1、INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU E.760 (03/2000) SERIES E: OVERALL NETWORK OPERATION, TELEPHONE SERVICE, SERVICE OPERATION AND HUMAN FACTORS Quality of service, network management and traffic engineering - Traffic engineering - Mobile networ
2、k traffic engineering Terminal mobility traffic modelling ITU-T Recommendation E.760 (Formerly CCITT Recommendation) ITU-T E-SERIES RECOMMENDATIONS OVERALL NETWORK OPERATION, TELEPHONE SERVICE, SERVICE OPERATION AND HUMAN FACTORS OPERA TION, NUMBERING, ROUTING AND MOBILE SERVICES INTERNATIONAL OPERA
3、TION Definitions General provisions concerning Administrations General provisions concerning users Operation of international telephone services Numbering plan of the international telephone service International routing plan Tones in national signalling systems Numbering plan of the international t
4、elephone service Maritime mobile service and public land mobile service OPERATIONAL PROVISIONS RELATING TO 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
5、INTERNATIONAL TELEPHONE NETWORK FOR NON- TE LEP H ONY AP PLI CATI ONS General Phototelegraphy International routing plan QUALITY OF SERVICE, NETWORK MANAGEMENT AND TRAFFIC ENGINEERING NETWORK MANAGEMENT ISDN PROVISIONS CONCERNING USERS International service statistics International network managemen
6、t Checking the quality of the international telephone service TRAFFIC ENGINEERING Measurement and recording of traffic Forecasting of traffic Determination of the number of circuits in manual operation Determination of the number of circuits in automatic and semi-automatic operation Grade of service
7、 Definitions ISDN traffic engineering Mobile network traffic engineering QUALITY OF TELECOMMUNICATION SERVICES: CONCEPTS, MODELS, OBJECTIVES AND DEPENDABILITY PLANNING Terms and definitions related to the quality of telecommunication services Models for telecommunication services Objectives for qual
8、ity of service and related concepts of telecommunication services Use of quality of service objectives for planning of telecommunication networks Field data collection and evaluation on the performance of equipment, networks and services E. 1 00-E. 103 E.104-E.119 E. 120-E. 139 E. 140-E. 159 E. 160-
9、E. 169 E. 170-E. 179 E. 180-E. 189 E. 190-E. 199 E.200-E.229 E.230-E.249 E.260-E.269 E.300-E.319 E.320-E.329 E.350-E.399 E.400-E.409 E.41 0-E.419 E.420-E.489 E.490-E.505 E.506-E509 E.510-E519 E.520-E539 E.540-E599 E.600-E.699 E.700-E.749 E.800-E.809 E.810-E.844 E.845-E.859 E.860-E.879 E.880-E.899 Fo
10、r further details, please rer to the list of ITD-T Recommendations. ITU-T RECOMMENDATION E.760 TERMINAL MOBILITY TRAFFIC MODELLING Summary Terminal mobility traffic modelling for land terrestrial or satellite-based mobile systems (including cellular, cordless, paging and IMT-2000) presented in this
11、Recommendation is intended to characterize the mobile user traffic demand associated with mobile services. This demand has significance for both the user and the signalling plane. Source ITU-T Recommendation E.760 was prepared by ITU-T Study Group 2 (1997-2000) and was approved under the WTSC Resolu
12、tion No. 1 procedure on 13 March 2000. Recommendation E.760 (03/2000) 1 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-
13、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 Conference (WTSC), which meets every four years, establishes the topics for st
14、udy 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 covered by the procedure laid down in WTSC Resolution No. 1. In some areas of information technology which fall within ITU-Ts purview, the neces
15、sary 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 telecommunication administration and a recognized operating agency. INTELLECTUAL PROPERTY RIGHTS The ITU draws attention to t
16、he 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 Intellectual Property Rights, whether asserted by ITU members or others outs
17、ide 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 Recommendation. However, implementors are cautioned that this may not represent th
18、e 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 be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writi
19、ng fi-om the ITU. 11 Recommendation E.760 (03/2000) CONTENTS 1 2 3 4 5 6 6.1 6.2 6.3 7 8 Objective and scope Related Recommendations . Definitions Abbreviations Introduction . Estimation of traffic demand for cellular networks Rationale . Methodology . Upgrading of the procedure for estimating the t
20、raffic demand . Mobility modelling and impact on signalling traffic History . Appendix I . Estimating the traffic demand Appendix II . An example methodology for modelling the handover rate between cells in Appendix III . An example methodology for modelling the location registration and cellular, t
21、errestrial-based mobile systems . location updating rate in cellular, terrestrial-based mobile systems . Page 1 2 2 3 3 4 4 5 6 6 6 7 9 12 . Recommendation E.760 (03/2000) 111 Recommendation E.760 TERMINAL MOBILITY TRAFFIC MODELLING (Geneva, 2000) 1 Objective and scope 1.1 Terminal mobility traffic
22、modelling for land terrestrial or satellite-based mobile systems (including cellular, cordless, paging and IMT-2000) presented in this Recommendation is intended to characterize the mobile user traffic demand associated with mobile services. This demand has significance for both the user and the sig
23、nalling plane. 1.2 The geographical scope of traffic demand and terminal mobility modelling ranges from metropolitan to international areas. As an example, Figure 1 shows the scope of Recommendation E.760 for the case of terrestrial-based cellular networks under the assumption of separated fixed and
24、 mobile networks (see Recommendation E.75 1). The figwe indicates two teletraffic interfaces at which traffic demand has to be characterized for traffic engineering purposes. One traffic demand relates to the radio interface; the other is associated with the characterization of mobile related traffi
25、c which insists on the fixed network. This latter characterization is intended for the purposes of dimensioning fixed network resources used for supporting mobile services. NOTE - The figure shows the interconnection of (separated) fiied and mobile networks, Recommendation E.220, and the allocation
26、of mobility management functions (MMF) within the mobile network, as is typically the case with second generation mobile systems (e.g. GSM). Depending on the actual implementations and traEc requirements, the MSC (Mobile Switching Centre) can be connected with the fixed network ant the LE (Local Exc
27、hange) or TE (Terminal Exchange) level. This is succinctly indicated through the combination LE/TE. In fact, the allocation of MMF has a range of possible options including the arrangements resulting from integrated mobile and fied network, Recommendation E.75 1. Figure 1E.760 - Scope of traffic dem
28、and characterization for cellular networks (separated mobile and fixed network, mobile-to-mobile communication) Recommendation E.760 (032000) 1 1.3 This Recommendation addresses traffic demand modelling related to land mobile systems and traffic demand associated with the radio interface. Modelling
29、of traffic demand insisting on the fixed network is for further study. Finally, traffic modelling for other systems, e.g. cordless and paging systems, is also for further study. 2 Related Recommendations The following Recommendations contain material that is either relevant to or provides background
30、 for this Recommendation. - - CCITT Recommendation E.201 (199 i), Reference Recommendation for mobile services. CCITT Recommendation E.202 ( 1992), Network operational principles forfiture public mobile systems and services. ITU-T Recommendation E.220 (1 996), Interconnection ofpublic land mobile ne
31、tworks ITU-T Recommendation E.600 (1993), Terms and definitions of trafic engineering. CCITT Recommendation E.7 1 1 (1 992), User demand modelling. CCITT Recommendation E.7 12 (1 992), User plane trafic modelling. CCITT Recommendation E.7 13 (1 992), Control plane trafic modelling. ITU-T Recommendat
32、ion E.75 1 (1 996), Reference connections for trafic engineering of land mobile networks. ITU-T Recommendation E.77 1 (1 996), Network grade of service parameters and target values for circuit switched land mobile services. ITU-T Recommendation E.773 (1996), Maritime and aeronautical mobile grade of
33、 service concept. PLM-N). - ITU-T Recommendation F. 1 15 (1995), Service objectives andprinciples for future public land mobile telecommunication systems. ITU-R Recommendation M. 1034- 1 (1 997), Requirements for the radio inteflace(s) for International Mobile Telecommunications-2000 (IMT-2000). - 3
34、 Definitions 3.1 E.75 1 and E.77 1 will be applicable. Additional definitions used in this Recommendation are as follows: 3.1.1 Network attachment point: The physical location in the network used for terminating the routing of calls to/fiom the end-user system (terminal identifier). In the case wher
35、e the segment spanned between the physical termination of the end-user system and the network access point has additional functions to the sheer electrical connection, access network functionality is required for user information and signalling transfer. For the purposes of this Recommendation, defi
36、nitions provided in Recommendations E.600, 2 Recommendation E.760 (03/2000) 4 Abbreviations This Recommendation uses the following abbreviations: BS Base Station GSM IMT-2000 International Mobile Telecommunications-2000 Global System for Mobile communications ISC LE MMF MSC MT TE 5 5.1 International
37、 Switching Centre Local Exchange Mobility Management Function Mobile Switching Centre Mobile Terminal Terminal Exchange Introduction One unique feature characterizing the traffic demand of mobile users is spatial volatility. This relates to the changing geographical origin (or destination) of traffi
38、c associated with the same mobile user once a connection has been established (in-call mobility) and is due to user terminal mobility. Another aspect of terminal mobility relates to users changing their geographical location in-between calls (inter-call mobility): this results in a dynamic associati
39、on between the identifier of the actual terminal device used by a user and the network attachment point for calls originated by (or destined to) the same user. 5.2 As a consequence of traffic volatility combined with traffic source activity and spectrum reuse typical of cellular systems, the radio c
40、hannel quality is space- and time-dependent and appropriate actions, e.g. handover or combining, may be performed by the system to help maintain a minimum level for the quality of service. Although these actions may result in a consumption of the same resources utilized for accommodating call demand
41、s, the characterization of the related processes depends, among others, on how radio resources are engineered and managed. For this reason the characterization of these processes is covered in Recommendations of the E.750-series especially concerned with traffic dimensioning methods for land mobile
42、systems. 5.3 One way of capturing traffic volatility for engineering purposes is via a distribution in space and time of the user population over a considered area. This distribution shall then be mapped onto user demand, while retaining the space and time dependence. Factors affecting this distribu
43、tion include: o environment type (indoor/outdoor, business, residential, etc.); geography of and mobility patterns on the considered area (open space, urban layout, city mobility characteristics (pedestriancar mobility behaviour, speed, etc.); o precinct, etc.); o o service penetration. 5.4 Although
44、 efficient use of the available spectrum might be attained by using various forms of dynamic bandwidth allocation to cope with the volatility of mobile traffic, most existing systems are dimensioned according to a worst-case approach with relationship to a static population of users. This implies th
45、at the highest traffic demand insisting on a given area (usually corresponding to a cell) is estimated and the number of radio channels related to that area is determined accordingly. The estimate is based on such data as density of residing population, service penetration, geographic characteristic
46、s, traffic per subscriber, etc. Recommendation E.760 (03/2000) 3 This Recommendation is concerned with the worst-case approach as defined above; estimation of the traffic demand based on explicit consideration of the time and space traffic volatility is for further study. 5.5 Finally, to decouple th
47、e traffic demand characterization fiom the dimensioning and control procedures and harmonize with the methodology used for traffic engineering for fixed networks and services, the traffic demand processes for systems supporting mobile services have to be kept distinct fiom processes induced by netwo
48、rk operation, such as channel quality maintenance and handover handling. 6 Estimation of traffic demand for cellular networks 6.1 Rationale 6.1.1 For traffic engineering of cellular systems, information on geographical population distribution is of vital importance to an operator. For new entrants t
49、o a market, this information can normally only be estimated using published census information. This may vary in resolution, with the better ones being rather detailed, and may resolve down to municipal or district level. From the census database and the size of the geographical area, it is possible to estimate the population density for the location. Together with the year-on-year user penetration forecast and the average traffic intensity per subscriber, the traffic demand can be obtained. 6.1.2 In parallel with the traffic engineering process, radio coverage planning is also performed t