KR100298235B1 - Permanent Virtual Connection Availability parameter extracting method based on the accounting records generated in the data networks providing PVC services - Google Patents

Abstract

The present invention relates to a method of extracting quality of service availability (virtual line availability, average time between service failures, average recovery time) using a charging record in a communication network providing a permanent virtual connection (PVC) service. Compensates for the shortcomings of the prior art, which require long-term network observation and quality measurement, high measurement equipment and operation costs for measuring the available quality values, and also facilitates easy system implementation, low implementation costs and the use of all virtual circuits in the network. The use of information ensures representativeness of network quality.

Description

Permanent Virtual Connection Availability parameter extracting method based on the accounting records generated in the data networks providing PVC services}

The present invention relates to a method for extracting service availability quality values using accounting records generated in a communication network providing a permanent virtual connection (PVC) service. To extract availability (Permanent Virtual Circuit Availability, hereinafter PVCA), mean time between service outages (MTBSO) and mean time to repair (MTTR) The present invention relates to a method of extracting a service availability quality value from a communication network using a billing record.

The billing record generated from the network providing the PVC service is used for all the virtual lines connected to the network, using the network service time of the virtual line, information of which party is connected to it, and for some reason when the virtual line terminates abruptly during the service. Information about whether the call was released and its recovery information, how long the call was normally served, and how long the service failure time occurred, and in particular the originating / receiving port number and the logical channel number of the exchange. Numner, hereinafter referred to as LCN). The exchange used in the communication network stores the above charging information for all virtual circuits connected to the communication network in a standardized format, and then transmits the data to the network management system (hereinafter referred to as NMS) of the corresponding communication network. Save it to The transmission of billing information to the NMS varies from network to network, but typically takes place 12 times a day, twice a day.

At present, the information and communication service market is expanding more than ever with the creation of various information and communication services and the development of devices with improved performance. Accordingly, each information and communication service provider is also keen to provide cheaper, faster and higher quality services. There is a competition. At this time, the information communication service providers have an exclusive advantage in the information communication service market, and an important factor for generating high profits is the guarantee of the quality of the communication service provided to the users of the information communication service. Rather than simply guaranteeing the quality of the telecommunications services, the telecommunications service users are provided with the reliability, transparency and objectivity of the quality of service offered by the telecommunications service providers that have contracted with them, and the corresponding compensation method when the quality of service is less than expected. Has emerged as a concern for competitive telecommunications service providers.

In line with the trend of the ICT market, the International Telecommunication Union (ITU-Telecommunication, ITU-T), the Frame Relay Forum, and the ATM Forum are also very close to this problem. It is showing interest and is undertaking standardization work. Although the items defined as information communication service quality by each standardization body are various, the service availability quality items described in the present invention are quality items that are common to each standardization organization. In the present invention, only the method of extracting these items is described. do.

Among the International Organization for Standardization, ITU-T specifically defines and describes service availability quality items in the ITU-T Recommendations. The service availability quality items defined by ITU-T include PVCA, MTBSO and MTTR. In ITU-T, these availability quality items are actually measured using a test line of the type shown in FIG. The ITU-T method monitors the protocol flow of the measurement control unit (DTE-A; 13), the device under test (DTE-B; 14), and the test line in order to measure the availability quality items for a particular virtual circuit. Although measuring equipment such as a measuring instrument 16 is required, and the service availability quality item for a test line section is measured using the measuring apparatus, the measuring control device 13 and the measured object in the test environment as shown in FIG. Synchronous matching between the devices 14 must be premised. However, it is virtually impossible to synchronize synchronization for all virtual circuits existing in the communication network. In other words, the ITU-T method is expensive for the measurement equipment required for the measurement when measuring several test lines, and there are technical difficulties for synchronization of the measurement equipment.

Figure 1 of the ITU-T periodically generates a test frame and calculates each quality of service item as an average of data or samples obtained through the test. Since the method of ITU-T is measured by using some test lines, it is difficult to see the test results as representative values of the service availability quality of the entire network, and at least 7 test intervals are required to measure PVCA items. It is recommended that the test data be carried out so that the number of test data per day is very small so that the PVCA estimate can be seen after at least six months to one year of testing. However, this means that if a service contract is made for a specific service item between a user of the communication service and the provider, the service quality item may be compensated after 6 months or a year after the compensation system is generally formed on a monthly basis. Should be considered less likely to contract with such service providers. It would obviously be a huge blow to the telecommunications service provider.

Another problem in measuring service availability quality items described in the ITU-T is that it is difficult to read for a test virtual circuit how long the virtual circuit has been normally served. In other words, if a contract between the telecommunication service provider and the telecommunication service user is used for a service use time, the telecommunication service provider should provide the service normally without service breakdown for 24 hours a day. However, if a service failure occurs in the middle, it is difficult to determine whether there is a service failure and to read the service failure time by the method defined in the ITU-T. In other words, to read that a particular test virtual circuit segment is in an unusable state (not normally served), the method of ITU-T is called a Frame Loss Ratio (FLR), which represents the percentage of frames lost in the network. Residually Frame Errored Ratio (hereinafter referred to as RFER), which calculates the number of frames in which a frame transmitted from the calling party arrives at the called party normally but an error occurs in the user information field of the received frame. Three parameters are used: Extra Frame Rate (EFR), which indicates the rate of unexpected frames observed over time. If the above three parameters are above a certain threshold, the test virtual circuit reads that the service has been normally provided for a certain time, and if any of the three parameters does not meet the threshold value, the test virtual circuit can Read that the service was not provided normally. However, the ITU-T does not yet define these threshold values clearly, and is continuing to study them. In addition, among the above parameters, RFER and EFR require advanced measuring equipment, and even if such measuring equipment is used, it is very difficult to actually measure the value. Therefore, the method of measuring service availability described in ITU-T is not available until now. This is less.

Telecom service providers, which are active in the ICT market and are fiercely competing to occupy the telecommunications service market, are expected to acquire subscribers and generate high profits by providing service users with service levels / degrees on the quality of service they receive. Can be. Therefore, faster service quality item definitions and method extraction methods must be developed to achieve their goals.

The present invention is to overcome the problems of FIG. 1 of the prior art, the service availability by using the billing data generated in the communication network, without using a separate measuring equipment in a communication network providing a permanent virtual connection (PVC) service By extracting (virtual line availability, average time between service failures and average recovery time), representativeness of data communication network quality is ensured, and the system is easy to implement and low cost to implement. An object of the present invention is to provide a method of extracting service availability using billing data.

According to FIG. 1 of the related art, long-term quality measurement and observation of a communication network are required for measuring service availability, and for this, high measurement equipment and operation costs have to be taken. However, the present invention provides a method for extracting PVCA, MTTR, and MTBSO using billing data that includes information on all virtual circuits generated in a communication network providing a PVC service in order to compensate for the above disadvantages and achieve a desired purpose.

1 is a configuration diagram of a communication network providing a permanent virtual connection service,

2 is a block diagram of a charging record to which the service availability quality value extraction method is applied in a communication network providing a permanent virtual connection (PVC) service of the present invention;

3 is a flow chart of quality value extraction according to the present invention;

<Description of the symbols for the main parts of the drawings>

21: Field indicating whether the virtual line is connected

22: From / To address where virtual line is set

23: Cause of release and diagnostic code

24: virtual line time set / restored and time when virtual line is released

25: Virtual line recovery field

26: caller ID number

27: Call channel channel number

The present invention is effective when a communication network providing a PVC service generates a charging record composed of fields having the following information. That is, the switches 11 constructed in the communication network 15 providing the PVC service of FIG. 1 are fields 21 indicating whether the virtual circuit of FIG. 2 is connected to all virtual circuits 12 existing in the communication network, Field indicating the originating and receiving address of the virtual line 22, the cause of the call when the virtual line is released, the diagnostic code 23, the service start and end time 24 of the call, and whether the call was restored if the call was released. 25), specifically, information such as the originating / receiving node identification number 26 with which the virtual circuits are interconnected, the originating / receiving port number 27 of the exchanger, and the logical channel number 28 used are stored in the charging record, and It transmits the information of the billing record to the network management system of the communication network twice a day for 12 hours. The billing data of the data communication network (HiNET) currently being operated by KT includes such information.

In FIG. 2, a field indicating whether a virtual line is connected / repaired is a recordType_last (21) and a recordType_first (25), and when recordType_last is 1, the previously connected virtual line is released due to some cause. The calling / called address is represented by callingAddress (22) and calledAddress (22), and the cause of the virtual circuit release and the diagnostic code are represented by clearCause (23) and diagnosticCode (23). clearCause and diagnosticCode classify the cause of virtual circuit release into network side and user side, and this classification is possible by the information stored in the database where the network identified and diagnosed the cause of call release. The start / end time of the virtual line is startTime (24) and endTime (24), where startTime is the time when the virtual line is connected and endTime is the time when the virtual line is finished.

Now look at the service availability extraction method using the charging record of Figure 2 to achieve the present invention. First of all, the PVC service must maintain the virtual line connection for the contracted service time between the network service provider and the user, unless a special situation occurs due to its characteristics. However, the virtual line can be terminated for various reasons, in which case the communication network generates a charging record. Using the generated charging record, it is possible to extract the quality of service availability for the service for a certain period of time for a specific PVC. In other words, if recordType_last recorded in the charging record (hereinafter referred to as Rb) is 1, the virtual circuit is released. Therefore, the cause of the virtual circuit release is analyzed by analyzing the clearCause and diagnosticCode codes. If the cause of the virtual line release is caused by the network side, the number of service failures is increased by 1 to indicate that the interruption of the PVC service is caused by the network cause. If the call is not released by the cause of the network side, it is not the responsibility of the network service provider and does not consider the number of occurrences of service failures for the release call, even if the call was released by any cause. Since the release of the virtual line by the cause of the communication network is automatically recovered when the cause is removed from the communication network, in this case, another charging record (hereinafter referred to as Rf) is generated in the communication network. As described above, when the charging record Rb and the charging record Rf are generated, a service failure time can be extracted using the startTime and endTime of these charging records Rb and Rf. That is, the service failure time is a value obtained by subtracting the endTime of the charging record Rb from the startTime of the charging record Rf. In this way, the service availability quality value may be calculated using the extracted number of service failures and the service failure time.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a flowchart illustrating a service availability quality value extraction method according to the present invention.

First, to extract the service availability, the charging record (Rb) generated for a certain period of time should be collected and analyzed (step 31). From the generated charging record field, a field recordType_last indicating whether a virtual line shown in FIG. 2 is connected or not is extracted. If the field recordType_last value extracted in step 31 is 1, this indicates that the connected virtual line has been released for some reason (step 32).

After determining that the virtual line has been released, the cause of the release of the virtual line and the diagnostic codes (clearCause and diagnosticCode) stored in the communication network are analyzed (step 33) to determine the cause of the virtual line release (step 34). If the cause of the virtual line release is due to the cause of the communication network (step 35), the number of service failure occurrence counts is increased by one (step 36). If not, do not increase the number of service failures. This is because the service availability quality item is to grasp the extent to which the communication network can normally provide the service to the service user, and thus calculates it by focusing on the problems caused by the causes of the communication network.

When a new charging record is generated, it is analyzed whether or not it is a charging record having recovery information of the previously released virtual line (step 37). In step 37, a billing record (Rf) having a calling / calling node identification number, a calling / calling port number, a calling / calling address, and a logical channel number equal to Rb among billing records generated after network recovery, and having recordType_first of 1 in the record field (Rf). ). If the charging record is a charging record having the recovery information of the previously released virtual line, the time interval of the two charging records is calculated as a startTime of Rf = startTime-endTime of Rb is calculated (step 38). The price can be regarded as a service failure time, and is calculated by subtracting the end of the charge record Rb from the start time of the generated charge record Rf. At this time, the time when the subscriber fails to provide the communication service due to the release of the virtual line due to the subscriber's cause, such as when the terminal power is turned off, is excluded from the calculation and is regarded as an exceptional service failure time (step 39). In step 39, in the case of call release by network-side cause, TIME becomes the service outage time of the PVC, otherwise TIME becomes the excluded outage time.

When the service outage time, the number of service failures, and the excluded outage time calculated during the interval time are extracted, the virtual line availability for the analysis target PVC ( Permanent Virtual Circuit Availability (PVCA), Mean Time Between Service Outages (MTBSO) and Mean Time To Repair (MTTR) can be calculated (step 40). That is, PVCA, MTBSO, MTTR calculation is as follows.

PVCA = (interval time-excluded outage time-outage time) / (interval time-excluded outage time) × 100,

If count ≥ 1, MTBSO = (interval time-excluded outage time-outage time) / count

Else if count = 0, MTBSO = 0

If count ≥ 1, MTTR = (outage time) / count.

Else if count = 0, MTTR = 0

Where PVCA is calculated as (Total Service Time-Exception Service Failure Time-Total Service Failure Time) / (Total Service Time-Exception Service Failure Time) * 100, and MTBSO indicates that if the number of service failures is greater than or equal to 1, Calculated as (Total Service Time-Exception Service Failure Time-Service Failure Time) / (Total Service Failure Occurrences), and MTBSO is 0 when the service failure occurs zero. The MTTR is calculated as (total service failure time) / (total service failure occurrence) when the number of service failure occurrences is greater than or equal to 1, and MTTR is 0 when the service failure occurrence number is zero.

Accordingly, the service availability quality value extraction method for providing a permanent virtual connection (PVC) service according to the present invention does not need to install a separate measurement equipment for calculating the service availability, and the operation cost for the measurement equipment is increased. By using the billing record as described above, service availability can be extracted without the need for additional hardware, and the service calculated by using the billing record indicating the usage characteristics for all PVC connected to the communication network. Availability values can be reliable.

Claims (7)

In the service availability quality value extraction method for providing a permanent virtual connection (PVC) service in a communication network, Field indicating whether or not the virtual line is generated in the communication network, originating / receiving address, cause and diagnosis code of the virtual line, start / end time of the virtual line, originating / terminating node identification number, originating / terminating port number, originating / Setting a charging record having an incoming logical channel number; Analyzing the cause of the virtual line release and the diagnostic code among the fields of the charging record generated when the virtual line is released for a particular PVC; Checking whether the virtual line is cut through the cause of release and analysis of a diagnostic code by the analysis step; Calculating a frequency of occurrence of service failure only when the virtual line is released due to the communication network side; By using the field indicating whether the virtual line is connected, the calling / called address, the start / end time of the virtual line, the calling / called node identification number, the called / called port number, and the called / called logical channel number. Finding a restored virtual line charging record; Extracting a service failure time using a field indicating a start / end time of a virtual line between billing records; And, The service availability is a service availability quality value extraction method comprising the step of calculating the quality value of the virtual line availability, the average time between service failures, and the average recovery time. The method of claim 1, In the step of extracting the service failure time, the service failure time is one of the billing record fields generated when the virtual line is established and released by the cause of the communication network. A service availability quality value extraction method comprising calculating the difference between two time points using the end time of a call. The method of claim 1, And calculating an exceptional service interruption time due to a subscriber-side cause in the step of finding the service failure time. The method of claim 1, If the service failure time, the number of service failure occurrences, the exception service failure time calculated during a predetermined period in the step of extracting the service failure time is extracted, Computing virtual line availability (PVCA), mean time between service failures (MTBSO) and mean recovery time (MTTR) for the analysis target PVC. The method of claim 4, wherein The MTBSO extracts a service availability quality value when the number of service failures is greater than or equal to 1, and calculates (total service time-exception service failure time-service failure time) / (total service failure occurrences). Way. The method of claim 4, wherein The PVCA is a service availability quality value extraction method, characterized in that calculating the (total service time-exception service failure time-total service failure time) / (total service time-exception service failure time) * 100. The method of claim 4, wherein And the MTTR is calculated as (total service failure time) / (total service failure occurrence number) when the number of service failure occurrences is greater than or equal to one.