1、INTERNATIONAL TELECOMMUNICATION UNION)45G134 % TELECOMMUNICATIONSTANDARDIZATION SECTOROF ITU4%,%0(/.%G0G0.%47/2+G0G0!.$G0G0)3$./0%2!4)/. G0G0.5-“%2). G0G02/54).!.$G0G0-/“),%G0G03%26)#%02%3%.4!4)/.G0G0/&G0G02/54).G0G0$!4!)45G134G0G0RecommendationG0G0% (Extract from the “LUEG0“OOK)NOTES1 ITU-T Recomme
2、ndation E.149 was published in Fascicle II.2 of the Blue Book. This file is an extract from theBlue Book. While the presentation and layout of the text might be slightly different from the Blue Book version, thecontents of the file are identical to the Blue Book version and copyright conditions rema
3、in unchanged (see below).2 In this Recommendation, the expression “Administration” is used for conciseness to indicate both atelecommunication administration and a recognized operating agency. ITU 1988, 1993All rights reserved. No part of this publication may be reproduced or utilized in any form or
4、 by any means, electronic ormechanical, including photocopying and microfilm, without permission in writing from the ITU.Fascicle II.2 - Rec. E.149 1Recommendation E.149Fascicle II.2 - Rec. E.149PRESENTATION OF ROUTING DATA1 When semiautomatic or automatic service is initially introduced between two
5、 countries it is recommended thata routing document be prepared by each Administration and an adequate number of copies exchanged. This routingdocument should be prepared as a booklet of A5 size (14.8 21.0 cm), and be divided into three sections.It seems important to keep the information up to date
6、by exchanging data of the following types:a) Major routing changes involving existing routes and/or offices for which data have been previouslysupplied. Such information should be made available at least three months prior to the effective date of thechange. In this respect, the importance of notifi
7、cation will be governed by the volume and characteristics ofthe traffic affected.b) Other routing changes in a countrys networks which were not sufficiently important to be handled asdescribed in a) above. This information should be supplied annually or more frequently whencircumstances justify this
8、 course.When forwarding routing changes under a) and b), forms on the model of Tables A or B in Section 2 of therouting document should be used, indicating whether the change is a revision or a new edition. In principle, a completereprinting of the routing document is desirable from time to time. Ho
9、wever, the frequency of production of a revisedset of routing information should be left to the discretion of the issuing Administration. It is recommended that arevised set should be brought out not less frequently than once in five years.Where an Administration finds it impracticable to provide al
10、l of the routing data in the manner recommendedabove, it is desirable that it adhere to this Recommendation to the maximum extent possible.2 Information to be entered on the routing document2.1 Section 1 Explanatory notes2.1.1 The issuing Administration should include the following items:2.1.1.1 The
11、 numbering plan arrangements should be explained briefly, and the trunk prefix (if any) used in the nationalnetwork should be quoted. Any useful information about the total number of digits in the national numbering systemshould be supplied.2.1.1.2 The country code.2.1.1.3 Language digits according
12、to the availability of language assistance on incoming calls.2.1.1.4 Name(s) of international exchange(s) used for incoming traffic. In specifying the name of the internationalexchange it should be indicated if it serves for continental and/or intercontinental traffic. If there is more than oneexcha
13、nge, an explanation should be given as to which part of the national network each exchange serves by quoting thedigit(s) of the trunk code which are necessary for this purpose. Where there is no uniform system for all incomingtraffic to a country, the explanatory notes should make clear the specific
14、 instructions proper to each outgoing country.2.1.1.5 It should be explained how subscribers in other localities than those listed in Section 2 can be reached (forinstance by code 11).2.1.1.6 A table showing how to reach special services such as: supervisor, delay operator, transit calls, calls to/f
15、rom ships, phototelegraph calls, collect calls, requests for information, personal calls for which word has been left at the called station.2 Fascicle II.2 - Rec. E.1492.1.1.7 If functions described in 2.1.1.6 are performed on a decentralized basis, routing data will be indicated inSection 2, Tables
16、 A and B. It should be observed that if the outgoing operator does not speak any of the languagesindicated, she should direct her call to the appropriate incoming international operator.2.1.1.8 A table of public holidays when general business and financial institutions may be closed.2.1.1.9 It is re
17、commended that a specific address be provided by each Administration to receive routing informationand to handle questions regarding internal routing arrangements and inquiries about entries in the routing document.2.2 Section 2 Instructions for preparing and using routing tablesThe routing informat
18、ion considered appropriate for distribution to other Administrations should be set out in astandard form for ease of interpretation and in sufficient detail to enable the controlling operator to set up a connectionwithout recourse to the incoming international operator on more than 5% of the calls.I
19、t is in the interests of Administrations to ensure that adequate and accurate information is available tocontrolling operators in order that operating costs at both outgoing and incoming exchanges may be kept to the lowestfigure commensurate with the cost of production and maintenance of the routing
20、 information.It is recommended that the routing information should be produced in either of the forms shown below, i.e.Table A or Table B.TABLE A(of the routing document)Name of localityRouting codeto reach subscribersRouting codeto reach operatorsDirectory1234How to fill in Table A:Column 1 Name of
21、 localityThis is the name of the community, e.g., city, town or village, which subscribers generally use to designate where theirtelephone service is provided.Column 2 Routing code to reach subscribersThe routing code (trunk code) used to reach telephones in the locality.Column 3 Routing code to rea
22、ch operatorsThe routing code combined with a standardized operator code (see 2.1.1.7 in explanatory notes) which permits reachingan operator performing a specific function for the locality.Language indicatorIn column 3, insert, using a letter code, the language(s) spoken by the local operators. If t
23、he language(s) are spoken by alloperators serving the localities listed in column 1, an explanatory note keyed to column 3 would suffice for indicating the commonlanguage(s). An explanation of the code should be annexed.Column 4 DirectoryWhere applicable the reference number or letter which indicate
24、s the particular directory column or section where thetelephone number for the locality may be found.Fascicle II.2 - Rec. E.149 3TABLE B(of the routing document)Routing code to reach operators forNameof localityRouting codeto reach subscribersCompleting callsand verifyingstation conditionsVerifyings
25、tation conditionsonlyRequests forinformationDirectory1 2 3a 3b 3c 4How to fill in Table B:Columns 1, 2 and 4See under Table A.Column 3aThis column should contain the complete code that enables a controlling operator to gain access to an incoming operatorwho is in a position to extend the connection
26、to the called number and verify the station conditions.Column 3bThis column should contain the complete code that enables a controlling operator to gain access to an operator who canverify the conditions on a called station, e.g., that the number is of a working line, that there is no reply or that
27、the line is engaged.Column 3cThis column should contain the complete code that enables a controlling operator to obtain the subscriber of a person in thelocality in question.As it is important that the controlling operator should know that she will be able to understand the called operator, anindica
28、tor should be used, as described in the “language indicator of Table A”. If separate routing codes are necessary to giveaccess to operators speaking specific languages at the incoming exchanges, these should be shown with the appropriate indicationagainst each code. A routing code in column 3a shoul
29、d not be repeated in column 3b.The country where uniform information is available throughout its territory for access to its operators handling:a) the completion of inward calls and verifying station conditions,b) verification of station conditions only, andc) local telephone number information,ordi
30、narily would use Table A. The method of access to these particular services would be indicated in Section 1 aboveand need not be repeated against the individual items in the routing schedule.In the case where a country provides differing access points beyond its international exchange for any or all
31、 ofthe three categories a), b) and c) mentioned above, it would use Table B. The specific routing information to giveaccess to the available point should be shown in sub-columns of column 3, headed respectively 3a, 3b and 3c. Whereno facility exists for a particular locality there should be no entry
32、 of any kind, thus indicating the need for thecontrolling operator to call the international incoming operator.2.3 Section 3 List of trunk (area) codes in numerical orderIt is in the interest of Administrations to incorporate this information in the routing document not only for thecontrolling opera
33、tor for maintenance (e.g. fault report) and for proper application of Recommendation E.422 1 (e.g.dialling of wrong trunk code).Furthermore, this information can be used to prevent calls with improper routing codes from seizing theinternational circuits.It is recommended that the information be give
34、n in the form shown in Table C.4 Fascicle II.2 - Rec. E.149TABLE C(of the routing document)Routing codeFirst digitsafter routing codeNumber of digitsafter routing codeIdentificationof section or area1234How to fill in Table C :Column 1Routing code (trunk code) used to reach telephones in the section
35、 or area.Column 2First digit to be dialled after the routing code (not required when the number of digits after the routing code is constant).Column 3Number of digits after the routing code not required when the national (significant) number has a fixed length.Column 4Name of the section or area.References1 CCITT Recommendation Observations on international outgoing telephone calls for quality of service,Rec. E.422.
