1、STD-ITU-T RECMN E-733-ENGL 1998 H q8b2591 Ob5bL14 8b7 m INTERNATIONAL TELECOMMUNICATION UNION ITUIT TELECOMMU N KATION STANDARDIZATION SECTOR OF ITU E.733 (I 1/98) SERIES E: OVERALL NETWORK OPERATION, TELEPHONE SERVICE, SERVICE OPERATION AND HUMAN FACTORS Quality of service, network management and t
2、raffic engineering - Traffic engineering - ISDN traffic engineering Methods for dimensioning resources in Signalling System No. 7 networks ITU-T Recommendation E.733 (Previously CCITT Recommendation) COPYRIGHT International Telecommunications Union/ITU TelecommunicationsLicensed by Information Handl
3、ing ServicesSTD-ITU-T RECMN E.733-ENGL 1998 YBb2591 Ob56115 7T3 I ITU-T E-SERIES RECOMMENDATIONS OVERALL NETWORK OPERATION, TELEPHONE SERVICE, SERVICE OPERATION AND HUMAN FACTORS ?PERATION, NUMBERING, ROUTING AND MOBILE SERVICES NTERNATIONAL OPERATION Definitions General provisions concerning Admini
4、strations General provisions concerning users Operation of international telephone services Numbering plan of the international telephone service International routing plan Tones in national signalling systems Maritime mobile service and public land mobile service 3PERATIONAL PROVISIONS RELATING TO
5、CHARGING AND ACCOUNTING IN THE INTERNATIONAL TELEPHONE SERVICE Charging in the international telephone service Measuring and recording call durations for accounting purposes UTILIZATION OF THE INTERNATIONAL TELEPHONE NETWORK FOR NON- TELEPHONY APPLICATIONS Ge ne ral Phototelegraphy ISDN PROVISIONS C
6、ONCERNING USERS QUALITY OF SERVICE, NETWORK MANAGEMENT AND TRAFFIC ENGINEERING NETWORK MANAGEMENT International service statistics International network management Checking the quality of the international telephone service TRAFFIC ENGINEERING Measurement and recording of traffic Forecasting of traf
7、fic Determination of the number of circuits in manual operation Determination of the number of circuits in automatic and semi-automatic operation Grade of service Definitions E. 1 OO-E. 103 E.104-E.119 E.120-E.139 E. 140-E. 159 E. 160-E. 169 E. 170-E. 179 E. 180-E. I99 E.200-E.229 E.230-E.249 E.260-
8、E.269 E.300-E.319 E.320-E.329 E.330-E.399 E.400-E.409 E.410-E.419 E.420-E.489 E.490-E. 505 E. 506-E. 509 E.510-E.519 E.520-E.539 E.540-E.599 E.600-E.699 ISDN traffic engineering E.700-E.749 Mobile network traffic engineering E.750-E.799 QUALITY OF TELECOMMUNICATION SERVICES: CONCEPTS, MODELS, OBJECT
9、IVES AND DEPENDABILITY PLANNING Terms and definitions related to the quality of telecommunication services Models for telecommunication services E.800-E.809 E. 8 1 O-E. 844 Objectives for quality of service and related concepts of telecommunication services Field data collection and evaluation on th
10、e performance of equipment, networks and services E.845-E.859 E.880-E.899 Use of quality of service objectives for planning of telecommunication networks E. 860-E. 879 For further details, please refer to ITU-T List of Recommendations. COPYRIGHT International Telecommunications Union/ITU Telecommuni
11、cationsLicensed by Information Handling ServicesITU-T RECOMMENDATION E.733 METHODS FOR DIMENSIONING RESOURCES IN SIGNALLING SYSTEM No. 7 NETWORKS Summary This Recommendation describes the methods for dimensioning resources in Signalling System No. 7 networks. It defines the reference traffic to be u
12、sed for dimensioning and then describes the dimensioning objectives and dimensioning methods for links and nodes in signalling networks. It considers methods for dimensioning signalling links and nodes in Signalling System No. 7 networks. Source ITU-T Recommendation E.733 was revised by ITU-T Study
13、Group 2 (1997-2000) and was approved under the WTSC Resolution No. 1 procedure on the 9“ of November 1998. Recommendation E.733 (11/98) 1 COPYRIGHT International Telecommunications Union/ITU TelecommunicationsLicensed by Information Handling ServicesSTD-ITU-T RECMN E.733-ENGL 1778 W 48b259L 0b5bLL7
14、57b b FOREWORD ITU (International Telecommunication Union) is the United Nations Specialized 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 ques
15、tions 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, establishes the topics for study by the ITU-T Study Groups which, in their turn, produce Recomm
16、endations 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 within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with IS0 and
17、IEC. NOTE In this Recommendation the term recognized operating agency (ROA) includes any individual, company, corporation or governmental organization that operates a public correspondence service. The terms Adminisbation, ROA and public correspondence are defined in the Constitution of the ITU (Gen
18、eva, 1992). 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 position concerning the evidence, validity or applicability of claimed Intelle
19、ctual 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, protected by patents, which may be required to implement this Recommendatio
20、n. 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 1999 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanic
21、al, including photocopying and microfilm, without permission in writing from the ITU. Recommendation E.733 (11/98) 11 COPYRIGHT International Telecommunications Union/ITU TelecommunicationsLicensed by Information Handling Services . - . STD-ITU-T RECMN E.733-ENGL 1998 M 48b2591 ObSb118 402 W CONTENT
22、S Page 1 2 3 4 5 6 7 7.1 7.2 7.3 8 8.1 8.2 8.3 8.4 9 Scope References Definitions Abbreviations . Introduction Reference traffic . Dimensioning objectives Signalling link dimensioning objectives 7.1.1 7.1 2 7.1.3 Criteria for determining pmax . Models used to determine queueing delays . Choosing bet
23、ween basic and PCR error correction . Node dimensioning . 7.2.2 Cross-office signalling delay . 7.2.4 Availability Value for pmax Signalling link dimensioning methods . 7.2.1 Capacity . 7.2.3 Signalling links Load calculation . Single link capacity Link set capacity . Dimensioning procedure Recommen
24、dation history Annex A . Analytic results comparing basic and PCR error correction . Recommendation E.733 (11/98) 1 1 2 3 3 4 5 5 7 8 9 10 10 10 11 11 11 11 11 11 12 12 12 . 111 COPYRIGHT International Telecommunications Union/ITU TelecommunicationsLicensed by Information Handling ServicesSTD*ITU-T
25、RECMN Ee733-ENGL 1996 Recommendation E.733 METHODS FOR DIMENSIONING RESOURCES IN SIGNALLING SYSTEM No. 7 NETWORKS (revised in 1998) 1 Scope This Recommendation considers methods for dimensioning signalling links and nodes in Signalling System No. 7 networks. Certain cases (e.g. due to new services)
26、involving segmentation of long messages or mixtures of very long and short messages require further study to give good approximations for signalling link dimensioning purposes. 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this t
27、ext, 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 applying the most recent edi
28、tion of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. - - - - ITU-T Recommendation E.492 (1 996), Traffic reference period. ITU-T Recommendation E.500 (1 998), Trafic intensiv measurement principles. CCITT Recommend
29、ation E.7 13 (1 992), Control plane traffic modelling. CCITT Recommendation E.721 (1991), Network grade of service parameters and target values for circuit-switched services in the evolving ISDN CCITT Recommendation E.723 (1 992), Grade-ofservice parameters for Signalling System No. 7 networks. ITU-
30、T Recommendation E.734 (1 996), Methods for allocating and dimensioning Intelligent Network (IN) resources. - ITU-T Recommendation 4.703 (1 996), Signalling link. - ITU-T Recommendation Q.706 (1 993), Message transfer part signalling performance. - ITU-T Recommendation Q.709 (1 993), Hypothetical si
31、gnalling reference connection. - ITU-T Recommendation Q.716 (1 993), Signalling Connection Control Part (SCCP) performance. ITU-T Recommendation 4.766 (1 993), Performance objectives in the integrated services digital network application. - - - 3 Definitions This Recommendation defines the following
32、 terms: 3.1 queueing delay: The queueing delay of a signalling message at the transmit queue of a signalling link is defined as the time from when the last bit of the message is placed in the transmit Recommendation E.733 (1 1/98) 1 COPYRIGHT International Telecommunications Union/ITU Telecommunicat
33、ionsLicensed by Information Handling Servicesbuffer until the first bit of the message is transmitted and the message is not subsequently retransmitted for level 2 error correction. Note that with this definition, in the case that a message is retransmitted one or more times for level 2 error correc
34、tion, the queueing delay includes the time it takes to wait for a successful transmission. 3.2 emission time: The emission time of a signalling message on a signalling link is the time it takes to place all the bits of the message onto the transmission media. The emission time is equal to the length
35、 of the message (octets) divided by the transmission speed (octetskec). 3.3 sojourn time: The sojourn time of a signalling message being sent over a signalling link is defined as the time from when the last bit of the message is placed into the transmit buffer until the last bit of the message is tr
36、ansmitted and the message is not subsequently retransmitted for level 2 error correction (i.e. the sum of queueing delay and emission time). The end-to-end sojourn time of a signalling message going over a path of signalling links and intermediate nodes is the time from when the last bit of the mess
37、age is placed in the transmit queue of the first signalling link in the path until the last bit of the message is received at the far end of the path and the message is correctly received (i.e. it does not fail the level 2 CRC error check). 3.4 propagation time: The propagation time of a correctly r
38、eceived signalling message over a signalling link is the time from when the first bit of the message is placed on the transmission media until the first bit of the message is placed in the receive buffer at the receiving end of the link. 4 Abbreviations This Recommendation uses the following abbrevi
39、ations: CRC DPP FISU GOS IN ISDN ISUP MSU MTP PCR POTS SCCP SLS SP STP TCAP TUP Cyclic Redundancy Check Daily Peak Period Fill-In Signal Unit Grade of Service Intelligent Network Integrated Services Digital Network ISDN User Part Message Signalling Unit Message Transfer Part Preventive Cyclic Retran
40、smission Plain Old Telephone Service Signalling Connection Control Part Signalling Lids Selection Signalling Point Signal Transfer Point Transaction Capabilities Application Part Telephone User Part 2 Recommendation E.733 (11198) COPYRIGHT International Telecommunications Union/ITU Telecommunication
41、sLicensed by Information Handling ServicesSTD-ITU-T RECMN E-733-ENGL 1998 R 48b259L Ob5bL2L TT? W 5 Introduction This Recommendation provides a methodology for the planning of Signalling System No. 7 networks, which may be used for circuit-related signalling e.g. to convey Telephone User Part (TUP)
42、and most ISDN User Part (ISUP) messages and non-circuit-related signalling e.g. to convey Transaction Capabilities Application Part (TCAP) messages. Fundamentally different methods are required from those used for planning circuit-switched telephone networks since Signalling System No. 7 is essentia
43、lly a delay system and the service times are much shorter, Clause 6 describes the reference traffic and reference period to be used to dimension the number of signalling links and to ensure that the capacity of network switching elements is not exceeded. The factors for determining a maximum design
44、link utilization, p, are given, which ensure that the end-to-end delay objectives described in Recommendation E.723 are met for the reference connection described therein. Initial values for p, being used are described. Methods are then given for determining the number of signalling links required a
45、nd the switching capacity required. It is important to note that the efficiency of signalling links should not be the primary consideration when planning signalling networks. The performance of the network under failure and traffic overload has greater significance than when planning circuit-switche
46、d telephone networks. 6 Reference traffic 6.1 This clause defines the reference traffic needed to give the basis for dimensioning of Signalling System No. 7 networks. This Recommendation is based on Recommendation E.500, which gives the basis for the measurements needed for the design of circuit-swi
47、tched networks. 6.2 The average traffic intensity is measured over time intervals called read-out periods (see Recommendation E.492). The length of the read-out period must be chosen so that acceptable estimates of traffic intensity are obtained. Specific considerations that must be made in choosing
48、 the read-out period are given in Recommendation ES00 and in 6.4 below. 6.3 The traffic intensity is measured continuously over a day for consecutive read-out periods. The highest intensity value for each day is retained. The recommended daily traffic intensity measurement method is the one develope
49、d in Recommendation E.492, and it is called the Daily Peak Period (DPP) method. In this method the traffic intensity is measured for consecutive read-out periods of each day, and the peak traffic intensity for the day is recorded. Possible variations of this traffic measurement method are discussed in Recommendation E.500. The reference traffic load for dimensioning is defined over a monthly time interval. A set of days is chosen (e.g. working days) that are approximately statistically homogeneous. The normal and high reference loads are deterrnined by the following steps: 1
