1、INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECT0 R OF ITU M.1539 (03/99) SERIES M: TMN AND NETWORK MAINTENANCE: INTERNATIONAL TRANSMISSION SYSTEMS, TELEPHONE CIRCUITS, TELEGRAPHY, FACSIMILE AND LEASED CIRCUITS Designations and information exchange Management of the
2、 grade of network maintenance services at the maintenance service customer contact point (MSCC) ITU-T Recommendation M. 1539 (Previously CCIlT Recommendation) STD-ITU-T RECMN M.1537-ENGL 3997 W 4862573 Obb0773 245 ITU-T M-SERIES RECOMMENDATIONS TMN AND NETWORK MAINTENANCE: INTERNATIONAL TRANSMISSION
3、 SYSTEMS, TELEPHONE CIRCUITS, TELEGRAPHY, FACSIMILE AND LEASED CIRCUITS Introduction and general principles of maintenance and maintenance organization International transmission systems M.300-M.559 International telephone circuits M.560-M.759 M.10-M.299 Common channel signalling systems Internation
4、al telegraph systems and phototelegraph transmission M. 760-M. 799 M.800-M.899 International leased group and supergroup links International leased circuits Mobile telecommunication systems and services International public telephone network International data transmission systems Designations and i
5、nformation exchange International transport network Telecommunications management network Integrated services digital networks Common channel signalling systems M.900-M.999 M. 1000-M. 1 O99 M.11 00-M. I199 M.1200-M.1299 M. 1300-M. 1399 M.1400-MA999 M.2000-M.2999 M.3000-M.3599 M.3600-M.3999 M.4000-M.
6、4999 For further details, please refer to ITU-T List of Recommendations. STD-ITU-T RECMN M-1539-ENGL 1999 m 4Bb2571 Obb0774 181 m ITU-T RECOMMENDATION M.1539 MANAGEMENT OF THE GRADE OF NETWORK MAINTENANCE SERVICES AT THE MAINTENANCE SERVICE CUSTOMER CONTACT POINT (MSCC) Summary This Recommendation p
7、rovides the guidelines for the management of the Grade Of network Maintenance Services (GOMS) at the Maintenance Service Customer Contact point (MSCC). For any Maintenance Service (MS), the MSCC is a conceptual point at which a Maintenance Service Provider (MSP) and each of its Maintenance Service C
8、ustomers (MSCs) can interact in order to provide, use, operate, measure, retain, manage, invoice, etc., the MS concerned according to the GOMS which has been established in a contract or in an informal agreement. In this Recommendation, the following subjects are covered: 4 b) the GOMS general aspec
9、ts, from the point of view of an MSC and the point of view of an MSP requirements; the fundamental QOS criteria, methodologies, performance parameters, their indices and measurements, adopted for any MS and its Maintenance Service Elements (MSEs), including the associated set of maintenance processe
10、s and their specific procedures; the description of a consistent set of standardized Operational Procedures Selection for the management, achievement and improvement of the GOMS (OPSG) and the relevant main performance pararnetershndices, which must ensure that for any MS and its individual network
11、and service elements or any other support function i.e. Operations, Administration Maintenance and Provisioning (OAM the fundamental QOS criteria, methodologies, performance parameters, their indices and measurements, adopted for any MS and its Maintenance Service Elements (MSEs), including the asso
12、ciated set of maintenance processes and their specific procedures; the description of a consistent set of standardized Operational Procedures Selection for the GOMS management (OPSG) and the relevant main performance parametershndices, which must ensure that for any MS and its individual network and
13、 service elements or any other support function i.e. Operations, Administration, Maintenance and Provisioning (OAM b) any specific OAM performance indices for any specific MS. cl 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this
14、 text, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; all users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent e
15、dition of the Recommendations listed below. A list of the currently valid ITU-T Recommendations is regularly published. - - ITU-T Recommendation E.440 (1 996), Customer satisfaction point. ITU-T Recommendation E.800 (1 994), Terms and dejnitions related to quality of sewice and performnnce including
16、 dependability. Recommendation M.1539 (03/99) I - STD-ITU-T RECMN ImL539-ENGL L999 ITU-T Recommendation G.82 1 (1 996), Error performance of an international digital connection operating at a bit rate below the primary rate and forming part of an integrated services digital network. ITU-T Recommenda
17、tion G.826 (1 996), Error performance parameters and objectives for international, constant bit rate digital paths at or above the primary rate. ITU-T Recommendation 1.61 O (1 999), B-ISDN operation and maintenance principles and functions. ITU-T Recommendation M.60 (1 993), Maintenance terminology
18、and definitions. ITU-T Recommendation M. 1230 (1 996), Method to improve the management of operations and maintenance processes in the international telephone network. ITU-T Recommendation M. 1530 (1 999), Network maintenance information. ITU-T Recommendation M. 1535 (1 996), Principles for maintena
19、nce information to be exchanged at customer contact point (MICC) . ITU-T Recommendation M. 1537 (1997), DeJinition of maintenance information to be exchanged at customer contact point (MICC). ITU-T Recommendation 4.822 (1994), Stage I, stage 2 and stage 3 description for the Q3 interface - Performan
20、ce management. CCITT Recommendation X.733 (1 992) I ISOIIEC 1 O 164-4: 1992, Information technology - Open Systems Interconnection - Systems Management: Alarm reporting function. ITU-T Recommendation X.739 (1993) I ISOIEC 10164-1 1 : 1994, Information technology - Open Systems Interconnection - Syst
21、ems kanagement: Metric object and attributes. 3 Abbreviations and acronyms This Recommendation uses the following abbreviations: ATM Asynchronous Transfer Mode ATM PVC BER Bit Error Rate EI ES Errored Seconds GOMS Grade Of Maintenance Service ISDN Integrated Services Digital Network Asynchronous Tra
22、nsfer Mode Permanent Virtual Circuit maintenance service Element performance Index IS0 International Organization for Standardization LCS Leased Circuit Service MICC MS Maintenance Service MS/GOMS MSAV Maintenance Service Availability MSC Maintenance Service Customer MSCC Maintenance Information to
23、be exchanged at the Customer Contact point The GOMS related to a specific MS Maintenance Service Customer Contact point , MSE Maintenance Service Element - 3 Recommendation M.1539 (03199) STD-ITU-T RECMN MmL537-ENGL 1977 48b259L Obb0781 31% MSP Maintenance Service Provider OAM b) achieve, maintain o
24、r improve when required the GOMS of an MS; cl allow an MSC to make, for the same type of MS offered by different MSPs, an objective comparison between each of the GOMS offered by individual MSPs. For an efficient management of the agreed GOMS it is necessary to establish an adequate Operational Proc
25、edures Selection (OPSG) which contains a well-defined amount of basic processes and relevant procedures among which the fundamentals are: 1) the collection of all pararnetersprocedures included in any of the identified MS process and relevant performance indices measurements and limits thresholds wh
26、ich define the proper functioning state; the recording of all data in order to monitor and analyse the trends of all performance indices concerned; reporting of data, that is, any information as needed which will be exchanged between the MSC and the MSP in order to jointly assess the achievement or
27、the improvement of the agreed GOMS. Considering the above OPSG objectives. it is of primary importance for both MSC and MSP to set up and manage any internal and external interface procedure as needed. The main benefits that an MSP will derive through the management of the GOMS are the following: 2)
28、 3) optimization of the internal organizational structure to reply properly to any MSC for any MS, appropriate choice and systematic update of its own performance indices which requirement for a specific MS; are used to monitor and manage every MSE, its processes and relevant procedures. As regards
29、the relationship involved between an MSC and an MSP for the management of the GOMS, this implies a systematic and objective monitoring, the measurement of all identified performance indices of any offered MS and its individual MSE concerned. Therefore, from an operational point of view the best way
30、to proceed for both an MSC and an MSP is to follow-up and update all standardized operational procedures once the overall agreed GOMS has been signed in a contract or in an informal agreement. Recommendation M.1539 (03/99) 5 STDeITU-T RECMN M-153q-ENGL 3999 48b2591 Obb0784 020 Figure 1 shows the ref
31、erence model for the management of the GOMS. A specified GOMS is agreed between an MSC and an MSP regarding an MS provided by the MSP at the MSCC. Within the MSP, in order to manage the agreed GOMS, an OPSG may or may not be determined as part of the agreement. The OPSG consists of MSEs associated i
32、ndividually with their own performance index (EI). Each MSE consists of several processes associated with performance indices. Each process consists of several procedures associated with performance procedure indices. These procedures produce MSE specific functions. Each performance index is monitor
33、ed through its conformance to a specified limit. Appropriate procedures shall be regularly and carefully applied to maintain the agreed GOMS. 6 Recommendation M.1539 (03/99) STDaITU-T RECMN M-1539-ENGL 1999 48b2591 Obb0785 Tb7 x . OPSGAi I I I I I I I I I I I I I I I I I I I I I I I I I I I l I I I
34、I I I I I I I I l I I I I I I I I I I I l I I I I I l I I MSPT . I I I I I I I I I I I I I l l I I I I I l l I I I l I I I I l I I I l l I I I I I I l I I I l I I Procedurei, a Procedurei, . I MSC MS GOMS MSP OPSG MSE PI PrI EI PrIi, a Prliaa I MSPM I I . OPSGZi i 2 . OPSGJi I PROCESSia a I Pliaa I
35、. I- PROCESSia PIi, t, TO40901 O-! (from A to Z) (from a to z) (from Ai to Zi) (from F to T) (from Ai to Zi) (from a to w) (from a to k) (from a to m) (from a to w) Figure 1M.1539 - Reference model for the management of the GOMS Recommendation M.1539 (03/99) 7 STD-ITU-T RECMN Mo1539-ENGL 1999 48b259
36、1 Ob60786 9T3 7 GOMS states and concepts of “acceptable“ and “unacceptable“ In order to achieve a common understanding between an MSC and an MSP and clearly identifi the actual GOMS state, two distinct states are defined: “acceptable“ and unacceptable. The following concepts are used: 1) Acceptable
37、state - The GOMS fulfils the overall objective as agreed in the contract or in the informal agreement. This means a situation better than or equal to the agreed limit. 2) Unacceptable state - The GOMS does not comply with the overall objective as agreed in the contract or in the informal agreement.
38、Figure 2 shows the GOMS states and the limit. ACCEPTABLE UNACCEPTABLE I I I I GOMS limit 0409020-9a Figure 2M.1539 - GOMS states 8 The main MSC expectations for any MS to which it will subscribe are the following: Maintenance Service Customer (MSC) expectations for the GOMS optimization of the perfo
39、rmance and cost of the MS; clear definition of all advantages obtainable, through a common understanding of any general technical and non-technical issues related to the MS; simple verification of the achievement of the foreseen advantages and consequently to have the possibility to make an easy sel
40、ection of the MSP(s); systematic review and easy comparison between the expected and the achieved quality of an MS; agreed GOMS. This implies the definition of specific grade states and associated parameters for which appropriate performance limits or thresholds must be specified in a contract or in
41、 an informal agreement of the MS concerned; more reliable quality data of the involved MS, that is, more transparent exchange of information with the MSP, and as a consequence a more objective utilization of any “ad hoc“ programme finalized to restore or improve the agreed GOMS of the MS concerned;
42、prompt, easy, reliable and secure access to the MSCC to carry out any type of activity regarding the GOMS (e.g. to notifj and follow up any quality problem impacting the MS, obtaidexchange any type of current or past inforrnatioddata on GOMS); prompt and efficient coordination by all MSPs involved i
43、n its MS to carry out any activity to achieve the agreed GOMS objective or any specified quality target as deemed necessary. MSC requirements for the GOMS Once the MSC expectations for a specific MS become actual clauses and they are specified and signed in a contract or in an informal agreement wit
44、h an MSP, these expectations represent its effective/agreed requirements. In general, these MSC requirements can be either independent of the type of MS or its characteristics which are usually related to the relevant telecommunications 8 Recommendation M.1539 (03/99) STDmITU-T RECMN M-3539-ENGL L99
45、9 m q86259L Ob60787 83T purposes (i.e. communication service required), or they can be strictly dependent on this MS type or these characteristics. 9.1 The main customers requirements which are independent of the type or the characteristics of an MS are as follows: MSC requirements and goals indepen
46、dent of the characteristics of the MS a) Specifieuagreed degree of accessibility, exchange of information and security to all MS capabilities and any network and service supporting/interfacing facility at the MSCC. For example: contact time: 24 hours/day over 365 days per year; different means of co
47、mmunication to access the MSCC (e.g. telephone, facsimile, email); continuous, reliable and full access to browse through all historical and current MS/GOMS data, including the ability to insert, change, or remove controls, or to interact with any network element in any way and the ability to insert
48、, modi6, or delete GOMS reference data and the relevant MSEs performance indices thresholds or any other parameter. Examples of the above information are: MS start date; number and type of the contract, start, end and duration of all MS/GOMS unavailable/unacceptable states including relevant causes
49、or any other impairment or outage with the relevant localization details. b) Specifieuagreed way how to access the efficiency of the MSP for all needed MS, in terms no shift for the Ready For Maintenance Service/GOMS date (RFMS) when it is contractually agreed; time to restore the GOMS/MS, in case the GOMS is in an unacceptable state and also the MS is unavailable, not exceeding a certain limit, in order to ensure that the overall Maintenance Service Availability (MSAV)8 is retained within the agreed contractual value; specified/agreed time of intervention in the pre
