1、 I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n ITU-T G.989 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (10/2015) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Digital sections and digital line system Optical line systems for local and access netwo
2、rks 40-Gigabit-capable passive optical networks (NG-PON2): Definitions, abbreviations and acronyms Recommendation ITU-T G.989 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS G.100G.199 GENERAL CHARACTERISTIC
3、S COMMON TO ALL ANALOGUE CARRIER-TRANSMISSION SYSTEMS G.200G.299 INDIVIDUAL 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 L
4、INES G.400G.449 COORDINATION OF RADIOTELEPHONY AND LINE TELEPHONY G.450G.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 opti
5、cal fibre cable systems G.910G.919 Digital sections at hierarchical bit 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.
6、950G.959 Digital section and digital transmission systems for customer access to ISDN G.960G.969 Optical fibre submarine cable systems G.970G.979 Optical line systems for local and access networks G.980G.989 Metallic access networks G.990G.999 MULTIMEDIA QUALITY OF SERVICE AND PERFORMANCE GENERIC AN
7、D USER-RELATED ASPECTS G.1000G.1999 TRANSMISSION MEDIA CHARACTERISTICS G.6000G.6999 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.989 (10/20
8、15) i Recommendation ITU-T G.989 40-Gigabit-capable passive optical networks (NG-PON2): Definitions, abbreviations and acronyms Summary Recommendation ITU-T G.989 contains the common definitions, acronyms, abbreviations and conventions of the ITU-T G.989-series of Recommendations. History Edition Re
9、commendation Approval Study Group Unique ID* 1.0 ITU-T G.989 2015-10-22 15 11.1002/1000/12561 * To access the Recommendation, type the URL http:/handle.itu.int/ in the address field of your web browser, followed by the Recommendations unique ID. For example, http:/handle.itu.int/11.1002/1000/11830-e
10、n. ii Rec. ITU-T G.989 (10/2015) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of I
11、TU. 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 every four years, establishes the topics
12、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 purview, the necessary standards are prepare
13、d 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 voluntary. However, the Recommendation may c
14、ontain 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 negative equivalents are used to expr
15、ess requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTSITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Prope
16、rty 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 Recommendation, ITU had not received notice of
17、intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementers 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 2015 Al
18、l rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T G.989 (10/2015) iii Table of Contents Page 1 Scope . 1 2 References . 1 3 Definitions 1 3.1 Terms defined elsewhere 1 3.2 Terms defined in this Recommend
19、ation . 2 4 Abbreviations and acronyms 10 5 Conventions 16 5.1 Optical access concepts 16 5.2 Multi-wavelength PON system reference points 17 5.3 Optical power and loss parameters . 18 5.4 Dynamic range, sensitivity and overload . 18 5.5 Sensitivity and overload in the presence of FEC 19 5.6 Reach a
20、nd distance . 19 5.7 Use of the term PON 20 5.8 Use of the term ODN 20 5.9 Use of the terms ONU and ONT 21 5.10 Use of the terms T-CONT and Alloc-ID 21 5.11 Use of the terms bandwidth assignment and bandwidth allocation . 22 5.12 Use of the terms band and range 22 5.13 Transmitter enable control and
21、 associated transient times . 22 Bibliography. 24 Rec. ITU-T G.989 (10/2015) 1 Recommendation ITU-T G.989 40-Gigabit-capable passive optical networks (NG-PON2): Definitions, abbreviations and acronyms 1 Scope This Recommendation contains the common definitions, acronyms, abbreviations and convention
22、s of the ITU-T G.989-series of Recommendations. 2 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 Recommendat
23、ions 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 publi
24、shed. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T J.185 Recommendation ITU-T J.185 (2012), Transmission equipment for transferring multi-channel television signals over optical access networks by frequency
25、modulation conversion. ITU-T J.186 Recommendation ITU-T J.186 (2008), Transmission equipment for multi-channel television signals over optical access networks by sub-carrier multiplexing (SCM). 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the following terms defined elsewhere:
26、3.1.1 access network (AN) b-ITU-T G.902: An implementation comprising those entities (such as cable plant, transmission facilities, etc.) which provide the required transport bearer capabilities for the provision of telecommunications services between a service node interface (SNI) and each of the a
27、ssociated user-network interfaces (UNIs). 3.1.2 Ethernet LAN service (E-LAN) b-MEF 6.1: An Ethernet service type that is based on a Multipoint-to-Multipoint Ethernet virtual connection. 3.1.3 Ethernet line service (E-Line) b-MEF 6.1: An Ethernet service type that is based on a Point-to-Point Etherne
28、t virtual connection. 3.1.4 Ethernet tree service (E-Tree) b-MEF 6.1: An Ethernet service type that is based on a Rooted-Multipoint Ethernet virtual connection. 3.1.5 Ethernet virtual connection (EVC) b-MEF 6.1: An association of UNIs to which the exchange of service frames is limited. 3.1.6 jitter
29、(timing jitter) b-ITU-T G.810: The short-term variations of the significant instances of a digital signal from their ideal positions in time (where “short-term“ implies that these variations are of a frequency greater than or equal to 10 Hz). 2 Rec. ITU-T G.989 (10/2015) 3.1.7 service node (SN) b-IT
30、U-T G.902: A network element that provides access to various switched and/or permanent telecommunication services. 3.1.8 service node interface (SNI) b-ITU-T G.902: An interface which provides customer access to a service node. 3.1.9 user-network interface (UNI) b-ITU-T I.112: The interface between
31、the terminal equipment and a network termination at which interface the access protocols apply. 3.1.10 1:1 VLAN b-BBF TR-101: A VLAN forwarding paradigm involving a one-to-one mapping between user port and VLAN. The uniqueness of the mapping is maintained in the Access Node and across the Aggregatio
32、n Network. 3.1.11 N:1 VLAN b-BBF TR-101: A VLAN forwarding paradigm involving many-to-one mapping between user ports and VLAN. The user ports may be located in the same or different Access Nodes. 3.2 Terms defined in this Recommendation This Recommendation defines the following terms: 3.2.1 Optical
33、access architecture terms 3.2.1.1 channel group: A set of channel pairs carried over a common fibre. 3.2.1.2 channel pair: A set of one downstream wavelength channel and one upstream wavelength channel that provides connectivity between an OLT and one or more ONUs. 3.2.1.3 channel partition: Any of
34、the operator-specified non-overlapping subsets of TWDM or PtP WDM channels in an NG-PON2 system. 3.2.1.4 channel partition index: An identity of an operator-specified TWDM or PtP WDM channel subset in an NG-PON2 system. 3.2.1.5 channel termination (CT): See OLT PtP WDM channel termination, OLT TWDM
35、channel termination. 3.2.1.6 coexistence element: A bidirectional functional element used to connect PON systems defined in different Recommendation series to the same ODN. 3.2.1.7 domain: A collection of all NG-PON2 network elements under a common and unique operational administration. 3.2.1.8 giga
36、bit-capable passive optical network (G-PON): A PON system supporting transmission rates in excess of 1.0 Gbit/s in at least one direction, and which implements the suite of protocols specified in the ITU-T G.984-series of Recommendations. 3.2.1.9 next generation PON (NG-PON): In the context of ITU-T
37、 standards development activity, a generic term referencing the PON system evolution beyond G-PON. The concept of NG-PON currently includes NG-PON1, where the ODN is maintained from B-PON and G-PON, and NG-PON2, where a redefinition of the ODN is allowed from that defined in B-PON and G-PON. 3.2.1.1
38、0 NG-PON1: A PON system with a nominal aggregate capacity of 10 Gbit/s in the downstream direction. The NG-PON1 system is represented by XG-PON. 3.2.1.11 NG-PON2: A PON system with a nominal aggregate capacity of 40 Gbit/s in the downstream direction and 10 Gbit/s in the upstream direction, and impl
39、ementing the suite of protocols specified in the ITU-T G.989-series of Recommendations. An NG-PON2 system is composed of a set of TWDM channels and/or a set of PtP WDM channels. Rec. ITU-T G.989 (10/2015) 3 3.2.1.12 OLT PtP WDM channel termination: A logical function that resides at the OLT network
40、element and terminates a single PtP WDM channel in a PtP WDM system. 3.2.1.13 OLT TWDM channel termination: A logical function that resides at the OLT network element and that terminates a single TWDM channel in a TWDM system. 3.2.1.14 optical access network (OAN): A part of an access network whose
41、network elements are interconnected by optical communication channels. Note that an OAN may or may not extend all the way to the UNI, so that the user-side interface of the OAN does not necessarily coincide with the UNIs of the AN. 3.2.1.15 optical distribution network (ODN): A point-to-multipoint o
42、ptical fibre infrastructure. A simple ODN is entirely passive and is represented by a single-rooted point-to-multipoint tree of optical fibres with splitters, combiners, filters and possibly other passive optical components. A composite ODN consists of two or more passive segments interconnected by
43、active devices, each of the segments being either an optical trunk line segment or an optical distribution segment. A passive optical distribution segment is a simple ODN itself. Two ODNs with distinct roots can share a common subtree. 3.2.1.16 optical distribution segment (ODS): A simple ODN, that
44、is, a point-to-multipoint optical fibre infrastructure that is entirely passive and is represented by a single-rooted tree of optical fibres with splitters, combiners, filters and possibly other passive optical components. 3.2.1.17 optical line termination (OLT): A network element in an ODN-based op
45、tical access network that terminates the root of at least one ODN and provides an OAN SNI. 3.2.1.18 optical network terminal (ONT): An ONU supporting a single subscriber. 3.2.1.19 optical network unit (ONU): A network element in an ODN-based optical access network that terminates a leaf of the ODN a
46、nd provides an OAN UNI. 3.2.1.20 optical trunk line (OTL): A passive point-to-point segment of a composite ODN. 3.2.1.21 parenting: A passive optical network protection configuration where ONUs are connected to two CTs hosted in different OLT chassis. Typically, the OLT chassis in dual parenting are
47、 geographically remote from each other. 3.2.1.22 passive optical network (PON) system: A combination of network elements in an ODN-based optical access network that includes an OLT and one or more ONUs and implements a particular coordinated suite of physical medium dependent layer, transmission con
48、vergence layer and management protocols. 3.2.1.23 PtP WDM channel: In an NG-PON2 system, PtP WDM channel refers to the pair of one downstream wavelength channel and one upstream wavelength channel providing point-to-point connectivity. 3.2.1.24 PtP WDM PON: A multiple wavelength PON system that enab
49、les point-to-point connectivity using a dedicated wavelength channel per ONU for the downstream direction and a dedicated wavelength channel per ONU for the upstream direction. 3.2.1.25 RF video overlay: A method for video transmission in the downstream direction in a wavelength band between 1550 nm and 1560 nm according to ITU-T J.185 and ITU-T J.186. 3.2.1.26 TWDM channel: In an NG-PON2 system, TWDM channel refers to the pair of one downstream wavelength channel and one upstream wavelength channel providing poin
