1、CCITT FASCICLE 1V.L * 48b2.591 0505280 7 Recommendation M.251 MAINTENANCE FUNCTIONS TO BE IMPLEMENTED IN CCLTT-MML ) 1 Introduction This Recommendation identifies the maintenance functions to be controlled by means of the The CCI?T-MML (man-machine language) is intended to handle the functions requi
2、red to manage telecommunication systems, e.g. via a telecommunication management network (TMN) (see Recommenda- tion M.30). The man-machine interface (MMI) enables the exchange of information between users and systems encoded in MML. Interaction between the users and the controlled systems is based
3、on a repertoire of inputs, outputs, special This Recommendation deals with the specification and control of maintenance functions. The tests When defining MML-functions the tasks which need to be performed (jobs) are first identified, in order to The relationship between jobs, system functions and M
4、ML-functions is described in 5 1.2 of Recommenda- CCITT- M ML. actions and man-machine interaction mechanisms, including dialogue procedures. appropriate to particular maintenance functions remain as described in the relevant M-series Recommendations. derive system functions to be controlled. tion M
5、.250. For each system function, one or more MML-functions are derived. Each MML-function is then described using the “meta-language” defined in Recommendation 2.333 I, which permits the information structure to be defined in detail2). MML-functions do not necessarily represent the actual command str
6、ucture of any real implementation of the man-machine language. Each of the MML-functions could be implemented by providing a separate and distinctive command, or several MML-functions could be implemented using a single command. 2 System functions System functions can often be categorized and divide
7、d to break down a task and simplify the implementa- tion and control of such functions by the se of MML. An example showing the generalized functional architecture for a TMN is given in Figure 1/M.251. The MML will be implemented at the g reference point. Maintenance functions are related to the net
8、work element functions, as well as to the TMN general functions and TMN application functions as defined in Recommendation M.30. This complex of maintenance functions are to be described in two ways: i) ii) the rest (under study). on the basis of the “maintenance phases” of Recommendation M.20; 3 Sc
9、ope The term “maintenance” covers all aspects which have to do with failures, such as supervision, detection, The general concepts and philosophy are fully described in Recommendation M.20. The description of the maintenance functions on the basis of Recommendation M.20 has the advantage that genera
10、l descriptions of the various maintenance activities are obtained, valid for all network elements. In this case no separate descriptions for maintenance of “terminals”, “subscriber lines”, “exchanges”, “lines between exchanges”, etc. are necessary. localization, information, repair, etc. I) This Rec
11、ommendation is not yet complete, a number of items are for continuing studies. 2, For further studies, other methodologies than those described in 2.333 i may be considered. P -. Fascicle IV.l - Rec. M.251 205 CCITT FASCICLE IV.3 It m 4862593 0505283 9 li -I r- I I I I i TMN I I I I I I 1 I I I I I
12、I I I I I I I I I I I I I I 1 I I I I I I l I I I I I I l I I I I I l I I I I 1 I 1 I f X +6j?/ I I f Reference points: q Class of reference points between OS, M and NE functions f Class of workstation reference points g Class of workstation to user reference points x Class of reference points to ot
13、her networks, including other TMNs Function blocks: WSF Workstation function OSF Operations system function MF Mediation function NEF Network element function DCF Data communication function User FIGURE 1M.251 Generalized functional architecture (Diagram derived from Figure 2m.30) 4 Maintenance func
14、tions in the various maintenance phases The maintenance functions and their relationship to the maintenance phases, defined in 0 4 of Recommen- dation M.20, are listed in Table VM.251. 4.1 4.1.1 4.1.2 4.1.3 4.1.4 These maintenance functions have to be described; the status of these descriptions are
15、given below: Failure detection Continuous checking (see Note) Routine or periodic testing (see Note) Checking in live traffic (see Note) Checking in absence of live traffic (see Note) - 206 Fascicle IV.l - Rec. M.251 7 7 CCITT FASCICLE IV.1 ft 4862571 0505282 O TABLE UM.251 Maintenance phases Mainte
16、nance functions I I 1 Failure detection 1.1 Continuous checking 1.2 Routine or periodic testing 1.3 Checking in live traffic 1.4 Checking in absence of live traffic I 2 System protection I I I 3 Failure information 4 Failure localization 4.1 Assembling alarm messages 4.2 Request for failure informat
17、ion 4.3 TesVMeasurement 4.4 Setting of loops 5 Failure correction 6.1 Test/Measurement I 6 Verification 7 Restoration 7.1 Deblocking 4.2 4.3 4.4 4.4.1 4.4.2 4.4.3 4.4.4 4.5 4.6 4.6.1 4.7 4.7.1 Syst rz protection (under study) Failure information (under study; e.g. change of alarm levels) Failure loc
18、ation Assembling alarm messages (under study) Request for failure information (under study) Test/measurement (see Note) Setting of loops (under study) Failure correction (under study) Verijcation Test/measurement (see Note) Restoration Deblocking (under study) Note - As far as these functions are co
19、ntrolled by MML, they are covered by Annex A (whether the totality has been covered is still under study). 5 Other maintenance functions The maintenance functions in the areas of support of maintenance, of failure statistics and of preventive maintenance are under study. 6 Relation to Recommendation
20、 2.331 “Maintenance functions” In Recommendation 2.331 2, a list is given of maintenance functions. Items of that list which are - covered, in a general way, by this Recommendation are listed in Table 2lM.251. Fascicle IV.l - Rec. M.251 207 I CCITT FASCICLE 1V.L * 4862.591 0505283 2 -y I TABLE 2/M.2
21、51 Maintenance functions Maintenance of subscribers lines Testing one subscriber line and associated equipment Testing a group of subscriber lines and associated equipment Measuring one subscriber line and associated equipment Measuring a group of subscriber lines and associated equipment Blocking o
22、r unblocking a subscriber line for maintenance Observing or supervising subscriber lines and equipment Maintenance of circuits between exchanges and associated equipment Testing/Measuring one or group circuit(s) and associated equipment Observing and supervising circuit) and associated equipment Con
23、trol the status of one or group circuit(s) Analyzing maintenance data Administering and controlling maintenance reports Switching network maintenance Making test calls Initiating a call trace Holding faulty connections Testing and measuring peripheral equipment Testing and measuring switching units
24、Reducing service for low priority subscribers Setting up a connection via a specific path Supervising and measuring the Quality of Service Localizing faults in the speech path Providing access for traffic observations for maintenance Reporting alarms Recording switching unit status Control system ma
25、infenance Reporting system status Reporting alarms Localizing faults Testing on a functional basis after repair Initiating periodic testing operatipns Changing system configuration for maintenance Checking consistency of data Initiating restart Setting traps for programme faults tracing Changing mem
26、ory contents Memory dumping for maintenance purposes Controlling overload parameters Changing the criteria for degradation of service Reducing service for low-priority subscribers Covered in this Recommendation Yes Yes Yes Yes Under study Under study Yes Under study Under study Under study Under stu
27、dy Yes Yes Under study Yes Yes Under study Under study Yes Yes Under study Under study Under study Under study Under study YeS Yes Yes Under study Under study Under study Under study Under study Under study Under study Under study Under study : 208 Fascicle IV.l - Rec. M.251 CCITT FASCICLE IV-L * m
28、4862593 0505284 4 m 7 Description of maintenance functions in annexes to this Recommendation Annex A - General description of maintenance testdmeasurements Annex B - General description of failure information (under study) Annex C - Protection, restoration (under study) Annex D - Support of maintena
29、nce (under study). ANNEX A (to Recommendation M.251) General description of maintenance festsheasurements A.l Introduction One of the purposes of maintenance is to detect, localize and repair failures. Failures can be detected by means of different methods, .one of them being testdmeasurements. The
30、following description of tests/measurements is valid for all objects in a network. An object being defined for this purpose is anything in the network upon which a tedmeasurement can be performed. This description has been made according to Recommendation 2.332 3. A.2 Tests and measurements A.2.1 Do
31、cument A A.2.1.1 Introduction Maintenance tests and/or measurements may be performed on a demand and routine basis, according to the maintenance strategies. A.2.1.2 List of class B functions A.2.1.2.1 Testdmeasurements A.2.1.3 List of jobs A.2.1.3.1 Plan a routine test/measurement - The purpose of t
32、he job is to create (or change) a list of tests and test programmes containing ail of the data necessary for the test/measurements to be run successfully and to identify the objects on which the testdmeasurements are to be run. - The system is supposed to record all of the necessary data and create
33、(or change) required test/measurement sets. The user is supposed to introduce all the data needed. The complexity of the job may be high depending on the amount of data to be introduced. The frequency of the job is very low. The job is supposed to be performed at network and/or OMC level. - - - - A.
34、2.1.3.2 Dejne/change/delete the schedule of routine tests/measurements The purpose of the job is to schedule new (or change/delete existing) routine testdmeasurements depending on the number and types of objects to be tested/measured and the availibility of test equipment and test functions. The sys
35、tem is supposed to schedule (or change/delete) the requested tests/measurements according to the schedule input by the user. - - r ,- I Fascicle IV.l - Rec. M.251 2091 _1 - CCITT FASCICLE IV.3 * 4862593 0505285 6 I/ - The user is supposed to input the test/measurement types and related data (test/me
36、asurement sets information) and time parameters, such as start time, stop time, etc., in order to obtain the required schedule. - - - The complexity of the job is medium. The frequency of the job is low. The job is supposed to be performed at network and/or OMC level. Note - Change of the schedule m
37、ay be done by a combination of deleting the schedule in use and defining a new one. A.2.1.3.3 - A.2.1.3.5 - - - - - - A.2.1.3.6 - - - 210 Activate the execution of routine testsheasurements The purpose of the job is to perform a routine test/measuremerit according to a specified schedule. This allow
38、s the verification on a routine basis of the correct functioning of one or more objects. The system is supposed to perform the testdmeasurements according to the specified schedule. The results may be stored within the system for later analysis and/or output or routed to a designated hardcopy device
39、. The system may also be required to provide an output error message if it is unable to perform some of the requested testdmeasurements. The user may be required to input variables such as schedule identity, start time, stop time and a start point for a series of tests/measurements. The complexity o
40、f the job is low. The frequency of the job is medium, The job is supposed to be performed at network and/or OMC level. Stop/suspend the execution of a certain routine testheasurement The purpose of the job is to stop/suspend the execution of the test/measurement before the scheduled stop time. The s
41、ystem is supposed to stop/suspend the execution of the test/measurement according to the time data introduced by the user. The user is supposed to introduce the identity of the test measurement to be stopped/suspended and the time data of the actual stop/suspension. The complexity of the job is low.
42、 The frequency of the job is low. The job is supposed to be performed at network and/or OMC level. Activate the execution of on-demand testdmeasurements The purpose of the job is to perform on-demand tests/measurements on one or more objects in order to verify the correct functioning of the object(,
43、). The system is supposed to perform the actions requested on the specified objects as soon as possible. As many of the system parameters as possible should be system resident. The results may de displayed to the user, stored within the system and/or routed to hardcopy devices depending on the routi
44、ng control information. The system should output an error message (or code) if it is unable to perform the requested test/measurement. The user is supposed to input the type of the tedmeasurement and the identities of the objects to be tested/measured. The user may also have to input relevant parame
45、ters. These would normally be modifications of the system resident default values for a particular test/measurement execution (e.g., the number of times the test/measurement is retried). The complexity of the job is low, unless the user has to input a large number of parameters values. The frequency
46、 of the job is high. The job is supposed to be performed at network and/or OMC level. Delete one or more obsolete test/measurement data The purpose of the job is to delete the data related to a certain test/measurement component which are of no more interest. The system is supposed to delete the spe
47、cified data, providing the necessary safety strategies. The user is supposed to specify the identity of the data to be deleted. Fascicle IV.l - Rec. M.251 CCITT FASCICLE IV-L * W 4862571 0505286 8 W The complexity of the job is low. The frequency of the job is low. The job is supposed to be performe
48、d at network and/or OMC level. Retrieve relevant data of tesWmeasurements The purpose of the job is to retrieve information on the tests and/or measurements that are currently defined in the system. The system is supposed to provide to the user the requested information. The user is supposed to iden
49、tify the requested information. The complexity of the job is low. The frequency of the job is high. The job is supposed to be performed at network and/or OMC level. Retrieve the results of tests and/or of measurements already performed The purpose of the job is to retrieve the recorded results in order to examine them. The system is supposed to provide to the user the requested information. The user is supposed to introduce the identity of the items to be displayed. The complexity of the job is low. The frequency of the job is high. The job is s
