WO1997050209A1

WO1997050209A1 - A method for fault control of a telecommunications network and a telecommunications system

Info

Publication number: WO1997050209A1
Application number: PCT/FI1997/000414
Authority: WO
Inventors: Jukka Kivilahti; Jari Manninen; Maria Friman; Dan BJÖRKLÖF
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 1996-06-27
Filing date: 1997-06-26
Publication date: 1997-12-31
Also published as: FI962652A0; AU3264497A; FI104032B1; FI104032B; FI962652A

Abstract

The present invention relates to a method for processing fault and/or failure messages given automatically in a telecommunications network. The present invention relates further to a fault control unit arranged to receive all fault messages given in the telecommunications network and to analyze the state of the telecommunications network on basis of the given fault messages. The invention discloses a new type fault control method, by means of which the teleoperator receives in a quick and flexible manner reliable information about the condition of the telecommunications network and about the faults occurring in the telecommunications network.

Description

A METHOD FOR FAULT CONTROL OF A TELECOMMUNICATIONS NETWORK AND A TELECOMMUNICATIONS SYSTEM

Technical field of the invention

The present invention relates to a method for processing of automatically generated fault and/or failure messages caused by a faulty operation of a device operating and monitored in a network. In addition, the present invention relates to a fault control unit for a fault control of a telecommunications network.

Background of the invention

It is prior known that various fault and failure messages concerning the operation of a telecommunications network are given in the telecommunications network comprising a plurality of nodes, such as exchanges, and transfer paths, such as transmission connec¬ tions, arranged between the nodes for transmitting information therebetween. In practice the messages are given as a result of a fault operation of a network component. The transfer path comprises channeling groups, by means of which the data transfer capacity is increased, and transfer systems, which may include optical systems, radio systems and conventional copper cable systems. The main cause for the messages in the telecommu¬ nications network are the exchanges and the transmissions lines. A fault caused by an exchange results usually in a single fault message or in several subsequent fault messages of similar type, by means of which it is possible to conclude whether some actions are required to repair the fault or not. Contrary to that a fault caused by the transfer path causes in most cases two fault messages; from both exchanges between which the transfer path has been connected. In a typical case the transmission will also sent fault messages even in this case. Furthermore, the channeling devices in the transfer path may fail and cause fault messages, which in this case would be provided by both the exchanges and the other channeling devices connected to the failed channeling device.

Furthermore, a single telecommunications network may contain several different fault monitoring systems: for the monitoring of digital exchanges, analog exchanges and transmission lines. The problem is, however, that the fault messages given by the different fault monitoring systems are received, monitored and analyzed in different locations, most often in the exchanges, whereupon, in case of a fault, the service person has to enter the exchange through a computer or similar device of the given exchange, by means of which device the real cause for the problem is indicated, to be able to analyze the fault message from that exchange. A further problem is that in the described solution the operator responsive for the operation and the customer service cannot receive any more detailed information about the fault before the service person has visited the site and discovered the cause of the fault. In addition, in the known system there is a possibility for fault messa¬ ges which do not require immediate repair but do still result to a visit to the exchange. On the other hand, one and the same fault may lead to different types of fault messages and to messages from several different devices. The conventional system is not capable of filte¬ ring and interpreting the fault messages in a sufficiently effective manner.

Summary of the invention

An object of the present invention is to overcome the above disclosed problems. A more precise object of the present invention is to present a fault control method of a new type, by means of which the telecommunications operator will quickly and flexibly receive reliable information about the condition of the telecommunications network and about the faults or malfunctions occurring in the telecommunications network.

In addition, an object of the present invention is to present an efficient system for recei¬ ving and processing of fault messages given in the telecommunications network. Further¬ more, an object of the invention is to present a method and a system which is flexible and capable of operating in several different environments for the filtering of the fault messa¬ ges and for quickening and intensifying the service of the telecommunications network.

The claims are referred to in respect to the characterizing features of the present invention.

In accordance with the method of the present invention, in a telecommunications network comprising telephone exchanges connected to each other by transfer paths and in which telecommunications network a fault message is given on the basis of a faulty operation of and/or a failure detected in a component of the telecommunications network, a fault control is realized on grounds of the fault messages given in the telecommunications network. In general terms, the "telecommunications network" means in this application a fixed public telephone network or a mobile network, but it is also possible to corres¬ pondingly adapt the invention to other types of communications networks. The fault message from the transfer device may contain a code indicating an urgency class of the fault, data about the fault, a rack location at the device station, data about the group code relating to the main system and comprising the stations between which the signal transfer occurs, and a channeling level, a device type, an address data defined by a possible previous fault control system, such as the number and address of the service bus, time for the alarm/ fault, data about the acknowledgement of the fault message, acknowledgement location, data of a device of a further fault control system to which the alarming apparatus may possibly be connected to, a responsibility for the repair, an urgency required by the repair, a fault code and a fault text, eg. that "the incoming 8 Mbit/s signal is missing" .

According to the invention, each of the fault messages is received in a fault control unit which is connected to the telecommunications network. The processing of the fault messa¬ ges will preferably proceed in the following manner. Firstly, the received fault message is identified by studying whether a certain field is the same in the message as it is in the memory of the fault control system or not. Necessary rules required for the identification are preferably collected in the control system for the essential fault messages. When the event has been identified, the predetermined fields are sampled from the fault message, such as the type of the device, the location code and so on, in accordance with the prede¬ termined sampling rules. The rules define character strings limiting the sampled field. The event will be incorporated into the object corresponding the device on the basis of the sampled identifying data, said device corresponding to the device giving the message. An analysis relating to the identified event will be accomplished next. In this analysis it is possible to find the events relating to this given object, or other events and faults incor¬ porated into a further object relating to said object. On the basis of these checks the desired fault messages will be generated to be presented to the user or, if necessary, the previously generated fault messages will be deleted. According to a preferred embodiment the event will be correlated or combined with some of the previous fault messages.

It is further preferred to store the fault messages into an archive file, from which the original messages are available, if needed. However, it is the intention to identify all messages which are using a known message syntax. In the identification the received message is incorporated into a prenominated event in accordance with the contents of the fault message. The following proceedings of the fault message is based on the name of the event. The identification is performed by seeking key character strings from the fault message. It is also possible to seek for different key character strings from the lines of different messages. In case the identifying tests defined to a certain prenominated event will become true for the received message, it will be identified to be the same event in question. All messages following the defined message syntaxes will be identified. Unidenti- fied messages will be filtered and are not processed after the unsuccessful identification, but will, for example, remain in the archive for future proceedings.

Subsequent to the identifying of the event, essential data for that event is sampled from the received character string and is disposed to the attributes of the event, which include data indicating the state or the configuration of the network element. Such data of the fault message, which is important in view of the event in question, is stored into the event attri¬ butes, the value of which can be read later or can be utilized when analyzing the event in question or any other subsequent event. The sampling of the data from the received character string is preferably based on the location of the data in the character string and identifier characters or identifier character strings before and after the data.

In the analysis of the event it is for example possible to analyze the attributes of the event in question or any other event. In the analysis of the event it is possible to generate fault messages. It is also possible to find out that several conditions will become true simulta¬ neously. In addition, several conditions or events may be combined to form a certain fault message.

The following will also be presented in view of the analysis of an event or a fault messa¬ ge. If it is found in the analysis that none of the previous events relates to the processed event, the new event will be incorporated as it is into the fault message. In case the event situation is updated such that the cause thereof is most likely something else than what was the object of the fault of the previous fault message, the updated event situation will become incorporated into the new fault message. The events are recorded, a new fault/alarm is generated, in which all events are incorporated into, and the previous fault/ alarm is removed. If it is possible that some new events may be related to the event in question, it is possible to postpone the decision for subsequent operations.

An abbreviated message communication can be formed on grounds of the analysis, comprising at least data about the network component which caused the failure message, fault type, the location of the fault in the telecommunications network and the urgency level of the fault, and the message is transmitted in a predefined form to a predefined data means, such as to a mobile station of a certain service person. In this context it is notified that there are a plurality of other communications forms, by means of which the service person can be notified of the fault in the telecommunications network. Sending of an electronic mail message instead of the abbreviated message or in parallel with the abbre¬ viated message is mentioned as one example of such. The most significant advantages provided by the method according to the present invention are that it is open, cost effective, and that it provides open interfaces and a good usability of the system in a telecommunications network which contain network components provided by several different manufacturers. Moreover, by means of the present invention the operator will receive information about the operation of the different elements of the telecommunications network into a one location in a centralized manner.

In one preferred embodiment of the present invention the active events of the system are determined, die events are then correlated into correct fault messages, and only predeter¬ mined fault messages are announced to the user. An advantage of this embodiment is that the operator will not receive fault messages which would cause extraordinary and useless operations. The fault messages are preferably processed in an ASCII form.

In one preferred embodiment of the present invention the fault message is processed in the fault control unit in steps, such that a fault message event is firstly received and identified, whereby an information is received that one of the components operates in an undesirable manner. Thereafter the fields of the fault message are sampled and parsed, said field including more precise information about the fault, such as the urgency level of the fault and the location and type of the fault. The fault message event is subsequently incorpora¬ ted into one of the objects stored in the fault control unit on grounds of the field of the fault message, said objects preferably containing data about the network components, service personnel and the like matter, which are stored in a predetermined object database. The objects do not contain rules, but the rules for identifying, sampling and analyzing are rather stored separately, and there is no references between them and the object forms.

In addition, a fault control unit according to the present invention for the fault control of a telecommunications network having a plurality of nodes which are connected to each other by transfer paths, is arranged, in accordance with the invention, to receive in a centralized manner all fault messages given in the network independently from the fault monitoring system by means of which the fault message has been generated. The fault control unit further contains database means for storing predetermined data about the nodes belonging to the telecommunications network and about the transfer paths and the assembly therebet¬ ween. The database can be preferably formed by means of a computer, a software and a database file recorded into a recording means. In this case the performance of the system can be flexibly enhanced, if needed, by increasing the size of the database and by impro¬ ving the performance of the computer. According to the invention, the fault control unit further includes analyzing means for receiving and analyzing the fault messages given in the telecommunications network on grounds of the data stored in the database. Even ana¬ lyzing means can be realized by means of a computer and a software.

In one preferred embodiment of the present invention the fault control unit comprises an adapting system arranged between the control systems and the fault control unit of the telecommunications network. The adapting system uses preferably TCP/IP protocol (Transport Control Protocol/Internet Protocol).

Brief description of the drawings

In the following the invention will be described by means of the enclosed embodiments with reference to the enclosed drawing, in which

Figure 1 discloses schematically one telecommunications network provided with an fault control system in accordance with the present invention; and

Figure 2 discloses one channeling arrangement in one preferred telecommunications network according to the present invention.

Detailed description of preferred embodiments

Figure 1 discloses one telecommunications network 1 , which is provided with a fault control system according to the present invention. The fault control system may include monitoring systems 6, 7 and 8 intended for the monitoring of various components and parts. On the other hand, there may be a direct connection to the fault control system from each of the exchanges. For the monitoring of analog exchanges the monitoring system 6 is connected to the telecommunications network, from which system messages 10 are further transmitted to a fault control unit 2, as is evident from figure 1. Figure 1 further discloses the monitoring system 7 for the monitoring of digital exchanges of the telecommunications network connected to the telecommunications network 1 , by means of which the fault messages caused by the digital exchanges are transmitted to the fault control unit 2. Corresponding operations concerning transfer paths are in figure 1 accomplished by the system 8 intended for the monitoring of the transfer lines. The exemplifying fault control system of figure 1 further comprises an adapting system 5 arranged between the monito¬ ring systems 6, 7 and 8 and the fault control unit 2 connected to the telecommunications network 1. The adapting system is preferably arranged in connection with the fault control unit 2. In one application the fault messages are transmitted by means of a TCP/IP pro- tocol. Furthermore, it may be preferred to divide the adapting system 5 into portions in connection with each of the separate fault control systems (not shown) .

In figure 1 , a terminal 9 is also connected to the fault control unit 2, which device might be located in the premises of the telecommunications operator in different locations of the area of the telecommunications network 1. By means of the terminal 9 it is possible to receive and follow the information given by the fault control unit 2. In a preferred form the terminal 9 is a computer containing a central processing unit with processors and memories, a keypad, a display and other necessary external devices. By means of the terminal it is possible to supervise the model of various levels of the telecommunications network in a graphical or some other similar form, such as a telecommunications network covering an entire country, a network covering a city and even in a more detailed manner depending on the requirements of the particular situation. The wider the supervised telecommunications network model is, the less detailed data will be shown from the telecommunications network components. For example, when supervising a network for the entire country only the biggest, so called main exchanges, and the transfer connections therebetween are presented.

With a further reference to figure 1, the fault control unit 2 according to the present invention is described in further detail. Said unit comprises database means 3 for recor¬ ding the predetermined data about the nodes and transfer paths belonging to the telecom¬ munications network and the assembly therebetween. Figure 1 discloses one preferred data model in which various base data, such as data about the network configuration, a list about the devices, device locations and the relations between the devices, are recorded; this data is presented by block 3a. Block 3b presents the rules stored in the database concerning the urgency of the fault messages, the combining of the messages and other processing thereof. Block 3c presents the symbols, various block diagrams, maps and network models stored in the database, which are used for presenting the data at the terminal. In addition, by block 3d it is shown that a fault table has been stored into the database, from which it is possible to read the names of the faults, so that it is, for example, possible to bring the faults from the exchanges of different manufacturers having different names into conformity with each other. An exemplifying list which may be recorded from each of the components of the telecommunications network to the database into separate blocks thereof: list of the codes indicating the urgency of the fault, device data; device type, rack position, data about the group code relating to the terminal system, stations between which a signal is transferred, channeling level, possible address data defined by a previous system, computer data of another system which indicates the computer to which said device is connected to, list of the repair group of the fault, network model and logic according to the rules of which the fault messages will be handled.

Figure 1 shows also analysing means 4 which may comprise a memory device, such as a RAM memory, and a central processing device, for receiving and analysing the fault messages given in the telecommunications network 1 on grounds of the data stored into the database. The analysing means 4 are connected further to adapting system 5 and through that to the fault monitoring systems 6, 7 and 8 (figure 1). In addition, a direct connection is arranged from the analysing means 4 to the database means 3 for the reading of the data stored therein.

One preferred example of the operation of the system according to the present invention will be described in the following. A failure in operation of a switchyard has occurred in one digital exchange of the telecommunications network 1 , said failure being caused by a thunderstorm in that area. The exchange is not capable of recovering from the failure without the aid of a service person. It is noted in this connection that the urgency of the fault can be presented by at least five preferred manners: requires immediate action, requires action during the shift, can be handled in a normal order, a fault under repair which may cause a decrease in the service level, or a fault under repair which may cause temporary changes in the service. Furthermore, it is possible to represent the telecom¬ munications system by the monitoring terminal by means of block diagrams, icons and maps. In addition, by using appropriate colors it is possible to illustratively show the failed component, the urgency level of the fault and other similar data about the fault.

In case of a fault the digital fault control system 7 will detect it and gives a message 10, which includes the above listed data about the fault to the fault control unit 2 which receives the fault message. After this the fault message 10 is identified, and it is detected that the fault originates from an exchange. There might also be other fault messages arriving simultaneously to the fault control unit, for example caused by the same thunder¬ storm. By comparing or correlating the various messages it is possible to filter or parse the fault messages such that they cab eg. be set in an order according to the emergency level or the seriousness of the fault.

The formation of the fault message in connection with a signal fault may happen, for instance, in the following manner. Framing bits are transmitted in certain intervals in a transfer path extending between two telephone exchanges so as to form a synchronizing pattern to be monitored. The synchronizing pattern is defined in the ITU-T (International Telecommunication Union) standards. In case no synchronizing pattern is found, it will be notified in the exchange that the connection has broken down. The fault message, the form of which can be freely chosen or have a standard format, will be incorporated into a certain object by per se known methods used in the area of information technology. After this the measures caused by the fault message are defined on grounds of the object, i.e. a notice of the fault message will possibly be sent to the operator or to the service person, and in addition it is possible to program a notification to be given to the users of the telecommunications network which program will automatically notify them of the fault.

Referring now to figure 2 which discloses one example of a fault in the telecommunica¬ tions network, and the control thereof by means of an exemplifying system in accordance with the present invention. The figure discloses the channeling of a transfer line outgoing from an exchange 11 by means of channeling devices. By the channeling several simulta¬ neous transfer connections are combined in the same transfer line so as to increase the data transfer capacity. In figure 3 the four transfer conduits 2 Mbit/s each are channeled by the channeling device 2/8 to a speed of 8 Mbit/s. Furthermore, by channeling device 8/34 the four 8 Mbit/s are channeled to a speed of 34 Mbit/s and by a channeling device 34/140 further to a speed of 140 Mbit/s. Now, if some of the channeling devices, for instance 8/34, does not work, the channeling device 2/8 will notify that the incoming 8 Mbit/s signal is missing. Furthermore, the channeling device 34/140 will notify that the incoming 34 Mbit/s signal is missing from the subsystem, which has a certain code (four 34 Mbit/s signals will come to the 34/140 channeling device, whereby it can be concluded what signal is missing). The exchange 11 will also notify about the fault detected in the transfer connection. By combining the fault messages given by the components it is possible to locate the faulty channeling device. Thus the above described manner provides a possibili¬ ty to filter the messages coming from the same fault into one uniform informative mes¬ sage.

The following is disclosed as a summary of the solution according to the present inven¬ tion. The fault control system in accordance with the present invention, for instance NetExpertTM by QSI (Objective Systems Integrators) from USA, consists of software modules by means of which the system is controlled. The functions and modules of the software modules are: modelling of the telephone network or the parts thereof to the database, grouping of the exchange and transfer components in accordance with the functions thereof, rules for combining various messages meaning the same urgency, combining the fault messages of the same type into one single fault message for instance in a situation in which the devices of two manufacturers are giving different messages from the single and same fault. The software modules comprise also a module for making the above mentioned parts compatible. The advantages and object of the present invention are based on that by means of the invention it is possible to automatically filter or parse the fault messages, eg. messages indicating the same fault, whereby it is only the essential faults in view of the network which remain for the more precise processing.

The invention is not limited to concern the above exemplifying embodiments only, but many variations are available while remaining within the inventive idea defined by the claims.

Claims

1. Method for fault control in a telecommunications network (1) comprising nodes con¬ nected to each other by transfer paths, said method being based on fault messages given in said telecommunications network, in which telecommunications network a fault message is given on grounds of a faulty operation of and/or a failure detected in a component of the telecommunications network, wherein each of the fault messages is received in a fault control unit (2) which is connected to the telecommunications network (1); each of the received fault messages is identified in accordance with rules recorded in the fault control unit; the contents of each of the fault messages are analyzed; active events of the system are discovered; the events are correlated with the faults; and predetermined operations are accomplished in response to said analyzing and correlation to control and/or repair the fault and/or failure.

2. A method according to claim 1, characterized in that predetermined fault messages are announced to the user.

3. A method according to claim 1 or 2, characterized in that at least the network component which caused the fault message, the type of the fault, the location of the fault in the telecommunications network and the urgency level of the fault are defined on the basis of the analyzing of the conetnts of each of the receivcved messages.

4. A method according to any of the preceding claims 1 -3, characterized in that an abbreviated message is formed, said message comprising at least data about the net¬ work component which caused the fault message, about the type of the fault, about the location of the fault in the telecommunications network and about the urgency level of the fault; and that the abbreviated message is transmitted in a predetermined form to a predetermined data means, such as to a mobile station of a certain service person.

5. A method according to any of the preceding claims 1-4, characterized in that those objects which contain data about the generating rules of the fault messages, about the network components, about the service personnel and the like, are recorded to a prede¬ termined object data base.

6. A method according to any of the preceding claims 1-5, characterized in that the fault message is processed in the fault control unit (2) in the following manner: a fault message event is received and identified; the fields of the fault message are sampled and parsed; the fault message event is incorporated into one of the objects recorded in the fault control unit; and the fault message event is analyzed by comparing the event to the other received fault messages.

7. A method according to any of the preceding claims 1-6, characterized in that the fault messages are processed in an ASCII form.

8. A fault control unit (2) for a fault control of a telecommunications network (1) compri¬ sing a plurality of nodes which are connected to each other by transfer paths, wherein the fault control unit (2) is arranged to receive all fault messages given in the network; and the fault control unit comprises: database means (3) for recording predetermined data about the nodes and the transfer paths belonging to the telecommunications network and about the assembly therebetween; analysing means (4) for receiving and analysing the fault messages given in the telecom¬ munications network (1) on basis of the data recorded in the database; and means for discovering active events of the system and for correlating the active events with the faults.

9. A fault control unit according to claim 8, characterized by an adapting system (5) arranged between the monitoring systems (6,7,8) and the fault control unit of the tele¬ communications network (1).

10. A fault control unit according to claim 8 or 9, characterized in that the fault control unit (2) comprises a display device (9) for displaying the data describing the state of the telecommunications network in a predetermined format.

11. A fault control unit according to any of the preceding claims 8- 10, characte¬ rize d in that the fault control unit (2) is a computer comprising central processing unit and memory means.