1、INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU E.161 (02/2001) SERIES E: OVERALL NETWORK OPERATION, TELEPHONE SERVICE, SERVICE OPERATION AND HUMAN FACTORS International operation - Numbering plan of the international telephone service Arrangement of digit
2、s, letters and symbols on telephones and other devices that can be used for gaining access to a telephone network ITU-T Recommendation E.161 (Formerly CCITT Recommendation) ITU-T E-SEIUES RECOMMENDATIONS OVERALL NETWORK OPERATION, TELEPHONE SERVICE, SERVICE OPERATION AND HUMAN FACTORS INTERNATIONAL
3、OPERATION Definitions General provisions concerning Administrations General provisions concerning users Operation of international telephone services Numbering pian of I the international telephone service International routing plan Tones in national signalling systems Numbering plan of the internat
4、ional telephone service Maritime mobile service and public land mobile service OPERATIONAL PROVISIONS RELATING TO CHARGING AND ACCOUNTING IN THE INTERNATIONAL TELEPHONE SERVICE Charging in the intemational telephone service Measuring and recording call durations for accounting purposes UTILIZATION O
5、F THE INTERNATIONAL TELEPHONE NETWORK FOR NON- TELEPHONY APPLICATIONS General Phototelegraphy ISDN PROVISIONS CONCERNING USERS INTERNATIONAL ROUTING PLAN NETWORK MANAGEMENT International service statistics Intemational network management Checking the quality of the international telephone service Me
6、asurement 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 Definitions Traffic engineering for IP-networks ISDN trafic engineering Mobile netw
7、ork traffic engineering TRAFFIC ENGINEERING QUALITY OF TELECOMMUNICATION SERVICES: CONCEPTS, MODELS, OBJECTIVES AND DEPENDABILITY PLANNING Terms and definitions related to the quality of telecommunication services Models for telecornmunication services Objectives for quality of service and related c
8、oncepts 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 WE. 103 E.104-E.119 E.120-E.139 E. 140-E. 159 E.160-E. 169 E.170-E.179 E. 180-E. 189
9、E. 190-E. 199 E.200-E.229 E.230-E.249 E.260-E.269 E.300-E.3 19 E.320-E.329 E.330-E.349 E.350-E.399 E.4O-E.409 E.410-E.419 E.420-E.489 E.490-ES05 E.506-ES09 ES 10-Es19 E.520-ES39 E. 540-E. 5 99 E. 600-E. 649 E.650-E.699 E.700-E.749 E.750-E.799 E.8WE.809 E.810-E.844 E.860-E.879 E.880-E.899 E. 845-E.85
10、9 For further details, please refer to the list of ITU-T Recommendations. ITU-T Recommendation E.161 Arrangement of digits, letters and symbols on telephones and other devices that can be used for gaining access to a telephone network Summary This Recommendation has been amended to include the prefe
11、rred option for showing the relationship between letters and digits, where both appear on a keypad or dial. Additionally, in order to assist blind or visually impaired people in identifying the dialling push-buttons, it has been recommended that the button with the digit “5“ be marked with a tactile
12、 identifier. Source ITU-T Recommendation E.161 was revised by ITU-T Study Group 2 (2001-2004) and approved under the WTSA Resolution 1 procedure on 2 February 2001. ITU-T E.161(02/2001) i FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field o
13、f 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 a worldwide basis. The World
14、Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In so
15、me 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 telecommunication administration and a recogniz
16、ed 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 applicability of claimed Intell
17、ectual Property Rights, whether asserted by ITU 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 implement this Recommendation.
18、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 means, electronic or mechanical,
19、 including photocopying and microfilm, without permission in writing from ITU. 11 ITU-T E.161(02/2001) CONTENTS Page 1 2 3 3.1 3.2 3.3 3.4 3.5 3.6 4 4.1 4.2 Use of digits and letters on telephone sets . Rotary dials Push-buttons or keys . Ten push-buttons 3.1.1 Arrangement and numbering 3.1.2 Symbol
20、s . 12 push-buttons 3.2.2 Symbols . Dual mode and engraving . Design of symbols 3.2.1 Arrangement Position of figures, letters and symbols on push-button sets Tactile identifier on the “5“ button Additional push-buttons for use on telephones Specific recommendations General . 4.2.1 Register recall p
21、ush-button ITU-T E.161 (02/2001) 1 1 2 2 2 3 3 3 3 4 4 4 5 . 111 ITU-T Recommendation E.161 Arrangement of digits, letters and symbols on telephones and other devices that can be used for gaining access to a telephone network 1 Use of digits and letters on telephone sets 1.1 For the automatic intern
22、ational service, it is preferable that the national numbering plan should not involve the routine use of letters, e.g. to designate local exchanges (associated with digits). However, letters may be used to designate the names of particular services, facilities, organizations or individual subscriber
23、s. The allocation of such mnemonics (and their equivalent national numbers) is a national matter. 1.2 For countries using letters in telephone numbers, it would be helpful to include in the directory a table for converting the letter codes into digits (see 2.2). 1.3 It would also be desirable to req
24、uest those subscribers assigned mnemonic codes (particularly if they have considerable international traffic) to show on their letterheads, below their national telephone number, the international number with digits only. (See ITU-T E. 123.) 2 Rotary dials 2.1 should be arranged in the following ord
25、er: 1,2,3, . , O as shown in Figure 1. For countries which have not yet adopted any specific type of dial, the digits on the dial Figure 1/E.161- Rotary dial 2.2 relationships between the letters and the digits are as shown below: Where letters as well as digits appear on a dial or its surround, the
26、 recommended 1 . 2ABC 3 DEF 4 GHI 5 JIU 6 MNO 7 PQRS 8 TUV 9 WXYZ O ITU-T E.161(02/2001) 1 3 Push-buttons or keys 3.1 Ten push-buttons 3.1.1 Arrangement and numbering The standard arrangement and numbering for push-buttons corresponding to the digits 1 to O is as shown below: 123 456 789 O Extensive
27、 research has shown that this arrangement leads to shorter entry times and lower error rates than other arrangements. Where a need exists within an Administration for a 2 x 5 array or a 5 x 2 array for use on special telephone apparatus, the arrays should be as shown below: 12 12345 34 67890 56 78 9
28、0 NOTE - User dialling performance on these special arrays is slightly inferior to that on the standard array given above. While numbering plans using only digits are widely used, there are advantages in allowing the use within these numbering plans of alphabetic equivalents for frequently used numb
29、ers (see 1.1). The use of letters rather than numbers is also convenient for data entry (interactive applications, entry of passwords, etc.) after a call has been established. The recommended relationships between the letters and the digits are the same as shown in 2.22, including its footnote. Care
30、 must be taken when letters and a digit are associated with a key such that legibility of the digit is not impaired. The preferred and recommended arrangement for the keys of a separate numeric keypad on a multi- functional terminal used both for the entry of telephone number information and data is
31、 the standard arrangement shown at the beginning of this clause. Exceptionally, for devices intended to be used principally for data entry but which may sometimes be used to enter telephone number information, the arrangement whereby the fust and the third row of the standard ITU-T arrangement are i
32、nterchanged may be used3. Also exceptionally, telephone number information may be input from the row of numeric keys. 1234567890 of an alpha-numeric keyboard. An annotated list of literature references is available in the article cited in i. On the North American dials and keypads, the digit O is as
33、sociated with the word “operator“. The corresponding IS0 Standard can be found in ISODEC 9995-4, entitled “Znforrnation technology - Keyboard layouts for text and office systems - Part 4: Numeric section“. 2 ITU-T E.161 (02/2001) 3.1.2 Symbols The symbols for these buttons are the digits 1 to O as i
34、ndicated in the arrangement of 3.1.1. These buttons are to be known as button 1, button 2, etc. 3.2 12 push-buttons 3.2.1 Arrangement For 12 push-buttons the standard arrangement shown in 3.1.1 is extended by two additional buttons, one to the left and the other to the right of the button O, thus ma
35、king a pattern of four horizontal rows of three buttons each forming a 4 x 3 array. Two buttons may also be added to the 5 x 2 array shown in 3.1.1. These should be located below and in line with buttons 9 and O, thus making a 6 x 2 array. 3.2.2 Symbols On the 4 x 3 array, the symbol on the button w
36、hich is immediately to the left of the button O (on the 6 x 2 array, the corresponding button is located below 9, and on the 2 x 6 array to the right of button 5) and which, according to UIT-T Q.23, is used to transmit the frequency pair 941 Hz and 1209 Hz, should have a shape easily identified as t
37、he general shape shown in Figure 2. TO1 031 90-93 Figure 2/E.161 The symbol will be known as the star or the equivalent term in other languages. On the 4 x 3 array, the symbol on the button which is immediately to the right of the button O (in the 6 x 2 array, the corresponding button is located bel
38、ow the buttono) and which, according to UIT-T Q.23, is used to transmit the frequency pair 941 Hz and 1477 Hz, should conform in shape to the specifications given in Figure 3 or 4. This symbol shall consist of four lines of equal length (b) forming two pairs of parallel lines. One pair is horizontal
39、 while the other is vertical or inclined to the right at an angle a of 800 as shown in Figure 4. It will be seen that two pairs of parallel lines overlap. The ratio a/b where a is the overlap, shall be between 0.08 and O. 18. a = 90“ a 5 = 0.08 - a = 80 with a/b close to the upper limit of O. 18. Th
40、e symbol may be referred to as the square or the most commonly used equivalent term in other languages4. The additional buttons with these symbols will be placed as shown below: Standard 4 x 3 array 123 6x2array 12 2x6array 12345* 456 34 67890# 789 *O# 56 78 90 *# 3.3 Dual mode and engraving Dual mo
41、de and engraving of the buttons * and # are acceptable on telephones and on multi- functional terminals. 3.4 Design of symbols Symbol size and the line thickness should be appropriate to provide optimal recognition. 3.5 The figures, letters and symbols used for dialling should be unambiguously assoc
42、iated with the corresponding buttons, preferably, if adequate space is available, by being on the faces of the buttons themselves. Position of figures, letters and symbols on push-button sets 4 In some countries an alternative term (e.g. “hash“, “pound“ or “number sign“) may be necessary for this pu
43、rpose, particularly where the form in Figure 4 is commonly used, in which case it is useful to select and to recommend a preferred term for consistent use nationally. 4 ITU-T E.161 (02/2001) 3.6 TO assist blind and visually impaired people in identifying the dialling push-buttons and otherwise to fa
44、cilitate dialling under low light conditions, it is recommended that the button with the “5“ be marked with a tactile identifier so that the button can be identified by the sense of touch. The preferred locations of the tactile identifier are: - - - It is recommended that the tactile identifier is p
45、ositioned in such a way that it will not obscure the legibility of the marking on the “5“ button (see Figure 5). Tactile identifier on the “5“ button5 In the middle of the “5“ button. As near the middle of the “5“ button as possible. On the surface of the “5“ button that is pressed when it is activa
46、ted. TO208520-00 Figure YE.161 If none of these locations can be used, e.g. on small keys, alternative positions of the tactile identifier are acceptable. However, the tactile identifier shall unambiguously identify the “5“ button. The preferred form of the tactile identifier on the “5“ button is a
47、distinct raised round dot (see Figure 6). The recommended dimensions of the raised round dot are: - - Height 0.6 mm (+0.2 mm). Diameter 1.5 mm (+0.2 mm). 1.5 k 0.2 111111 TO208530-O0 Figure 6/E.161 4 Additional push-buttons for use on telephones 4.1 General For purposes other than dialling, addition
48、al push-buttons may be required on a telephone. For example, a telephone may have a push-button to recall during an active call, control logic (e.g. a register) or an operator, or to effect the transfer of an active call to another station. To prevent 5 The material of this clause is taken from an E
49、TSI Standard: ES 201 381 V1.l.l 2. ITU-T E.161(02/2001) 5 subscriber confusion it may be desirable that the symbols used on those push-buttons which have identical functions be standardized. 4.2 Specific recommendations 4.2.1 Register recall push-button For the recall of a register during an active call, the following methods are possible: - a switchhook flash; - a depression of one of the push-buttons of the normal 10 or 12 button array; - a depression of another push-button specially provided for this purpose - the register recall push- button. From the human factors viewpoint the de
