1、INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STAN DAR DI ZATI ON SECTOR OF ITU E774 (1 0/96) SERIES E: TELEPHONE NETWORK AND ISDN Quality of service, network management and traffic engineering - Traffic engineering - Mobile network traffic eng i neeri ng Network grade of service par
2、ameters and target values for maritime and aeronautical mobile services I TU-T Reco m men da ti on E. 774 (Previously CCITT Recommendation) STDvITU-T RECMN E-77lr-ENGL L77b 9 48b257L Ob26387 82T ITU-T E-SERIES RECOMMENDATIONS TELEPHONE NETWORK AND ISDN OPERA TION, NUMBERING, ROUTING AND MOBILE SERVI
3、CES I/ INTERNATIONAL OPERATION E. 100-E.229 OPERATIONAL PROVISIONS RELATING TO CHARGING AND ACCOUNTING IN E.230-E.299 Il TH E INTERNATIONAL TELEPHON E SERVICE UTILIZATION OF THE INTERNATIONAL TELEPHONE NETWORK FOR NON- E.300-E.329 TELEPHONY APPLICATIONS ISDN PROVISIONS CONCERNING USERS E.330-E.399 Q
4、UALINOF SERVICE, NETWORK MANAGEMENT AND TRAFFIC ENGINEERING NETWORK MANAGEMENT E.400-E.489 International service statistics E.400-E.409 International network management E.410-E.419 Checking the quality of the international telephone service TRAFFIC ENG I N E ER1 NG Measurement and recording of traff
5、ic Forecasting of trafic E.420-E.489 E.490-E.799 E.490-E.505 E.506-E.509 Determination of the number of circuits in manual operation E.510-ES19 Determination of the number of circuits in automatic and semi-automatic operation E.520-ES39 Grade of service E.540-E.599 Definitions E.600-E.699 ISDN trafi
6、c engineering E.700-E.749 Mobile network traffic engineering E.750-E.799 E. 8 OO-E. 899 QUALITY OF TELECOMMUNICATION SERVICES: CONCEPTS, MODELS, OBJECTIVES AND DEPENDABILITY PLANNING Terms and definitions related to the quality of telecommunication services E.800-E.809 Models for telecommunication s
7、ervices E.810-E.844 Objectives for quality of service and related concepts of telecommunication E.845-E.859 services Use of quality of service objectives for planning of telecommunication networks E.860-E.879 Field data collection and evaluation on the performance of equipment, networks and services
8、 E.880-E.899 I For further details, please refer to ITU-T List of Recommendations. STD*ITU-T RECMN E.77i-ENGL 177b iBb2.571 ObZb370 591 W ITU-T RECOMMENDATION E.774 NETWORK GRADE OF SERVICE PARAMETERS AND TARGET VALUES FOR MARITIME AND AERONAUTICAL MOBILE SERVICES Summary This Recommendation identif
9、ies the Grade of Service (GOS) parameters and associated target values for circuit-switched services in both satellite- and terrestrial-based maritime and aeronautical systems. The GOS parameters and target values are confined to the mobile network segment of end- to-end connections. Source ITU-T Re
10、commendation E.774 was prepared by ITU-T Study Group 2 (1993-1996) and was approved under the WTSC Resolution No. 1 procedure on the 8th of October 1996. STD-ITU-T RECMN E-774-ENGL L77b 48b257L ObZb39L 488 D FOREWORD ITU (International Telecommunication Union) is the United Nations Specialized Agenc
11、y 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 wor
12、ldwide 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 covered
13、by the procedure laid down in WTSC Resolution No. 1 (Helsinki, March 1-12, 1993). 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
14、used for conciseness to indicate both a telecommunication administration and a recognized operating agency. O ITU 1997 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 p
15、ermission in writing from the ITU. Recommendation E.774 (10/96) II 1 2 3 4 5 6 6.1 . STD-ITU-T RECMN Ea774-ENGL 199b 48b2591 ObZb392 314 CONTENTS Page Scope Related Recommendations . Definitions Abbreviations . Introduction GOS parameters and target values GOS parameters 6.1.1 Probability of link bl
16、ocking for the terrestrial/satellite subsystem . 6.1.2 Probability of blocking at LES/GES . 6.1.3 Probability of unsuccessful handover for terrestrial based systems 6.1.4 Authentication delay . 6.2 Target values for GOS parameters . 7 History Recommendation E.774 (10/96) 1 1 1 2 2 5 . 111 STD-ITU-T
17、RECMN E.77q-ENGL L77b = qb257L ObZb393 250 STD-ITU-T RECMN E.774-ENGL 197b D 48b2571 Ob2b374 177 W Recommendation E.774 NETWORK GRADE OF SERVICE PARAMETERS AND TARGET VALUES FOR MARITIME AND AERONAUTICAL MOBILE SERVICES (Geneva, 1996) 1 Scope This Recommendation outlines the general consideration fo
18、r identifjhg Grade of Service (GOS) parameters for the maritime and aeronautical circuit-switched services and defines the target values under normal and heavy traffic load conditions. These parameters are defined - and their target values specified - assuming that the network and the network compon
19、ents are operating in their normal mode (Le. are fully operational). Further, the parameters and their target values assume normal (as opposed to distress or emergency) traffic. Mobile services in terrestrial- and satellite-based maritime and aeronautical systems can be circuit- or packet-switched,
20、This Recommendation is initially concerned with circuit-switched user plane traffic and normal (as opposed to distress and safety) traffic. Packet-switched traffic is for further study. This Recommendation is applicable to the terrestrial/satellite subsystem. 2 Related Recommendations The following
21、Recommendations contain material that is either relevant to or provides background for this Recommendation: - - CCITT Recommendation ES00 (1 992), Trafic intensitjv measurement principles. ITU-T Recommendation E.600 (1 993), Terms and defznitions of trafic engineering. - ITU-T Recommendation E.75 1
22、(1 996), Reference connections for trafic engineering of land mobile networks. ITU-T Recommendation E.752 (1 996), Reference connections for trafic engineering of maritime and aeronautical systems. ITU-T Recommendation E.770 (1 993), Land mobile and fzxed network interconnection trafic grade of serv
23、ice concept. ITU-T Recommendation E.77 1 (1 996), Network grade of service parameters and target values for circuit-switched public land mobile services. ITU-T Recommendation E.773 (1996), Maritime and aeronautical mobile grade of service concept. ITU-T Recommendation F. 1 10 (1996), Operational pro
24、vision for the maritime mobile service. 3 Definitions Definitions relevant to this Recommendation are contained in Recommendation E.752. The following definitions complement those in Recommendation E.752. Recommendation E.774 (1096) 1 STD-ITU-T RECMN E-774-ENGL L99b qBb2.591 Ob2b395 023 3.1 normal t
25、raffic load: Average of all week days busy hour traffic for the three busiest months of the year excluding December - (Average Busy Season Busy Hour, ABSBH). 3.2 high traffic load: Mean of the three highest busy hour traffic in the same period as the normal load subject to the condition that the thr
26、ee values fall on different days - (Highest Busy Season Busy Hour, HBSBH). 4 Abbreviations For the purposes of this Recommendation, the following abbreviations are used. ABSBH AES Aircraft Earth Station GES Ground Earth Station Average Busy Season Busy Hour GOS Grade of Service GS Ground Station HBS
27、BH LES Land Earth Station SES Ship Earth Station TSS Terrestrial/Satellite Subsystem Highest Busy Season Busy Hour 5 Introduction This Recommendation proposes network Grade of Service (GOS) parameters and target values for both satellite- and terrestrial-based maritime/aeronautical mobile networks.
28、Although these systems provide circuit- and packet-switched services, this Recommendation defines the parameters and the target values only for the circuit-switched traffic. The parameters and target values for the signalling traffic are covered under separate Recommendations. Note that in aeronauti
29、cal mobile-satellite systems the high traffic load (HBSBH) is typically 30% greater than the normal traffic load (ABSBH). Hence the GOS criteria for the ABSBH typically would not meet that of HBSBH and therefore the aeronautical mobile-satellite systems must be dimensioned for the HBSBH. This Recomm
30、endation covers GOS parameters and target values for both terrestrial- and satellite-based mobile networks. 6 6.1 GOS parameters The GOS parameters for circuit-switched traffic specifiec on an end-to-end basis depend on a number of factors. These include user behaviour, routing arrangements such as
31、priority offered in the GOS parameters and target values This definition is derived from Recommendation E.500, modified to reflect the peculiar diurnal and seasonal profile of mobile satellite telecommunications using SCPC (Single Channel Per Carrier) demand assigned channel allocation. 2 Recommenda
32、tion E.774 (10196) STD-ITU-T RECMN E.774-ENGL L77b = 48b257L Ob2b37b TbT different stages of connection, and the time difference between busy hours associated with different segments of the connection. A successful call attempt is one for which the system has successfully assigned a channel and rout
33、ed a call attempt to the designated terminal address. A non-pre-empted call attempt to a busy end-user should be treated as successful from the viewpoint of the GOS performance. In this Recommendation, the following traffic GOS parameters are specified for mobile circuit- switched services. - - - -
34、authentication delay. probability of link blocking for the terrestrial/satellite subsystem; probability of blocking at LES/GES; probability of unsuccessful handover for terrestrial-based systems; 6.1.1 Probability that an offered call will be blocked (loss probability) during the busy hour due to sh
35、ortage of satelliteterrestrial circuits in the terrestrial/satellite subsystem segment. Different GOS target values for link blocking probability are applicable to carry Average Busy Season Busy Hour (ABSBH) traffic and Highest Busy Season Busy Hour (HBSBH) traffic. Probability of link blocking for
36、the terrestriahatellite subsystem 6.1.2 Probability that an offered call will fail due to shortage of channel units and terrestrial link to fixed network at LES/GES in the ground subsystem. As in the case of the probability of link blocking for the terrestriahatellite subsystem, the target values ar
37、e defined for ABSBH and HBSBH traffic load conditions. Probability of blocking at LEWGES 6.1.3 This parameter is the probability that a handover attempt fails because of lack of radio resources in the target cell, or because of a lack of free resources for establishing the new network connection. Th
38、e failure condition is based either on a specified time interval since the handover request was first issued or on a threshold on signal strength. (Satellite-based systems can be designed without the possibility of handover between spot beams, e.g. the original Inmarsat system.) Probability of unsuc
39、cessful handover for terrestrial based systems 6.1.4 Authentication delay Authentication of an automatic credit/charge/calling card call, originating from a mobile station involves a preliminary (format) verification at the SEYAES before the information is passed to the LESGES for further processing
40、. Authentication delay is defined as the time elapsed since the initial verification is performed at the LES/GES to the time the caller receives the authentication message. The final responsibility for meeting the target value for the authentication delay rests with the mobile service provider, alth
41、ough the total authentication procedure may be accomplished by using a combination of mobile and fixed network facilities. These latter are credit card agency database systems chosen by the mobile service provider and typically contribute a substantial portion to the overall authentication delay. Th
42、e GOS parameters recommended for maritime and aeronautical circuit switched-services are summarized in Table 1. Recommendation E.774 (10/96) 3 STD-ITU-T RECMN E-77i-ENGL L99b = iBb259L Ob2b397 9Tb Probability of link blocking for Probability of blocking at terrestriaihateIlite subsystem LES/GES Prob
43、ability of unsuccessful handover Authentication delay for mobile originated credit card calls TABLE 1/E.774 GOS parameters for maritime and aeronautical mobile services M-F F-M M-M M-F F-M M-M A A A A A A A A A A A A FS FS FS NA NA NA FS FS FS A NA A GOS parameters I Terrestrial mobile network I Sat
44、ellite mobile network 6.2 GOS target values for circuit-switched services are given in Table 2. Target values for GOS parameters 4 Recommendation E.774 (10/96) STD*ITU-T RECMN E-774-ENGL L77b 48b257L ObZb378 832 Terrestrial mobile network TABLE 2E.774 Target values for GOS parameters - circuit-switc
45、hed services Satellite mobile nehvork GOS parameters Probability of Link blocking for terrestrial/satellite Subsystem Normal Load High Load Probability of blocking at LESIGES Normal Load High Load Probability of unsuccessful handover Authentication delay (only for mobile originated calls, normal and
46、 high load) I I I FS FS Maritime I Aeronautical I Maritime I Aeronautical FS 2% 2% 10% 10% FS 1 Yo 1 Yo 2% 2% 95% of calls to be authenticated within 115.0 secs 95% of calls to be authenticated within 112.0 secs NA FS I FS I NA I FS FS NA Not Applicable FS Further Study NOTE - Authentication delay r
47、efers to the overall delay as defined in 6.1.4. 7 History This is the first issue of Recommendation E.774. Recommendation E.774 (10/96) 5 STD-ITU-T RECMN E-77Y-ENGL L77b m 48b259L Ob2b377 777 m ;enes A Series B Series C Series D Series E Series F Series G Series H Series I Series J Series K Series L
48、 Series M Series N Series O Series P Series Q Series R Series S Series T Series U Series V Series X Series Z ITU-T RECOMMENDATIONS SERIES Organization of the work of the ITU-T Means of expression General telecommunication statistics General tariff principles Telephone network and ISDN Non-telephone
49、telecommunication services Transmission systems and media Transmission of non-telephone signals Integrated services digital network Transmission of sound-programme and television signals Protection against interference Construction, installation and protection of cables and other elements of outside plant Maintenance: international transmission systems, telephone circuits, telegraphy, facsimile and leased circuits Maintenance: international sound-programme and television transmission circuits Specifications of measuring equipment Telephone transmission qual
