1、 INTERNATIONAL TELECOMMUNICATION UNION ITU-T G.101TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (11/2003) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS International telephone connections and circuits General definitions The transmission plan ITU-T Recommendation G.101 ITU
2、-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS G.100G.199 General definitions G.100G.109 General Recommendations on the transmission quality for an entire international telephone connection G.110G.119 General
3、characteristics of national systems forming part of international connections G.120G.129 General characteristics of the 4-wire chain formed by the international circuits and national extension circuits G.130G.139 General characteristics of the 4-wire chain of international circuits; international tr
4、ansit G.140G.149 General characteristics of international telephone circuits and national extension circuits G.150G.159 Apparatus associated with long-distance telephone circuits G.160G.169 Transmission plan aspects of special circuits and connections using the international telephone connection net
5、work G.170G.179 Protection and restoration of transmission systems G.180G.189 Software tools for transmission systems G.190G.199 GENERAL CHARACTERISTICS COMMON TO ALL ANALOGUE CARRIER-TRANSMISSION SYSTEMS G.200G.299 INDIVIDUAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LI
6、NES 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.450G.499 TESTING EQUIPMENTS G.500G.599 TRANSMISSION MEDIA CHARACTERISTICS G.600G.
7、699 DIGITAL TERMINAL EQUIPMENTS G.700G.799 DIGITAL NETWORKS G.800G.899 DIGITAL SECTIONS AND DIGITAL LINE SYSTEM G.900G.999 QUALITY OF SERVICE AND PERFORMANCE GENERIC AND USER-RELATED ASPECTS G.1000G.1999 TRANSMISSION MEDIA CHARACTERISTICS G.6000G.6999 DIGITAL TERMINAL EQUIPMENTS G.7000G.7999 DIGITAL
8、 NETWORKS G.8000G.8999 For further details, please refer to the list of ITU-T Recommendations. ITU-T Rec. G.101 (11/2003) i ITU-T Recommendation G.101 The transmission plan Summary This Recommendation provides guidance for transmission planning of modern telecommunication networks. The primary empha
9、sis is on provisioning of telephone connections. The transmission plan established by this Recommendation takes into account transmission parameters and impairments, different network configurations and elements and modern transmission techniques, as well as the effects resulting from the combinatio
10、n of the various factors having influence on the resulting transmission quality. Source ITU-T Recommendation G.101 was approved by ITU-T Study Group 12 (2001-2004) under the ITU-T Recommendation A.8 procedure on 13 November 2003. ii ITU-T Rec. G.101 (11/2003) FOREWORD The International Telecommunica
11、tion Union (ITU) is the United Nations specialized agency in the field of telecommunications. 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 v
12、iew 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 Recommend
13、ations 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 concis
14、eness 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 Recommendati
15、on 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. IN
16、TELLECTUAL 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 Rights,
17、 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, implementors a
18、re cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database. ITU 2004 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. G.101 (11
19、/2003) iii CONTENTS Page 1 Scope 1 2 References. 1 3 Terms and definitions . 3 4 Abbreviations 3 5 Fundamental principles of transmission planning 3 6 Basic reference model and definitions 6 6.1 Reference model. 6 6.2 Relative levels 7 6.3 Circuits and connections. 8 7 Typical network components and
20、 configurations. 8 7.1 Network components 8 7.2 Network configurations 9 8 Technical requirements/Transmission impairments. 11 8.1 Loudness ratings. 11 8.2 Noise, crosstalk and group delay distortion . 12 8.3 Stability control by loss allocation to circuits 12 8.4 Delay/echo 14 8.5 Packet loss 15 8.
21、6 The effect of coding and signal processing in the digital path. 15 8.7 Channel compression techniques . 15 8.8 Bit integrity. 15 8.9 Bit error performance . 16 8.10 Synchronization 16 8.11 Attenuation distortion. 16 8.12 Effect of syllable speech clipping. 16 8.13 Evaluation of impairments, singly
22、 and in combination 16 9 Service planning and QoS aspects 17 Annex A Terminology used in traditional transmission planning 17 A.1 Circuits and connections. 17 Appendix I Traditional network planning in a regulated environment by subdividing an international connection into “national systems“ and an
23、“international chain“ 20 I.1 Subdivision of telephone networks with regard to the interfaces between network operators . 20 I.2 General . 20 I.3 The national systems and the international chain of circuits 20 I.4 Multi-operator networks. 24 iv ITU-T Rec. G.101 (11/2003) Introduction The goal of this
24、 transmission plan is to facilitate interconnection of all communication-related devices (terminals, network elements, public networks, private networks, etc.), independent of technology, so that end-user applications experience no unsatisfactory or annoying impairments. For speech applications this
25、 means the delivery of highly intelligible, natural-sounding speech signals at near-optimum acoustic levels, and free of bothersome levels of distortion, echo, and delay. For non-speech applications, this means that associated transactions (e.g., fax, interactive data, e-mail, web browsing, video st
26、reaming) can be completed satisfactorily. This plan allows for service provider solutions that meet or exceed these criteria. Conversely, if an end user or network operator chooses network elements that cannot support this criterion, they do so with the understanding that all applications may not pe
27、rform satisfactorily and thus interconnection to their network by other network operators may not be desirable. ITU-T Rec. G.101 (11/2003) 1 ITU-T Recommendation G.101 The transmission plan 1 Scope This Recommendation applies to the transmission planning necessitated by telecom deregulation, and in
28、particular, the division of responsibility if multiple network operators are involved in a given connection. The aim of this Recommendation is to provide guidance for transmission planning of telecommunication networks used primarily for narrow-band services. Traditionally this involved a subdivisio
29、n of an international connection into “national systems“ and an “international chain“, usually in a regulated environment. As with previous versions of ITU-T Rec. G.101, this version can be used to do transmission planning for such an environment; however, this version can also be applied to the der
30、egulated multi-operator environment in which there is no clear division of responsibilities. The reference model in this Recommendation is focused on supporting this latter case. The transmission plan established by this Recommendation takes into account transmission parameters and impairments, diff
31、erent network configurations and elements, modern transmission techniques as well as effects resulting from the combination of the various factors having influence on the resulting transmission quality. The main focus of this Recommendation is transmission planning of voice services. Implications as
32、sociated with the planning of other kind of services, e.g., data services, will also be discussed. The transmission plan allows for the adjustment, i.e., staying within acceptable limits, of important transmission parameters and implementation of network configurations and components in order to gua
33、rantee adequate end-to-end transmission performance at all times and under all network-operating conditions. The aim is to allow for flexible control of transmission parameters instead of allocating defined limits. The various transmission parameters are not considered on an individual basis, rather
34、 the combined effects of variations in transmission parameters are assessed. This Recommendation forms a framework for transmission planning. The intention is to: explain basic planning objectives and rules applicable to modern telecommunication networks, list the main technical (transmission) param
35、eters of importance, and provide reference to relevant ITU-T 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 indicat
36、ed were valid. All Recommendations 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 Reco
37、mmendations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T Recommendation G.100 (2001), Definitions used in Recommendations on general characteristics of international telephone connect
38、ions and circuits. ITU-T Recommendation G.100.1 (2001), The use of the decibel and of relative levels in speechband telecommunications. ITU-T Recommendation G.107 (2003), The E-model, a computational model for use in transmission planning. 2 ITU-T Rec. G.101 (11/2003) ITU-T Recommendation G.108 (199
39、9), Application of the E-model: A planning guide. ITU-T Recommendation G.108.1 (2000), Guidance for assessing conversational speech transmission quality effects not covered by the E-model. ITU-T Recommendation G.108.2 (2003), Transmission planning aspects of echo cancellers. ITU-T Recommendation G.1
40、09 (1999), Definition of categories of speech transmission quality. ITU-T Recommendation G.111 (1993), Loudness ratings (LRs) in an international connection. ITU-T Recommendation G.113 (2001), Transmission impairments due to speech processing. ITU-T Recommendation G.113 Appendix I (2002), Provisiona
41、l planning values for the equipment impairment factor Ie and packet-loss robustness factor Bpl. ITU-T Recommendation G.114 (2003), One-way transmission time. ITU-T Recommendation G.115 (1996), Mean active speech level for announcement and speech synthesis systems. ITU-T Recommendation G.116 (1999),
42、Transmission performance objectives applicable to end-to-end international connections. ITU-T Recommendation G.117 (1996), Transmission aspects of unbalance about earth. ITU-T Recommendation G.120 (1998), Transmission characteristics of national networks. ITU-T Recommendation G.121 (1993), Loudness
43、ratings (LRs) of national systems. ITU-T Recommendation G.122 (1993), Influence of national systems on stability and talker echo in international connections. ITU-T Recommendation G.126 (1993), Listener echo in telephone networks. ITU-T Recommendation G.131 (2003), Talker echo and its control. ITU-T
44、 Recommendation G.136 (1999), Application rules for automatic level control devices. ITU-T Recommendation G.142 (1998), Transmission characteristics of exchanges. ITU-T Recommendation G.161 (2002), Interaction aspects of signal processing network equipment. ITU-T Recommendation G.164 (1988), Echo su
45、ppressors. ITU-T Recommendation G.165 (1993), Echo cancellers. ITU-T Recommendation G.167 (1993), Acoustic echo controllers. ITU-T Recommendation G.168 (2002), Digital network echo cancellers. ITU-T Recommendation G.169 (1999), Automatic level control devices. ITU-T Recommendation G.172 (1988), Tran
46、smission plan aspects of international conference calls. ITU-T Recommendation G.173 (1993), Transmission planning aspects of the speech service in digital public land mobile networks. ITU-T Recommendation G.174 (1994), Transmission performance objectives for terrestrial digital wireless systems usin
47、g portable terminals to access the PSTN. ITU-T Rec. G.101 (11/2003) 3 ITU-T Recommendation G.175 (2000), Transmission planning for private/public network interconnection of voice traffic. ITU-T Recommendation G.176 (1997), Planning guidelines for the integration of ATM technology into networks suppo
48、rting voiceband services. ITU-T Recommendation G.177 (1999), Transmission planning for voiceband services over hybrid Internet/PSTN connections. ETSI EN 300 462-1-1 V1.1.1 (1998), Transmission and Multiplexing (TM); Generic requirements for synchronization networks; Part 1-1: Definitions and termino
49、logy for synchronization networks. ETSI EN 300 462-6-1 V1.1.1 (1998), Transmission and Multiplexing (TM); Generic requirements for synchronization networks; Part 6-1: Timing characteristics of primary reference clocks. ISO/IEC 11573:1994, Information technology Telecommunications and information exchange between systems Synchronization methods and technical requirements for Private Integrated Services networks. 3 Terms and definitions This Recommendation defines the following term: 3.
