1、 - STD-ITU-T RECMN O*LSL-ENGL 2000 4862-591 Ob71784 91b W INTERNAT ONAL TELECOMMUN ITU=T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU CATION UNION 0.191 (02/00) SERIES O: SPECIFICATIONS OF MEASURING EQUIPMENT Equipment for the measurement of digital and a na log u e/d ig i ta I pa ram ete rs Equi
2、pment to measure the cell transfer performance of ATM connections ITU-T Recommendation 0.1 91 (Previously CCITT Recommendation) c I STD-ITU-T RECMN O-3SL-ENGL 2000 H 4862593 0673785 852 R ITU-T O-SERIES RECOMMENDATIONS SPECIFICATIONS OF MEASURING EQUIPMENT ir- Il General Maintenance access Automatic
3、 and semi-automatic measuring systems 0.1-0.9 0.1 0-0.1 9 0.20-0.39 II Eaubment for the measurement of analogue parameters 0.40-0.1 29 II - - For further details, please refr to ITU-T List of Recommendations. EQUIPMENT TO MEASURE THE CELL TRANSFER PERFORMANCE OF ATM CONNECTIONS Summary This Recommen
4、dation describes algorithms and processes for the out-of-service estimation of the ATM layer cell transfer performance by means of the network performance parameters defined in Recommendations 1.356 and 1.357. Further guidance is provided for in-service measurements and UPC/NPC function performance
5、measurements. Source ITU-T Recommendation 0.191 was revised by ITU-T Study Group 4 (1997-2000) and was approved under the WTSC Resolution No. 1 procedure on 4 February 2000. Keywords ATM Measuring Equipment (AME), Cell Delay Variation (CDV), Cell Error Ratio (CER), Cell Loss Ratio (CLR), Cell Transf
6、er Delay (CTD), Network Performance Parameters (NPP), Out-of-Service (OOS), Reference Load Model (UM), Test Cell Payload Format, Traffic Profiles, UPC/NPC performance. STD-ITU-T RECMN O-LSL-ENGL 2000 48b259L 0671787 625 FOREWORD ITU (International Telecommunication Union) is the United Nations Speci
7、alized Agency in the field of telecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent 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 telecommunicati
8、ons on a worldwide basis. The World Telecommunication Standardization Conference WTSC), which meets every four years, 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
9、is covered by the procedure laid down in WTSC Resolution No. 1. In some areas of information technology which fall within MU-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 concisenes
10、s to indicate both a telecommunication administration and a recognized operating agency. INTELLECTUAL, PROPERTY RIGHTS 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
11、position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by IT 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
12、, 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. o ITU 2000 All rights reserved. No part of this publication may
13、be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the ITU. 1 2 3 4 5 5.1 5.2 5.3 5.4 5.5 6 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 6.10 7 7.1 Scope References Terms and definitions . Abbreviations . M
14、easurement of network parameters . Measurement point location and measurement process . ATM reference events and outcomes (anomalies and defects) Physical layer reference events and outcomes (anomalies and defects) ATM network performance parameters . Measurement modes . Out-of-service measurement m
15、ode . Generation of traffic at the ATM layer . Test cell payload format . Revision O test cell payload format . Revision 1 test cell payload format . 6.2.1 6.2.2 Test traffic profiles . 6.3.1 Standard traffic generator 6.3.2 Enhanced traffic generator Background traffic OAM traffic Simulation of ano
16、malies and defects CLP flow measurements . Measurement process . 6.8.2 Outcome monitoring process 6.8.3 Availability monitoring and storage control process Network performance parameters calculation 6.9.1 Error-related network performance parameters 6.9.2 Availability-related network performance par
17、ameters 6.9.3 Delay-related network performance parameters . 6.8.1 Cell monitoring process UPC/NPC performance parameters In-service measurement mode Network performance parameters estimation . 7.1.1 Monitored cell flows . 7.1.2 Error-related network performance parameters Page 1 1 3 3 5 5 6 7 7 9 9
18、 10 10 10 13 14 15 16 21 21 22 22 24 25 28 30 34 34 35 37 42 44 44 44 48 8 8.1 8.2 8.3 8.4 9 9.1 9.2 9.3 10 10.1 10.2 STD-ITU-T RECMN O-LSL-ENGL 2000 4862543 Ob73789 i(TB 7 .i . 3 7.1.4 Availability-related network performance parameters Delay-related network performance parameters . Physical interf
19、aces of the AME . General interface characteristics and bit rates Specific generator interface characteristics Specific receiver interface characteristics Information available at physical interfaces . Miscellaneous functions . Event timestamping Output to recording devices Remote control . Operatin
20、g conditions Environmental condiQom . Behaviour in case ofpower failure . Annex A . Criteria for the detection of anomalies. defects and indications . Annex B . Measurement algorithms . hex C . Test cell payload scramblingldescrambling C . 1 Scrambling/descrambling . C.2 Scrambling and CRC Appendix
21、I . Examples of use of the different measuring modes . I . 1 Use of the out-of-service measurement mode 1.2 Use ofthe in-service measurement mode . 1.2.1 End-to-end test 1.2.2 Segment test 1.2.3 UPCNPC testing . Combined use of out-of-service and in-service measurement modes 1.3 e Page 50 50 52 52 5
22、3 54 54 54 55 55 55 55 55 55 55 57 59 59 59 60 60 61 61 62 63 64 STDaITU-T RECMN O-193-ENGL 2000 48b25L Ob73790 LLT H Introduction and background The requirements for the characteristics of the ATM measuring equipment (AME) described in this Recommendation must be adhered to in order to ensure that
23、the following objectives are met: Compatibility between test equipment produced by different manufacturers: any generation of ATM cells by the AME should be equivalent given the same control settings on different test equipment. Any analysis of ATM cell performance by the AME should provide the same
24、 results as different test equipment when provided with the same cell stream(s). Compatibility between test equipment and network equipment: any in-service measurement by the AME of network performance parameters and defects defined in Recommendations 1.356 and 1.610 should provide the same results
25、as nework equipment monitoring when provided with the same cell stream(s). Compatibility between out-of-service and in-service measurements: any out-of-service analysis by the AME of performance parameters and defects defined in Recommendations 1.356 and 1.610 should provide higher quality results (
26、in terms of accuracy and robustness) than in-service monitoring when applied to the equivalent network connection(s). While requirements are given for the AME, the realization of the equipment configuration is not covered and should be given careful consideration by the designer and user. In particu
27、lar, it is not required that all features listed below shall be provided in one piece of measuring equipment. Users may select those functions which correspond best to their applications. This revised version is the combination of Recommendation 0.191 as approved in April 1997, its Addendum 1, detai
28、ling the measurement of error-related and availability-related parameters, as approved in October 1997, and text covering the measurement of delay-related parameters and UPC/NPC performance developed and agreed since the approval of Addendum 1. Recommendation 0.191 EQUIPMENT TO MEASURE THE CELL TRAN
29、SFER PERFORMANCE OF ATM CONNECTIONS (revised in 2000) 1 Scope This Recommendation describes the functions which an equipment assessing the ATM layer cell transfer performance should fulfil. The measurement or estimation of the ATM adaptation layer performance is not addressed in this Recommendation.
30、 Techniques developed in this Recommendation enable the measurement of the cell transfer outcomes and associated network performance parameters defined in Recommendation 1.356 131. These parameters are the basis for the characterization of the ATM layer cell transfer performance. Availability decisi
31、ons used are those specified in Recommendation 1.357 141 and associated availability Parameters are measured. Some guidance on the measurement of the performance of UPC/NPC functions is also given. Semi-permanent VPCs or VCCs are considered. Currently developed techniques apply to non- tagging netwo
32、rks and ATM connections operated under DBR and SBR ATM Transfer Capabilities (ATCs) specified in Recommendation 1.371 16. It might be expected that the set of functions provided will be augmented in future in order to take account of switched connections, tagging networks and other ATCs. This Recomm
33、endation focuses on the measurement of error-, availability-, and delay-related parameters in the Out-Of-Service (00s) mode. It details the complete performance estimation processes, indicates particular and exceptional cases, and specifies actions to be taken in these cases. Network performance par
34、ameters can be monitored, in-service, by the OAM cell streams defined in Recommendation 1.610 21, using techniques developed in Recommendation 1.356 131 together with some guidance given in this Recommendation. Functions defined in this Recommendation enable ATM Measuring Equipment (AME) conforming
35、to this Recommendation to inter-operate and provide comparable results. 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 wer
36、e valid. All Recommendations and other references are subject to revision; all 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 Recomm
37、endations is regularly published. 11 2 3 4 CCITT Recommendation G.702 (1988), Digital hierarchy bit rates. ITU-T Recommendation G.703 (1 998), Physical/eZectrical characteristics of hierarchical digital interfaces. ITU-T Recommendation G.704 (1998), Synchronous fiame structures used at 1544, 6312, 2
38、048, 8448 and 44 736 kbith hierarchical levels. ITU-T Recommendation G.707 (1996), Network node interface for the synchronous digital hierarchy (SDH). 151 E61 c71 191 ci91 ITU-T Recommendation G.772 (1 993), Protected monitoring points provided on digital transmission systems. ITU-T Recommendation G
39、.804 (1 998), ATM cell mapping into plesiochronous digital hierarchy (PDH). ITU-T Recommendation G.823 (1993), The control of jitter and wander within digital networks which are based on the 2048 kbith hierarchy. ITU-T Recommendation G.824 (1993), The control of jitter and wander within digital netw
40、orks which are based on the 1544 kbit/s hierarchy. ITU-T Recommendation G.825 (1993), The control of jitter and wander within digital networks which are based on the synchronous digital hierarchy (SDH). ITU-T Recommendation G.832 (1998), Transport of SDH elements on PDH networks: Frame and multiplex
41、ing structures. ITU-T Recommendation G.957 (1 999), Optical interfaces for equipments and systems relating to the synchronous digital hierarchy. ITU-T Recommendation 1.353 (1996), Reference events for defining ISDN and B-ISDN performance parameters. ITU-T Recommendation 1.356 (1 996), B-ISDN ATM lay
42、er cell transfer pe$ormance. ITU-T Recommendation 1.357 (1 996), B-ISDN semi-permanent connection availability. ITU-T Recommendation 1.361 (1999), B-ISDN ATM Layer speczjcation. ITU-T Recommendation 1.371 (1996), Trafic control and congestion control in B-ISDN. ITU-T Recommendation 1.432.2 (1 999),
43、B-ISDN user-network inteface - Physical layer specifcation: 155 520 kbith and 622 080 kbith operation. ITU-T Recommendation 1.432.3 (1 999), B-ISDN user-network interface - Physical layer speciJication: 1544 kbith and 2048 kbith operation. ITU-T Recommendation 1.432.4 (1 999), B-ISDN user-network in
44、terface - Physical layer specijication: 51 840 kbith operation. ITU-T Recommendation 1.432.5 (1 997), B-ISDN user-network interface - Physical layer specijkation: 25 600 kbith operution. ITU-T Recommendation 1.61 O (1 999), B-ISDN operation and maintenance principles and functions. CCITT Recommendat
45、ion 0.3 (1 992), 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 Recommendation V.28 (1 993), Electrical characteri
46、stics for unbalanced double- current interchange circuits. ITU-T Recommendation X.25 (1 996), Inteface between data terminal equipment (DTE) and data circuit-terminating equipment (DCE) for terminals operating in the packet mode and connected to public data networks by dedicated circuit. IEC Publica
47、tion 60625 (1 993), Programmable measuring instruments - Interface system (hyte serial, bit parallel). EEE Standard 488.1 (1987), IEEE standard digital interface for programmable instrumentation. 3 Terms and definitions This Recommendation defines the following terms: 3.1 CLP = O: Cells that have th
48、e cell loss priority bit in the payload type indicator set to O. 3.2 CLP = 1 : Cells that have the cell loss priority bit in the payload type indicator set to 1. 3.3 CLP = O + 1: Cells that have the cell loss priority bit in the payload type indicator set to either O or 1. 3.4 CTD hit count: The num
49、ber of absolute CTD samples which exceed a programmable CTD threshold. 3.5 Fx FM: The OAM fault management flow at the Fx (x = 4 or 5) level as specified in Recommendation 1.610 21. 3.6 Fx PM: The OAM performance management flow at the Fx (x = 4 or 5) level as specified in Recommendation 1.610 21. 3.7 In-service: The in-service measurement mode makes use of the end user equipment or network elements OAM capabilities for estimating network performance parameters. The connection is available to the end user who is transmitting their own
