1、INTERNATIONAL TELECOMMUNICATION UNION ITU=T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU 0.181 SERIES O: SPECIFICATIONS OF MEASURING EQUIPMENT Equipment for the measurement of digital and a na log u e/d ig it a I para meters (0512002) Equipment to assess error performance on STM-N interfaces ITU-
2、T Recommendation O. 181 ITIJ-T O-SERIES RECOMMENDATIONS SPECIFICATIONS OF MEASURING EQUIPMENT General O. 1-0.9 Maintenance access O. 10-0.19 0.20-0.39 Automatic and semi-automatic measuring systems Equipment for the measurement of analogue paramc ers 0.40-0.129 Equipment for the measurement of digit
3、al and analogue/digital parameters 0.130-0.199 For further details, please refer to the list of ITU-T Recommendations. ITU-T Recommendation 0.181 Equipment to assess error performance on STM-N interfaces Summary This Recommendation specifies the measuring equipment and the related test signal struct
4、ures to perform in-service or out-of-service error performance measurements on STM-N interfaces. Source ITU-T Recommendation O. 18 1 was revised by ITU-T Study Group 4 (2001-2004) and approved under the WTSA Resolution 1 procedure on 29 May 2002. Keywords Error performance, in-service, measuring equ
5、ipment, measurement mode, out-of-service, test signal structure. ITU-T Rec. 0.181 (05/2002) 1 FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent
6、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 every four years, establishes t
7、he 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 purview, the necessary standards a
8、re 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 ITU draws attention to the possibility that
9、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, whether asserted by ITU members or others outside of the Recommendatio
10、n 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 are cautioned that this may not represent the latest information and are
11、 therefore strongly urged to consult the TSB patent database. O ITU 2002 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. 0.181 (05/2002) 11 CONTENTS 1 Scope 2 References . 3 Definitions 4 Abbreviatio
12、ns 5 Measurement modes and events to be monitored . 5.1 5.2 5.2.1 5.2.2 5.3 5.3.1 5.3.2 5.3.3 5.3.4 5.3.5 5.3.6 5.3.7 5.3.8 5.3.9 5.4 5.4.1 5.4.2 5.4.3 5.4.4 5.4.5 5.4.6 5.4.7 Definition of the measurement modes Events to be monitored . Network events . Test signal structure events Out-of-service me
13、asurement modes . Mode with higher-order container (C-4) end-to-end transparency Mode with higher-order container (C-3) end-to-end transparency Mode with lower-order container (C-3) end-to-end transparency . Mode with lower-order container (C- 1 1/C- 12/C-2) end-to-end transparency Mode with plesioc
14、hronous tributary mapping in a higher-order container (C-4) Mode with plesiochronous tributary mapping in a higher-order container (C-3) . Mode with a plesiochronous tributary mapping in a lower-order container (C-3) . Mode with a plesiochronous tributary mapping in a lower-order container (C-ll/C-1
15、2/C-2) . Mode with contiguous concatenated structures (VC-2-Xc and VC-4-Xc) end-to-end transparency . In-service measurement modes Events to be monitored for a STM-N Regenerator section Events to be monitored for a higher-order container (C-4) Events to be monitored for a higher-order container (C-3
16、) Events to be monitored for a lower-order container (C-3) . Events to be monitored for a lower-order container (C-1 l/C-12/C-2) . Events to be monitored for VC-2-Xc and VC-4-Xc contiguous concatenated structures . Events to be monitored for a Multiplex section . 6 Generator 6.1 6.2 Synchronization
17、of the generator Bit rates . Page 1 1 2 2 3 3 3 3 4 4 5 6 8 8 8 9 9 10 10 10 11 11 11 11 11 12 12 12 12 12 . ITU-T Rec . 0.181 (05/2002) 111 6.3 Test signal structures . : 6.4 Digital signal outputs 6.4.1 Digital interfaces 6.4.2 Output jitter 7 Receiver ;. 7.1 Digital signal inputs 7.1.1 Digital in
18、terfaces 7.1.2 Input jitter tolerance . 7.1.3 Protected monitoring points . 7.3 Error performance measurement 7.2 Test signal structures Error performance measurement using ISM facilities only . Error measurement using both ISM facilities and test sequence information . Use ofthe performance paramet
19、ers 7.3.1 7.3.2 7.3.3 7.3.4 Additional error measurement 8 Miscellaneous functions . 8.1 Display 8.2 8.3 Alarm and error indication . 8.4 Access to overhead bytes 8.5 Demultiplexing capability Anomaly and defect addition on the output signal . 8.6 Events time stamping . 8.7 Output to external record
20、ing devices 8.8 Remote control port 8.9 TMN interface 8.10 Access to Data Communication Channels . 9 Operating conditions . 9.1 Environmental conditions . 9.2 Behaviour in case of power failure . Annex A . Criteria for detecting anomalies and defects . A . 1 Anomalies related to performance measurem
21、ents A.l.l Out of Frame (OOF) . A.1.2 B1 errors . A . 1.3 B2 errors . A.1.4 B3 errors . A . 1.5 A . 1.6 Multiplex Section Remote Error Indication (MS-REI) Higher-order Path Remote Error Indication (HP-RET) Page 12 12 12 12 13 13 13 13 13 13 13 13 17 17 17 17 17 18 18 18 15 18 18 18 18 18 18 18 18 19
22、 19 19 19 19 19 19 19 iv ITU-T Rec . 0.181 (OW2002) A.1.7 A.1.8 A . 1.9 A.2 A.2.1 A.2.2 A.2.3 A.2.4 A.2.5 A.2.6 A.2.7 A.2.8 A.2.9 A.2.10 A.2.11 A.2.12 A.2.13 A.2.14 A.2.15 A.3 A.3.1 A.3.2 A.3.3 A.3.4 A.3.5 A.3.6 A.4 A.4.1 Lower-order Path Remote Error Indication (LP.RE1) BIP-2 errors Test Sequence E
23、rror (TSE) . Defects related to performance measurements . Loss of Signal (LOS) Loss of Frame (LOF) Regenerator Section Trace Identifier Mismatch (RS-TIM) . Multiplex Section Alarm Indication Signal (MS-AIS) Multiplex Section Remote Defect Indication (MS-RDI) . Administrative Unit Loss of Pointer (A
24、U-LOP) Administrative Unit Alarm Indication Signal (AU-AIS) . Higher-order Path Remote Defect Indication (HP-RDI) Higher-order Path Trace Identifier Mismatch (HP-TIM) . Higher-order Path Loss of Multiframe (HP-LOM) Tributary Unit Alarm Indication Signal (TU-AIS) Tributary Unit Loss of Pointer (TU-LO
25、P) Lower-order Path Remote Defect Indication (LP-RDI) . Lower-order Path Trace Identifier Mismatch (LP-TIM) Loss of Sequence Synchronization (LSS) Higher-order Path PayLoad Mismatch (HP-PL M) . Other events not related to performance measurement Lower-order Path PayLoad Mismatch (LP-PLM) Higher-orde
26、r Path unequipped (HP-UNEQ) Lower-order Path unequipped (LP-UNEQ) . . Loss oftiming input Lower-order Path Remote Failure Indication (LP-RFI) . Other information . Pointer Justification Counts (PJC+, PJC-) . Annex B . Classification of SDH available indications . B . 1 Anomaly and defect indications
27、 . Annex C . List of test signal structures . Test signal structure TSS 1 applied to all bytes of a C-4 higher-order container . Test signal structure TSS2 applied to all bytes of a C-3 higher-order container . Test signal structure TSS3 applied to all bytes of a C-3 lower-order container . Test sig
28、nal structure TSS4 applied to all bytes of (C.2, C.12, C-1 1) lower-order containers C . 1 C.2 C.3 C.4 Page 19 19 19 20 20 20 20 20 20 20 20 20 20 20 20 21 21 21 21 21 21 21 21 21 21 21 21 22 22 22 23 23 24 24 25 ITU-T Rec . 0.181 (05/2002) V Page C.5 C.6 C.7 C.8 C.9 C. 1 O Test signal structure TSS
29、5 applied to all PDH tributary bits mapped in a C-4 container Test signal structure TSS6 applied to all PDH tributary bits mapped in a Test signal structure TSS7 applied to all PDH tributary bits mapped in a lower-order C-3 container Test signal structure TSS8 applied to all PDH tributary bits mappe
30、d in a Test signal structure applied to VC-4-Xc contiguous concatenated structures . Test signal structure applied to VC-2-Xc contiguous concatenated structures . higher-order C-3 container . lower-order (C-2, C-1 1, C-12) container Appendix I Examples of measuring equipment connections to network e
31、lements illustrating different out-of-service measurement modes . 25 25 26 26 27 27 28 vi ITU-T Rec. 0.181 (092002) Introduction The requirements for the characteristics of the error performance measuring equipment which are described below must be adhered to in order to ensure compatibility between
32、 equipment produced by different manufacturers. While requirements are given for the equipment, the realization of the equipment configuration is not covered and should be given careful consideration by the designer and user. In particular, it is not required that all features listed below shall be
33、provided in one piece of equipment. Users may select those functions which correspond best to their applications. ITU-T Rec. 0.181 (OY2002) vii ITU-T Recommendation 0.181 Equipment to assess error performance on STM-N interfaces 1 Scope This Recommendation specifies the functions of a measuring equi
34、pment capable of assessing SDH error performance at STM-N interfaces. ITU-T Rec. G.707 3 defines the STM-N signals applicable to these measurements. ITU-T Rec. G.703 i, G.957 lo and G.691 17 define the STM-N physical interface characteristics. Measurement modes and functions defined in this Recommen
35、dation enable: o any measuring equipment to analyze information provided by another measuring equipment any two measuring equipments to provide the same means to analyze the error performance (e.g. measurement modes and test sequences are common to all measuring equipment); of a given digital transm
36、ission path or path segment. o With regard to the numerous possibilities to make measurements on STM-N signals, a set of measurements modes are defined (see clause 5). Each measurement mode depends on the type of network entity under test, i.e. on the type of measured STM-N signal and on the type of
37、 SDH network elements crossed by the measured signal. In addition, the required functions of the Generator and Receiver part of the error performance measuring equipment are described below (see clauses 6 and 7). 2 References The following Recommendations and other references contain provision which
38、, 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; all users of this Recommendation are therefore encouraged to investigate the possibility of
39、 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 ITU-T Recommendation G.703 (200 i), Physical/electrical characteristics of hierarchical digital interfaces. ITU-T Recommen
40、dation G.706 (1991), Frame alignment and Cyclic Redundancy Check (CRC) procedures relating to basic fiame structures deflned in Recommendation G. 704. ITU-T Recommendation G.707N. 1322 (2000), Network node interface for the synchronous digital hierarchy. ITU-T Recommendation G.772 (1 993), Protected
41、 monitoring points provided on digital transmission systems. ITU-T Recommendation G.775 (1999, Loss of Signal (LUS), Alarm Indication Signal (AIS) and Remote Defect Indication (Ror) defect detection and clearance criteria for PDH signals . ITU-T Recommendation G.783 (2000), Characteristics of Synchr
42、onous Digital Hierarchy (SDH) equipment functional blocks. ITU-T Recommendation G.784 (1 999), Synchronous Digital Hierarchy (SDH) management. 6 7 ITU-T Rec. 0.181 (05/2002) 1 ITU-T Recommendation G.825 (2000), The control ofjitter and wander within digital networks which are based on the Synchronou
43、s Digital Hierarchy (SDH). ITU-T Recommendation G.826 (1 999), Error performance parameters and objectives for international, constant bit rate digital paths at or above the primary rate. ITU-T Recommendation G.957 (1 999), Optical interfaces for equipments and systems relating to the synchronous di
44、gital hierarchy. ITU-T Recommendation M.2 1 O 1 (2000), Performance limits and objectives for bringing- into-service and maintenance of international SDH paths and multiplex sections. ITU-T Recommendation O. 150 (1 996), General requirements for instrumentation for performance measurements on digita
45、l transmission equipment. ITU-T Recommendation 0.3 (1992), Climatic conditions and relevant tests for measuring equipment. ITU-T Recommendation V.24 (2000), List of definitions for interchange circuits between Data Terminal Equipment (DTE) and Data Circuit-terminating Equipment (DCE). ITU-T Recommen
46、dation V.28 (1 993), Electrical characteristics for unbalanced double-current interchange circuits. ITU-T Recommendation G.813 (1996), Timing characteristics of SDH equipment slave clocks (SEC). ITU-T Recommendation G.69 1 (2000), Optical interfaces for single-channel STM-64, STM-256 systems and oth
47、er SDH systems with optical ampliJiers. ITU-T Recommendation G. 806 (2000), Characteristics of transport equipment - Description methodology and generic jnctionality. ITU-T Recommendation G. 828 (2000), Error performance parameters and objectives for international, constant bit rate synchronous digi
48、tal paths. ITU-T Recommendation G.829 (2000), Error performance events for SDH multiplex and regenerator sections. Definitions This Recommendation defines the following terms: o Test Sequence Error (TSE): See Annex A. Test Signal Structure (TSS): See Annex C. o o End-to-End Transparency: See 5.3. 4
49、Abbreviations This Recommendation uses the following abbreviations. EUT Entity Under Test PDH Plesiochronous Digital Hierarchy SDH Synchronous Digital Hierarchy TSS Test Signal Structure See also 5.2.1 and Annex A for anomalies and defect abbreviations. 2 ITU-T Rec. 0.181 (05/2002) 5 This clause gives a list of the measurement modes which can be provided by one or more measuring equipments. Measurement modes and events to be monitored 5.1 Two sets of measurement modes are identified: 1) Out-of sewice measurement modes Definition of the measurement modes After setting u
