indicated in IT
45、U-T Rec. L.40, are required when an individual optical fibre from a (fibre optic) branching component to an ONU is monitored and tested. When the transmission capacity, transmission length or/and number of customers increases and optical network upgrade is necessary, the telecommunication companies
46、should consider the method indicated in Table 1/L.42. L.052_F02Central officeOLTONUONUONUONUOptical fibreFibre optic branching componentBuilding, apartment house orresidential premisesOLT Optical Line TerminalONU Optical Network UnitFigure 2/L.52 PON configuration using (fibre optic) branching compo
47、nents for an outside plant (with 4 branches) ITU-T Rec. L.52 (05/2003) 5 6.3 (Fibre optic) branching component in customers building, apartment or residential premises The basic configuration of a (fibre optic) branching component used in a customers building, apartment or residential premises is sh
48、own in Figure 3. The (fibre optic) branching component is installed inside the customers building, apartment or residential premises. Therefore, a small number of fibres can be installed and distributed between an OLT and a fibre optic branching component. Moreover, this is available when several ON
49、Us in one customers building, apartment or residential premises are used. When an optical network monitoring and testing system is set up between an OLT and a (fibre optic) branching component in a central office, any individual optical fibre connected to the (fibre optic) branching component can be monitored and tested using the same method and functions used for a point-to-point network as described in ITU-T Rec. L.40. However, additional functions, besides those indicated in ITU-T Rec. L.40, ar
