1、 INTERNATIONAL TELECOMMUNICATION UNION ITU-T E.438TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (03/2000) SERIES E: OVERALL NETWORK OPERATION, TELEPHONE SERVICE, SERVICE OPERATION AND HUMAN FACTORS Quality of service, network management and traffic engineering Network management Checking the quali
2、ty of the international telephone service Performance parameters and measurement methods to assess N-ISDN 64 kbit/s circuit-switched bearer service UDI in operation ITU-T Recommendation E.438 (Formerly CCITT Recommendation) ITU-T E-SERIES RECOMMENDATIONS OVERALL NETWORK OPERATION, TELEPHONE SERVICE,
3、 SERVICE OPERATION AND HUMAN FACTORS For further details, please refer to the list of ITU-T Recommendations.OPERATION, NUMBERING, ROUTING AND MOBILE SERVICES INTERNATIONAL OPERATION Definitions E.100E.103 General provisions concerning Administrations E.104E.119 General provisions concerning users E.
4、120E.139 Operation of international telephone services E.140E.159 Numbering plan of the international telephone service E.160E.169 International routing plan E.170E.179 Tones in national signalling systems E.180E.189 Numbering plan of the international telephone service E.190E.199 Maritime mobile se
5、rvice and public land mobile service E.200E.229 OPERATIONAL PROVISIONS RELATING TO CHARGING AND ACCOUNTING IN THE INTERNATIONAL TELEPHONE SERVICE Charging in the international telephone service E.230E.249 Measuring and recording call durations for accounting purposes E.260E.269 UTILIZATION OF THE IN
6、TERNATIONAL TELEPHONE NETWORK FOR NON-TELEPHONY APPLICATIONS General E.300E.319 Phototelegraphy E.320E.329 ISDN PROVISIONS CONCERNING USERS International routing plan E.350E.399 QUALITY OF SERVICE, NETWORK MANAGEMENT AND TRAFFIC ENGINEERING NETWORK MANAGEMENT International service statistics E.400E.
7、409 International network management E.410E.419 Checking the quality of the international telephone service E.420E.489 TRAFFIC ENGINEERING Measurement and recording of traffic E.490E.505 Forecasting of traffic E.506E.509 Determination of the number of circuits in manual operation E.510E.519 Determin
8、ation of the number of circuits in automatic and semi-automatic operation E.520E.539 Grade of service E.540E.599 Definitions E.600E.699 ISDN traffic engineering E.700E.749 Mobile network traffic engineering E.750E.799 QUALITY OF TELECOMMUNICATION SERVICES: CONCEPTS, MODELS, OBJECTIVES AND DEPENDABIL
9、ITY PLANNING Terms and definitions related to the quality of telecommunication services E.800E.809 Models for telecommunication services E.810E.844 Objectives for quality of service and related concepts of telecommunication services E.845E.859 Use of quality of service objectives for planning of tel
10、ecommunication networks E.860E.879 Field data collection and evaluation on the performance of equipment, networks and services E.880E.899 Recommendation E.438 (03/2000) i ITU-T RECOMMENDATION E.438 PERFORMANCE PARAMETERS AND MEASUREMENT METHODS TO ASSESS N-ISDN 64 kbit/s CIRCUIT-SWITCHED BEARER SERV
11、ICE UDI IN OPERATION Summary This Recommendation presents an overview of performance parameters for the measurement and assessment of N-ISDN 64 kbit/s circuit switched UDI bearer services in operation. Guidelines and considerations for measurement methods are also provided. These parameters can be u
12、sed for N-ISDN monitoring and improvement in operations. Their achieved values can be used both to establish guaranteed performance levels in Service Level Agreement with the customers and Service Quality Agreement with other administrations, and to verify, analyse and improve the performance level
13、currently offered. Source ITU-T Recommendation E.438 was prepared by ITU-T Study Group 2 (1997-2000) and was approved under the WTSC Resolution No. 1 procedure on 13 March 2000. ii Recommendation E.438 (03/2000) FOREWORD ITU (International Telecommunication Union) is the United Nations Specialized A
14、gency 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 telecommunications on a
15、 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 is cove
16、red by the procedure laid down in WTSC Resolution No. 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 conciseness to i
17、ndicate 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 positio
18、n concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by 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, prot
19、ected 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. Ge3 ITU 2001 All rights reserved. No part of this publication may be r
20、eproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the ITU. Recommendation E.438 (03/2000) iii CONTENTS Page 1 Introduction. 1 2 Scope. 1 3 References. 2 4 Terms and definitions . 3 5 Abbreviations and
21、 acronyms. 4 6 ISDN CSCT NP/QOS parameters 4 7 Measurement methods for ISDN CSCT NP/QOS parameters 5 7.1 Measurement methods applicable. 6 7.2 Comparison of three measurement methods in terms of measurable performance parameter. 6 7.3 Characteristics of each measurement method. 7 7.3.1 Test call bas
22、ed measurement . 7 7.3.2 CDR based measurement. 7 7.3.3 INMD based measurement 7 iv Recommendation E.438 (03/2000) Introduction ISDN traffic is growing because it allows faster access to and use of advanced services (such as Internet access, videocommunication, etc.) than traditional PSTN networks.
23、ISDN networks are completely defined by ITU-T in terms of architecture, features, access interfaces, transport and signalling protocols, interworking functionality and basic and supplementary services. Recommendation E.721 gives good guidance for planning and designing ISDN networks with adequate GO
24、S levels. Recommendation M.3650 covers maintenance performance related aspects of ISDN. Operations related ISDN NP/QOS aspects, however, are spread among many specific ITU-T Recommendations, some of which only partially cover performance parameters, events and methods for their measurement. This Rec
25、ommendation attempts to give a complete and organic overview of ISDN NP/QOS parameters and related measurement methods to be used in operations for monitoring and improvement purposes. The measures, identified according to the methodological approach described in ITU-T Recommendations I.350 6 and E.
26、820 4, are defined in clause 6. Additional definitions are given in clause 4. The ISDN NP/QOS parameters can be collected and measured by Administrations in accordance with the measurement methods described in clause 7. Recommendation E.438 (03/2000) 1 Recommendation E.438 PERFORMANCE PARAMETERS AND
27、 MEASUREMENT METHODS TO ASSESS N-ISDN 64 kbit/s CIRCUIT-SWITCHED BEARER SERVICE UDI IN OPERATION (Geneva, 2000) 1 Introduction ISDN traffic is growing because it allows faster access to and use of advanced services (such as Internet access, videocommunication, etc.) than traditional PSTN networks. I
28、SDN networks are completely defined by ITU-T in terms of architecture, features, access interfaces, transport and signalling protocols, interworking functionality and basic and supplementary services. Recommendation E.721 gives good guidance for planning and designing ISDN networks with adequate GOS
29、 levels. Recommendation M.3650 covers maintenance performance related aspects of ISDN. Operations related ISDN NP/QOS aspects, however, are spread among many specific ITU Recommendations, some of which only partially cover performance parameters, events and methods for their measurement. This Recomm
30、endation attempts to give a complete and organic overview of ISDN NP/QOS parameters and related measurements methods to be used in operations for monitoring and improvement purposes. The measures, identified according to the methodological approach described in ITU-T Recommendations I.350 6 and E.82
31、0 4, are defined in clause 6 of this Recommendation Additional definitions are given in clause 4. The ISDN NP/QOS parameters can be collected and measured by administrations in accordance with the measurement methods described in clause 7. 2 Scope The main aim of this Recommendation is to give compl
32、ete guidance for the characterization and assessment, in operation, of the performance of bearer CSCT 64 kbit/s UDI ISDN services by a set of operational NP/QOS measures, related to all the main functions/phases of an ISDN call (setup, information transfer, release). The values measured for these pa
33、rameters are mainly used for Operation, but also for Administration and Maintenance (OAM) purposes, and for managing Service Level Agreements (SLAs) and Service Quality Agreements (SQAs) 21 with customers and other ROAs. To pursue this aim, this Recommendation: identifies the main ISDN NP/QOS parame
34、ters for assessing the serveability and integrity of 64 kbit/s based circuit switched ISDN connections and networks. References to E-, G-, I-, M-, O-, P- and Q-series Recommendations for NP/QOS parameters definition are provided. Measures are related both to single B-channel and multi B-channel appl
35、ications using both BRA and PRA accesses. relates these NP/QOS parameters to test call based, CDR-based and INMD-based measurement methods for assessing the connection setup, information transfer and disengagement phases of an ISDN call. Measurability considerations for these ISDN NP/QOS parameters,
36、 depending on the measurement method used, are given. The most of the ISDN performance parameters identified are similar to those already made and used in operation for PSTN. This allows a set of homogeneous measures particularly useful in the case of mixed ISDN PSTN connections or for comparisons o
37、f services between ISDN and PSTN 2 Recommendation E.438 (03/2000) connections in terms of performance values achieved. However, some performance parameters have been added or modified1to those related to PSTN because: ISDN connections, up to the network access point (and sometimes up to the service
38、access point) are fully digital. Many services/applications can share the same connection(s). A single service/application communication2can involve more than one B-channel/connection. A communication request can be performed both by en bloc and by overlap sending. New communication control function
39、s, in addition to those related to the basic telephone call, such as bearer control, compatibility checking, terminal selection, supplementary services control, notify, etc., may be present. Routing can depend on the kind of the bearer service chosen on a per call basis. Measurement can be made at s
40、tandard user/network interfaces, using enhanced signalling protocols (e.g. DSS1, SS7 etc.). The assessment of some NP/QOS parameters can also require measurement on B- (information transfer) channels in addition to those taken on D- (signalling) channel. This Recommendation does not set performance
41、planning objectives these are mainly defined in 5 but rather describes means by which actual NP can be assessed. The mapping of the measurement made with this Recommendation into parameters reflecting customer opinion is beyond the scope of this Recommendation and is left to the individual ROA. 3 Re
42、ferences 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 revision; a
43、ll 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. 1 ITU-T Recommendation I.112 (1993), Vocab
44、ulary of terms for ISDNs. 2 ITU-T Recommendation E.600 (1993), Terms and definitions of traffic engineering. 3 ITU-T Recommendation E.800 (1994), Terms and definitions related to quality of service and network performance including dependability. 4 ITU-T Recommendation E.820 (1992), Call models for
45、serveability and service integrity performance. 5 ITU-T Recommendation E.721 (1999), Network grade of service parameters and target values for circuit-switched services in the evolving ISDN. 6 ITU-T Recommendation I.350 (1993), General aspects of quality of service and network performance in digital
46、 networks, including ISDNs. _ 1Also some related objective values should be modified according to the media (voice, data, video) or the teleservice used in the call, even if they are not included in this Recommendation. 2With the term call, according to the ITU-T Recommendation E.600 2, we intend a
47、teleservice/application request that can involve in case of multi-channel call more than one bearer service/ network connection. For simplicity, we consider here multi-channel teleservices/applications using only 64 kbit/s UDI bearer service. Recommendation E.438 (03/2000) 3 7 ITU-T Recommendation I
48、.352 (1993), Network performance objectives for connection processing delays in an ISDN. 8 ITU-T Recommendation I.353 (1996), Reference events for defining ISDN and B-ISDN performance parameters. 9 ITU-T Recommendation I.355 (1995), ISDN 64 kbit/s connection type availability performance. 10 ITU-T R
49、ecommendation G.114 (1988), Mean one-way propagation time. 11 ITU-T Recommendation G.821 (1996), Error performance of an international digital connection operating at a bit rate below the primary rate and forming part of an integrated services digital network. 12 ITU-T Recommendation O.152 (1992), Error performance measuring equipment for bit rates of 64 kbit/s and N 64 kbit/s. 13 ITU-T Recommendation E.846 (1993), Accessibility for 64 kbit/s circuit-switched internati
