1、 STDmITU-T RECMN 1.LOSO-ENGL 1998 = 48b259L Ob53330 OTT W INTERNATIONAL TELECOMMUNICATION UNION ITUmT TELECOMMUNICATION STAN DARD IZATI ON SECTOR OF ITU M.1050 (06/98) SERIES M: TMN AND NETWORK MAINTENANCE: INTERNATIONAL TRANSMISSION SYSTEMS, TELEPHONE CIRCUITS, TELEGRAPHY, FACSIMILE AND LEASED CIRC
2、UITS International leased circuits Lining up an international point-to-point leased circuit with analogue presentation to the user ITU-T Recommendation M.1050 (Previously CCITT Recommendation) 1TU-T M-SERIES RECOMMENDATIONS TMN AND NETWORK MAINTENANCE: INTERNATIONAL TRANSMISSION SYSTEMS, TELEPHONE C
3、IRCUITS, TELEGRAPHY, FACSIMILE AND LEASED CIRCUITS Introduction and general principles of maintenance and maintenance organization International transmission systems M.30-M.559 M. 10-M.299 Mobile telecommunication systems and services International public telephone network International data transmi
4、ssion systems Designations and information exchange International transport network Telecommunications management network Integrated services digital networks Common channel signalling systems International telephone circuits Common channel signalling systems International telegraph systems and phot
5、otelegraph transmission I M.560-M.759 M.760-M.799 M.800-M.899 International leased group and supergroup links International leased circuits M.1000-M.1099 M.900-M.999 M.1100-M.1199 M.1200-M.1299 M. 1300-M. 1399 M. 140-M. 1999 M .2000-M .2999 M.3000-M.3599 M.3600-M.3999 M.4000-M.4999 For further detai
6、ls, please refer to ITU-T List of Recommendations. STD-ITU-T RECNN N.LO50-ENGL 1998 4862571 Ob53332 972 ITU-T RECOMMENDATION M.1050 LINING UP AN INTERNATIONAL POINT-TO-POINT LEASED CIRCUIT WITH ANALOGUE PRESENTATION TO THE USER Summary This Recommendation provides two methodologies to ensure effecti
7、ve lining up of an international leased circuit with analogue presentation to the user. Source ITU-T Recommendation M. 1 O50 was revised by ITU-T Study Group 4 (1 997-2000) and was approved under the WTSC Resolution No. 1 procedure on the 26th of June 1998. Keywords Analogue presentation, end-to-end
8、 line up, international leased circuit, section-by-section line up. Recommendation M.1050 (0698) i FOREWORD ITU (International Telecommunication Union) is the United Nations Specialized Agency in the field of telecommuni- cations. The ITU Telecommunication Standardization Sector (ITU-T) is a permane
9、nt organ of the ITU. The 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 Conference (WTSC), which meets every four years,
10、establishes the topics for study by the ITU-T Study Groups which, in their turn, produce Recommendations on these topics. The approval 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 wit
11、hin IT-Ts purview, the necessary standards are prepared on a collaborative basis with IS0 and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. INTELLECTUAL PROPERTY RIGHTS
12、The ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. The ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted b
13、y ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, the ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementors are cautioned th
14、at this may not represent the latest information and are therefore strongly urged to consult the TSB patent database. O ITU 1998 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,
15、 without permission in writing from the ITU. 11 Recommendation M.1050 (06/98) . STDmITU-T RECMN M.LO5O-ENGL 1998 m 48b2591 Ob53334 745 m 1 2 3 4 5 6 7 8 CONTENTS Page Scope References Terminology and definitions Abbreviations . General . Lining up the constituent parts of the circuit 6.1 National se
16、ctions . Overall loss at reference frequency . Losslfrequency distortion (special quality circuits only) Group-delay distortion (special quality circuits only) . 6.2 International section Overall loss at reference frequency . 6.2.2 Losslfrequency distortion Group-delay distortion (special quality ci
17、rcuits only) . 6.3 International link . Lining up the overall circuit . 6.1.1 6.1.2 6.1.3 6.2.1 6.2.3 7.1 7.2 7.3 7.4 7.5 7.6 7.7 7.8 7.9 7.10 7.11 7.12 7.13 Overall loss . Losslfrequency distortion 7.2.1 Ordinary quality circuits 7.2.2 Special quality circuits Group-delay distortion (special qualit
18、y circuits only) . Variation with time of the overall loss at 1020 Hz . 7.4.1 7.4.2 Other variations . Random circuit noise . impulsive noise (special quality circuits only) Phase jitter (special quality circuits only) . Total distortion (special quality circuits only) Amplitude hits (special qualit
19、y circuits only) Single tone interference (special quality circuits only) . Frequency error (special quality circuits only) . . Harmonic and intermodulation distortion (special quality circuits only) Crosstalk (special quality circuits only) Power source interferences (special quality circuits only)
20、 . Section-by-section line-up Lining up the analogue-type section . 8.1.1 National sections . 8.1.2 International section Lining up the digital-type section . 8.2.1 National sections . 8.2.2 International section 8.1 8.2 Recommendation M.1050 (06/98) 1 1 2 2 3 3 3 3 4 4 4 4 4 4 4 4 5 5 5 5 5 6 6 6 6
21、 6 6 6 7 7 7 7 7 7 8 8 10 10 10 11 . 111 9 10 11 12 13 14 8.3 Overall circuit . Configuration and testing of digital-type sections bounded by A/D converters . 8.3.2 Overall lineup Additional reference measurements Functional checks . Transmission level checks Level limiters Marking of equipment asso
22、ciated with special quality circuits 8.3.1 Short-time rerouting of special quality leased circuits . Page 11 11 11 11 11 12 12 12 12 iv Recommendation M.1050 (06/98) Recommendation M.1050 LINING UP AN INTERNATIONAL POINT-TO-POINT LEASED CIRCUIT WITH ANALOGUE PRESENTATION TO THE USER Published as M.8
23、9 in 1964; revised and renumbered as M. 1 O2 in 1968; new as M. I Il and M.1 I3 in 1968; revised in 1972; combined with M. 102 (part), Ml11 (part) andM.113 andrevised in 1976; renumberedM.1050 in 1980; revised in 1984, 1988, I993 and 19981 1 Scope This Recommendation deals with the lining-up of both
24、 ordinary quality point-to-point leased circuits (the characteristics of which are specified in Recommendation M.1040 15), and special quality point-to-point leased circuits (the characteristics of which are specified in Recommendations M.1020 12 and M.1025 13), which are provided by analogue transm
25、ission systems or by a mixture of analogue and digital systems. 2 References The following ITU-T Recommendations 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
26、are subject to revision; all users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendation listed below. A list of the currently valid ITU-T Recommendations is regularly published. ITU-T Recommendation G. 1 O 1 (1996),
27、The transmission plan. ITU-T Recommendation G. 122 (1993), Influence of national systems on stability and talker echo in international connections. ITU-T Recommendation G. 13 1 (1996), Control of talker echo. CCITT Recommendation G. 134 (1988), Linear crosstalk. CCITT Recommendation G. 15 1 (1980),
28、General performance objectives applicable to all modern international circuits and national extension circuits. CCITT Recommendation G.224 (1 984), Maximum permissible value for the absolute power level (power referred to one milliwatt) of a signalling pulse. CCITT Recommendation G.232 (1984), 12-ch
29、annel terminal equipments. CCITT Recommendation H. 13 (1 988), Impulsive-noise measuring instrument for telephone-Qpe circuits. ITU-T Recommendation M.60 (1 993), Maintenance terminology and dejnitions. CCITT Recommendation M.580 (1988), Setting up and lining up an international circuit for public t
30、elephony. CCITT Recommendation M. 1 O 1 O (1988), Constitution und nomenclature of international leased circuits. ITU-T Recommendation M. 1020 (1 993), Characteristics of special quality international leased circuits with special bandwidth conditioning. ITU-T Recommendation M. 1025 (1 993), Characte
31、ristics of special quality international leased circuits with basic bandwidth conditioning. CCITT Recommendation M. 1030 (1988), Characteristics of ordinary quality international leased circuits forming part ofprivate switched telephone networks. Recommendation M.1050 (0698) 1 151 CCITT Recommendati
32、on M. 1040 (1 988), Characteristics ofordinary quality international leased circuits. 161 CCITT Recommendation M. 1060 (1 SU), Maintenance of international leased circuits. 171 ITU-T Recommendation M.1340 (1996), Performance allocations and limits for international data transmission links and system
33、s. 181 ITU-T Recommendation M. 1370 (1993), Bringing-into-service of international data transmission systems. 191 ITU-T Recommendation M.2100 (1995), Performance limits for bringing-into-service and maintenance of international PDHpath, sections and transmission systems. 20 2 11 ITU-T Recommendation
34、 0.41 (1994), Psophometer for use on telephone-type circuits. CCITT Recommendation 0.7 1 (1988), Impulsive noise measuring equipment for telephone-type circuits. 22 23 24 CCITT Recommendation 0.8 1 (1 972), Group-delay measuring equipment for telephone-type circuits. CCITT Recommendation 0.9 1 (1988
35、), Phase jitter measurement equipment for telephone-type circuits. CCITT Recommendation 0.95 (1980), Phase and amplitude hits counters for telephone-type circuits. 25 26 CCITT Recommendation 0.1 11 (1988), Frequency shifr measuring equipment for use on carrier channels. CCITT Recommendation O. 132 (
36、1 988), Quantizing distortion measuring equipment using a sinusoidal test signal. CCITT Recommendation M.810 (1988), Setting up and lining up of an international voice-frequency telegraph link for public telegraph circuits flor 50, 100 and 200 baud modulation rates). CCITT Recommendation V.2 (1988),
37、 Power levels for data transmission over telephone lines. 27 28 29 CCITT Recommendation V.55 (1 988), Impulsive noise measuring instrument for telephone-type circuits. 30 CCITT Recommendation 0.42 (1984), Equipment to measure non-linear distortion using the 4-tone intermodulation method. 3 Terminolo
38、gy and definitions Terminologies and definitions relating to this Recommendation are provided in Recommendation M.60 9. 4 Abbreviations This Recommendation uses the following abbreviations. m ES FDM PCM Rp SES TIC TNC 2 Analoguemigital Errored Second Frequency Division Multiplexing Pulse Code Modula
39、tion Renters Premises Severely Errored Second Terminal International Centre Terminai National Centre Recommendation M.1050 (06198) STD-ITU-T RECMN M-LOSO-ENGL 1998 a 48b259L Ob53338 390 5 General Figure 1 shows the constituent parts of an international point-to-point leased circuit. RP TNC TIC TIC T
40、NC RP n n I I I I I I I I I h I I I I International section I I I ! I I IA Nationa! section (International line) National section i .IA v- I- d I I I International link I I International leased circuit I G I I ! I .- RP Rentets premises TNC Terminal national centre TIC Terminal international centre
41、I T0405040-4/d01 Figure 1/M.1050 - The constituent parts of an international point-to-point leased circuit Test signals transmitted over the international section and link should be applied at a level of -10 dBmO. The method of line-up described in clauses 6 and 7 below requires that appropriate per
42、sonne1 be present at the renters premises in the two terminal countries to carry out overall, end-to-end tests of the characteristics of international leased circuits. The cooperation of staff at the terminal international centres may also be required to overcome language or technical difficulties.
43、Recognizing that differing national practices may mean that the required degree of international coordination is difficult to achieve, and acknowledging that it may not be possible to arrange simultaneous attendance at the two renters premises because of time zone differences or restricted access to
44、 those premises, clause 8 below describes a method of circuit line-up using a section-by-section approach. it should be noted that the end-to-end line-up approach (see clauses 6 and 7) and the section-by-section approach (see clause 8) are not compatible. Thus, Network Operators/Service Providers mu
45、st agree, on a bilateral basis, which approach they will adopt. When a section is entirely routed over a digital transmission system, the section-by-section approach is preferred. 6 Lining up the constituent parts of the circuit After the circuit has been set up, the following lining-up procedure sh
46、ould be followed in each direction of transmission. 6.1 National sections When analogue access to the circuit is available at the terminal international centre, the following tests should be performed regardless of whether the national section is provided by analogue circuit sections or a combinatio
47、n of analogue, mixed and digital circuit sections. 6.1.1 Overall loss at reference frequency Each national section should be lined up at the reference frequency according to national practices between the terminal national centre and international centre. Note should be taken of the requirement conc
48、erning the receiving relative level in 2.1M.1020 12, 2.1M.1025 13 and 2.1M.1040 15. For intemational leased circuits forming part of a private switched network, the loss of the national section must be consistent with meeting the required overall loss of the circuit as agreed between Network Operato
49、rs/Service Providers (refer to 2.1/M.1030 and to clause 3M.1030 14). A record should be kept of the levels received (including any measurements made at intermediate national test points). National sections beyond the terminal national centre must also be lined up. Recommendation M.1050 (06/98) 3 STD-ITU-T RECMN M.1050-ENGL 1998 m 4862591 Ob53339 227 m 6.1.2 Loss/frequency distortion (special quality circuits only) The losdfrequency distortion should be measured at several frequencies. The limits of Table lM.580 lo
