1、INTERNATIONAL TELECOMMUNICATION UNION)45G134 - TELECOMMUNICATIONSTANDARDIZATION SECTOROF ITU-!).4%.!.#% ).4%2.!4)/.!,G0G04%,%0(/.%G0G0#)2#5)433).!,).G0G0!.$G0G037)4#().2/54).%G0G0-!).4%.!.#%G04%343!.$G0G0-%!352%-%.43)45G134G0G0RecommendationG0G0- (Extract from the “LUEG0“OOK)NOTES1 ITU-T Recommendat
2、ion M.732 was published in Fascicle IV.1 of the Blue Book. This file is an extract fromthe Blue 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 remain u
3、nchanged (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 by
4、any means, electronic ormechanical, including photocopying and microfilm, without permission in writing from the ITU.Fascicle IV.1 - Rec. M.732 1Recommendation M.732Fascicle IV.1 - Rec. M.732SIGNALLING AND SWITCHING ROUTINE MAINTENANCE TESTSAND MEASUREMENTSThe object of routine maintenance tests and
5、 measurements of signalling and switching is to detect changes inthe functioning of signalling and switching which are likely to cause a reduction in the quality of service provided.These changes are those which occur in relation to the values indicated in the specifications for the signalling syste
6、msconcerned (see the pertinent Series Q Recommendations). In the various sections of the Series Q Recommendations,limits are laid down within which: no action is necessary, action is required by the maintenance service at either of the terminal exchanges.For Signalling Systems Nos. 4, 5, 6, 7 and R2
7、 reference should be made to Recommendations Q.139 1,Q.163 2, Q.295 3, Q.707 4 and Q.490 5 respectively which contain guidance on the methods to be used forsignalling and switching routine tests, together with the minimum frequencies at which such tests should be carried out.On routes where ATME No
8、 2 (Recommendation O.22 6) is in use, many of the required tests and measurements canbe performed by that equipment. Supervision and fault localization functions included in the exchange and/or in thetransmission system also reduce or remove the need for routine maintenance tests and measurements.W
9、here staffing arrangements permit, manual and semi-automatic routine maintenance of signalling andswitching equipment should be done at times when traffic is light. Any routines performed during normal working hoursmust be carried out with great care to ensure that the effect on live traffic is mini
10、mized.In stored program control (SPC) and digital exchanges many of the required checks for correct functioning ofsignalling and switching equipment are carried out automatically by supervisory functions within the exchange, thusremoving the need for the majority of manual and semi-automatic routine
11、 tests. One of the characteristics of suchsupervisory functions is that performance “thresholds” have to be set which, if exceeded, cause appropriate outputs toalert maintenance staff (for example, alarms, printouts, etc.). Maintenance staff should not only ensure that all relevantsupervisory functi
12、ons are invoked, but must regularly review the thresholds set to ensure that faults and problems will bedetected before service is unacceptably affected.Where the outputs to maintenance staff from SPC and digital exchanges indicate that a fault exists or issuspected, suitable action must be taken to
13、 localize the problem. Before seeking cooperation from the distantmaintenance centre, maintenance staff shall ensure that the problem is not within their own exchange. As examples,ATME No. 2 (Recommendation O.22 6) the facilities given in Recommendation O.11 7 and the internalself-diagnostic routine
14、s within the exchange should be used to this end.In view of the variety of different types of international exchange now in use and the differing facilities offeredby these exchanges, it is not possible to specify any particular periodicity for routine maintenance tests on signalling andswitching eq
15、uipment. The most appropriate periodicity must be established by the Administration concerned based onsuch factors as: the availability of staff; the technology of the exchange (for example, crossbar, Strowger, digital); the incidence of faults and problems within the exchange; the possible need for
16、 cooperation from distant maintenance centres; the periodicities recommended by the manufacturer of the exchange or equipment involved; the periodicities given in the Series Q Recommendations cited above.References1 CCITT Recommendation Manual testing, Vol. VI, Rec. Q.139.2 CCITT Recommendation Manu
17、al testing, Vol. VI, Rec. Q.163.2 Fascicle IV.1 - Rec. M.7323 CCITT Recommendation Testing and maintenance Overall tests of Signalling System No. 6, Vol. VI,Rec. Q.295.4 CCITT Recommendation Testing and maintenance, Vol. VI, Rec. Q.707.5 CCITT Recommendation Testing and maintenance, Vol. VI, Rec. Q.490.6 CCITT Recommendation CCITT automatic transmission measuring and signalling testing equipmentATME No. 2, Vol. IV, Rec. O.22.7 CCITT Recommendation Maintenance access lines, Vol. IV, Rec. O.11.
