1、I NTE RNATI ON AL TE L ECO M M U N I CATI ON U N I ON ITU-T TELECOMMUNICATION STAN DARD IZATION SECTOR OF ITU G.828 (03/2000) SERIES G: TRANSMISSION SYSTEMS AND MEDIA: DIGITAL SYSTEMS AND NETWORKS Digital transmission systems - Digital networks - Qual and availability targets t Y Error performance p
2、arameters and objectives for international, constant bit rate synchronous digital paths I TU -T Recom menda t ion G .828 (Formerly CCITT Recommendation) STDSITU-T RECMN G.828-ENGL 2000 4862593 0688396 243 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INT
3、ERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS GENERAL CHARACTERISTICS COMMON TO ALL ANALOGUE CARRIER- TRANSMISSION SYSTEMS G. 100-G.199 G.200-G.299 INDIVIDUAL CHARACTENSTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LINES G.300-G.399 GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELE
4、PHONE METALLIC LINES COORDINATION OF RADIOTELEPHONY AND LME TELEPHONY G.450-G.499 TERMINAL EQUIPMENTS G.70M.799 DIGITAL NETWORKS G.800-G.899 General aspects G.800-G.809 Design objectives for digital networks G.810-G.819 G.83-G.839 G.400-G.449 SYSTEMS ON RADIO-RELAY OR SATELLITE LrlJKS AND INTERCONNE
5、CTION WITH SDH network characteristics Management of transport network SDH radio and satellite systems integration Optical transport networks DIGITAL SECTIONS AND DIGITAL LINE SYSTEM G.840-G ,849 G.XSM.859 G.86O-G.869 G.8704.879 G.900-G.999 For further details, please refer to the list of ITU-T Reco
6、mmendations. STD=ITU-T RECMN G-828-ENGL 2000 48b2591 0688397 LBT ITU-T Recommendation G.828 Error performance parameters and objectives for international, constant bit rate synchronous digital paths Summary This Recommendation defines error performance parameters and objectives for international syn
7、chronous digital paths. While this Recommendation specifically addresses objectives for international digital paths, the allocation principles can be applied to the design of error performance for national or private synchronous digital paths. The objectives given are independent of the physical net
8、work supporting the path. This Recommendation is based upon a block-based measurement concept using error detection codes inherent to the path under test; the block repetition rate being in accordance with SDH technology. This simplifies in-service measurements. The events, parameters and objectives
9、 are defined accordingly. In addition to path performance assessment, tandem connection monitoring is covered. It is not required to apply this Recommendation to SDH paths using equipment designed prior to the date of adoption of this version of ITU-T Recommendation G.828 (March 2000). Source ITU-T
10、Recommendation G.828 was prepared by ITU-T Study Group 13 (1997-2000) and approved under the WTSC Resolution 1 procedure on 10 March 2000. Keywords Background Block Error (BBE), block-based concept, Error Detection Codes (EDC), error performance objectives, error performance parameters, Errored Seco
11、nd (ES), In-Service Measurements (ISM), Severely Errored Period (SEP), Severely Errored Second (SES), synchronous digital path, Tandem Connection Monitoring (TCM). STD*ITU-T RECMN Gm828-ENGL 2000 48b2571 Ob88398 Olb FOREWORD The International Telecommunication Union (ITLJ) is the United Nations spec
12、ialized 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 view to standardizing telecommunications on
13、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 turn, produce Recommendations on these topic s. The approval of ITU-T Recommendations is covered by the procedure laid
14、down in WTSC Resolution 1. In some areas of information technology which fall within ITU-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 telecommunicati
15、on administration and a recognized operating agency. INTELLECTUAL 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
16、 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, ITU had not received notice of intellectual property, protected by patents, which may be required to
17、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 2001 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any m
18、eans, electronic or mechanical, including photocopying and microfilm, without permission in writing from the ITU. 1 1.1 1.2 1.3 2 3 3.1 3.2 4 4.1 4.2 5 6 6.1 6.2 STD-ITU-T RECMN G-BZB-ENGL 2000 W 4862593 0688399 T52 CONTENTS Scope Application of this Recommendation . Transport network layers 1.2.1 S
19、DH transport networks 1.2.2 ATM connections Allocation of end-to-end performance . References Definitions and abbreviations . Abbreviations . Terms and Definitions 3.2.4 Error performance events 3.2.5 Error performance parameters . 3.2.6 Additional error performance event / performance parameter Mea
20、surement ofthe block In-service monitoring . Out-of-service measurements . Performance monitoring at the near end and far end of a path . Error performance objectives . End-to-end objectives . Apportionment of end-to-end objectives Allocation to the national portion of the end-to-end path . 6.2.1 6.
21、2.2 Allocation to the international portion of the end-to-end path Annex A . Criteria for entry to and exit from the unavailable state . Criterion for a bidirectional path Consequences on error performance measurements parameters . B.l. 1 Converting BIP measurements into errored blocks . B . 1.2 Blo
22、ck size for monitoring SDH paths . B.1.3 Anomalies A.l A.2 A.3 A.4 Annex B - Relationship between path performance monitoring and the block-based B.l General . Cntena for a single direction Criterion for a unidirectional path m Page 1 1 2 2 2 3 3 3 3 5 5 5 6 6 6 6 6 7 7 8 9 9 10 10 10 11 11 11 11 11
23、 11 12 STD-ITU-T RECMN G.828-ENGL 2000 4862573 Ob88400 5TLt B.1.4 Defects . Estimation of the performance parameters . B.2 B.3 Estimation of performance events at the far end of a path . Appendix I . Flow chart illustrating the recognition of anomalies . Appendix II . Applicability of ITU-T Recommen
24、dation G.828 to non-public networks . Page 12 13 14 14 17 STD-ITU-T RECMN G.828-ENGL 2000 486259l1 Ob88401 430 m ITU-T Recommendation G.828 Error performance parameters and objectives for international, constant bit rate synchronous digital paths 1 Scope This Recommendation specifies error performan
25、ce events, parameters and objectives for synchronous digital paths. Subclauses 1.1 to 1.3 give further details. 1.1 Application of this Recommendation This Recommendation is applicable to international, constant bit rate digital paths based on Synchronous Digital Hierarchies. While this Recommendati
26、on specifically addresses objectives for intemational digital paths, the allocation principles can be applied to the design of error performance for national or private synchronous digital paths. This Recommendation is generic in that it defines the parameters and objectives for paths independent of
27、 the physical transport network providing the paths. Compliance with the performance specification of this Recommendation will, in most cases, also ensure that subtending connections Will meet the requirements laid out in ITU-T Recommendations G.821 (N x 64 kbit/s) 5 and G.826 6. Therefore, this Rec
28、ommendation is the only Recommendation required for designing the error performance of synchronous digital paths (see Note). In accordance with the definition of a digital path, path end points may be located at users premises. NOTE - It is not required to apply this Recommendation to SDH paths usin
29、g equipment designed prior to the adoption of this Recommendation in March 2000. Performance events and objectives for paths using equipment designed prior to this date are given in ITU-T G.826. Paths are used to support services such as circuit switched, packet switched and leased circuit services.
30、 The quality of such services, as well as the performance of the network elements belonging to the service layer, is outside of the scope of this Recommendation. However, G.828-based paths can carry ATM traffic. Synchronous digital paths meeting the objectives of this Recommendation will enable the
31、ATM traffic to meet 1.356 9. The error performance objectives are applicable to each direction of the path independently. The values apply end-to-end over a 27 500 km Hypothetical Reference Path (see Figure 3) which may include optical fibre, digital radio relay, metallic cable and satellite transmi
32、ssion systems. The performance of multiplex and cross-connect functions employing ATM techniques is not included in these values. The parameter definitions are block-based with the block repetition rate in accordance with SDH technology, making in-service measurement convenient. In addition to in-se
33、rvice measurements, compliance with this Recommendation can be assessed using out-of-service measurements or estimated by measures compatible with this Recommendation as those specified in Annex B. The objectives given in this Recommendation are long-term objectives to be met over an evaluation peri
34、od of typically 30 consecutive days (one month). Shorter measurement periods required for maintenance and bringing-into-service are covered in ITU-T Recommendation M.2101 1 O. STDITU-T RECMN G-E-ENGL io00 LZSW, OMMOZ 377 m 1.2 Transport network layers This Recommendation specifies the error performa
35、nce of synchronous digital paths in a given transport network layer. Two cases are considered: 1) 2) See 1.2.1 and 1.2.2 for details. NOTE - For the purpose of this Recommendation, SDH transport includes other SDH type systems such as the Synchronous Optical Network (SONET). End-to-end Synchronous D
36、igital Hierarchy (SDH) transport. SDH paths forming the physical layer portions of ATM connections. 1.2.1 SDH transport networks In the context of this Recommendation, an SDH digital path is a trail carrying an SDH payload and associated overhead through the layered transport network between the pat
37、h terminating equipment (see Figure 1). ITU-T Recommendation M.2101 lo provides Bringing into-Service (BIS) and maintenance requirements which ensure that G.828 objectives are met. Application of ITU-T Recommendation G.828 4 b SDH Path Layer Network T1316620-94 NOTE - A and B are path end points loc
38、ated at the terminations as defined in ITU-T Recommendation G.783 2. Figure 1lG.828 - Application of ITU-T Recommendation G.828 for an end-to-end SDH path 1.2.2 ATM connections Where the path forms the physical part of an ATM connection (see Figure 2), the overall end-to-end performance of the ATM c
39、onnection is defined by ITU-T Recommendation 1.356 9. In this case, this Recommendation can be applied with an appropriate allocation to the performance between the path end points terminated by the physical layer of ATM cross-connects or switches (see Recommendation 1.321 8). ATM transmission paths
40、 in the physical layer correspond to a stream of cells mapped into SDH frame structures. ITU-T Recommendation 1.356 ATM ATM SDH TU-T Recommendation G.828 SDH SDH U-T Recommendation G.828 SDH T1316-95 AAL ATM Adapatation Layer ATM ATMLayer SDH SDHLayer Figure 2/G.828 - Architectural relationship betw
41、een ITU-T Recommendations G.828 and 1.356 9 STD.1TU-T RECflN G.BZB-ENGL 2000 SB 4Bh2571 abaBYn3 203 1.3 Allocation of end-to-end perforrriance Allocations of end-to-end perforrnancc of synchronous digital paths are deri ed using the rules laiu out in 6 2, which are length and complexity based. Detai
42、led allocations cf (i 82b performance to the individual components (lines, sections. multiplexers and cross-connects etc.) are outside the scope of this Recornmendation, but when such allocations are performed, the requirements of 6.2 vith regard to national and intemational allocations should be me
43、t. 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 Recommendations and other references are subject to revi
44、sion; 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 Recommendations is regularly published. ITU-T Recommendation G.707 ( 1996),
45、 Network node interface -for the synchronous digital hierarchy (SDH). ITU-T Recommendation G.783 (I 997), Characteristics of synchronous digital hierarch) (SOH, eg u ipm en t fun ctiona 1 blocks. ITU-T Recommendation G.784 (1 999), Synchronous digital hierarchy (SOH) management. ITU-T Recommendation
46、 G.803 (2000), Architecture of transport networks based on the synchronous digital hierarchy (SDH). ITU-T Recommendation G.821 (1 996), Error performance of an international digital connection operuting at u bit rate below the primary rute and forming part of an integrated services digital network.
47、ITU-T Recommendation G.826 ( 1 999), Error performance parnmeters and objectives for inernational, constant bit rate digital paths at or above the primury rute. ITU-T Recommendation G.827 (ZOOO), Availability parumeters and objectives for path elements of international constant bit rate digital path
48、s at or above the primary rate. CCITT Recommendation 1.321 (I 991), R-ISDN Protocol reference model and its application. ITU-T Recommendation 1.356 (2000), B-ISDN ATM Zayer cell transfer performance. ITU-T Recommendation M.2 I O 1 (2000), Performance limits for bringing-into-sewice nnrl maintenance
49、of international SDHpaths and multiplex sections. Definitions and abbreviations Abbreviations This Recornmendation uses the following abbreviations: AAL ATM Adaptation Layer AIS Alami Indication Sipal ATM Asynchronous Transfer Mode AU Administrative Unit BBE Background Block Error BBER BIP 3-ISDN CBR CSES EB EDC ES ESR HP HPTC HFW IG ISDN ISM LOF LOM LOP LOS LP LPTC LTC N-ISDN 00s PEP PLM RDI REI RS SDH SEP SEP1 SES SESR SONET STM SWQ Background Block Error Ratio Bit Interleaved Parity Broadband ISDN Constant Bit Rate Consecutive Severely Errored Se
