KR20010054655A - Performance Monitoring and Control Scheme for SDH-based Physical Layer in Access Networks - Google Patents

Abstract

PURPOSE: A method for monitoring and controlling performance of a synchronous physical layer applied in an access network is provided to supply platform configuration that is a guiding principle in implement of performance monitoring device of synchronous physical layer. CONSTITUTION: Performance data of a performance monitoring device are initialized(S111). If installation of a board is detected(S112), an error accumulative value on signal is obtained by collecting performance data through performance accumulative registers of a physical layer chip every second(S113). If new board being installed is not detected any longer(S114), the first board is set(S121). If the first board exists, performance data processing is performed by obtaining other performance elements through the error accumulative value obtained(S124). A UAS(UnAvailable Second) is decided by using the performance elements obtained from the performance data processing(S125). A critical value every 15 seconds and a day is stored. If a value of performance elements accumulated in 15 second and a day is decided to over corresponding critical value, signal is decided to be a performance drop state(S127) and the performance elements accumulated in every 15 seconds and a day is reported to a network management device periodically(S128).

Description

Performance monitoring and control scheme of synchronous based physical layer applied to access network {Performance Monitoring and Control Scheme for SDH-based Physical Layer in Access Networks}

The present invention relates to a performance monitoring control method of a synchronous based physical layer applied to an access network. More specifically, the present invention defines performance elements to be monitored in a synchronous based physical layer applied to an access network. The present invention relates to a performance monitoring control method of collecting and processing them.

Conventionally, in order to monitor signal performance on a transmission path, a technique of displaying a parity error or a CRC method in units of bits is mainly used in terms of hardware. In addition, performance management was handled only on the assumption that performance data were collected and processed on the network side for performance monitoring.

Therefore, between hardware detection and network performance management, the hardware directly detects and accumulates accumulated errors by accessing the corresponding physical layer processing chip and monitors the performance factors required by the synchronous based physical layer based on the collected data. The technology to do it was required. In addition, ITU-T provides the signal configuration of the synchronous transmission mode and the performance monitoring overhead according to the performance of the synchronous physical layer, and presents only the definition of each performance factor and its reference plan for performance management. have.

Therefore, in order to measure performance on a transmission path, a medium in charge of a connection between a hardware manager for detecting a transmission error and a network manager in charge of performance management of a transmission network is required. In addition, if the hardware directly detects and accumulates the accumulated error through a hardware register or the like, the register is accessed and collected, and based on the collected data, the processing is performed to extract the performance factor required by the synchronous physical layer. Performance monitor is required.

In addition, for the performance of the synchronous physical layer, the ITU-T only provides the signal configuration of the synchronous transmission mode and the performance monitoring overhead accordingly, and proposes the definition of each performance factor and the reference plan accordingly for performance management. It does not mention specific implementation methods. It is difficult to be consistent in building performance monitors because the implementation depends on the device manufacturer.

Accordingly, the present invention has been made to solve the problems of the prior art, to provide a configuration of a platform that can be a guide in implementing a performance monitor of the synchronous physical layer.

1 is a performance monitoring procedure according to an embodiment of the present invention,

FIG. 2 is a flow chart of performance data processing shown in FIG. 1;

3 is a flow chart of the UAS determination shown in FIG. 1;

FIG. 4 is a flowchart for determining a threshold exceeded shown in FIG. 1;

FIG. 5 is a flowchart illustrating a signal degradation determination illustrated in FIG. 1;

6 is a window update flowchart for BER measurement shown in FIG. 5;

FIG. 7 is a procedure for confirming the current BER degree illustrated in FIG. 5;

8 is a procedure of determining whether or not a signal degradation occurs in FIG. 5;

FIG. 9 is a flow chart for performance periodic reporting shown in FIG. 1.

In order to achieve the above object, the performance monitoring control method of the synchronous-based physical layer applied to the access network according to the present invention includes a first step of initializing the performance monitoring and accessing the mounted boards to obtain an error accumulated value on a signal; A second step of obtaining values of other performance factors using the error cumulative value for each of the mounted boards, a third step of determining a UAS using the values of the performance factors, and a threshold for every 15 minutes and 1 day And storing the value of the performance factor accumulated for 15 minutes and 1 day exceeding the corresponding threshold, and transmitting the occurrence of the threshold exceedance for the performance factor to the network management apparatus. The error rate is calculated by using the method, and when the set signal degradation rate threshold is exceeded, it is determined that the signal degradation state is the fifth step, and every 15 minutes and 1 day. And a sixth step of periodically transmitting values of the accumulated performance factors to the network management apparatus.

Preferably, the second step includes a first sub-step of determining whether there is an error detected at the beginning of the present time point, an error is detected as a result of the determination of the first sub-step, and the detected error exceeds an SES threshold per second. A second substep of setting c_ES indicating an error in the current second and c_SES indicating an excessive occurrence of the error, and an error is detected as a result of the determination of the first substep, and the detected error is SES per second. And if the signal failure is occurring in the current second without exceeding the threshold, setting a c_ES indicating that there is an error in the current monitoring second, and storing a detection error as c_ERR.

More preferably, the third step may include a first sub-step of adding the c_ES and c_SES set in the second step to the current cumulative SES and the ES, and determining the UAS by using the cumulative SES and the ES. And a third sub-step for detecting the occurrence and release of the < RTI ID = 0.0 > and < / RTI > increasing the current ES, BBE performance cumulative value upon release of the UAS state in the second sub-step.

More preferably, the fifth step of determining the degraded signal performance state may include: a first sub-step for updating each sliding window for each BER, a second sub-step for checking the current BER degree, and the current BER; It is characterized in that it comprises a third sub-step to determine whether or not the occurrence / release of signal degradation by using this to report to the network management device.

According to the present invention, there is provided a computer-readable recording medium having recorded thereon a program for executing a performance monitoring control method of a synchronous-based physical layer applied to an access network.

Hereinafter, with reference to the accompanying drawings will be described in more detail the "performance monitoring control method of the synchronous-based physical layer applied to the access network" according to an embodiment of the present invention.

The definition of the performance monitoring controller of the synchronous based physical layer to be performed in the present invention is as follows.

BBE: Background Block Error, which is a cumulative value for bit errors that occur every second, and accumulates bit errors (BIP, CRC errors such as B1, B2, B3, etc.) that SES did not occur in that second.

ES: Errored Second, which is a cumulative value of seconds when one or more bit errors or one or more signal failures occur every second, but not in the UAS state.

SES: Severely Errored Second, a cumulative value of the number of seconds when a bit error that occurs every second exceeds the defined threshold, or when one or more signal failures occur.

UAS: UAS is declared when Unavailable Second, SES occurs for 10 seconds in a row. At this time, the cumulative value of UAS increases by 10, and the SES and ES decreases by 10. Deactivation of the UAS is declared when the non-SES state persists for 10 consecutive seconds. At this time, the UAS accumulation value is decreased by 10, and ES and bit errors occurring between 10 seconds are increased by the ES accumulation value and the BBE accumulation value, respectively.

BER: Bit Error Rate, bit error occurrence rate, 1.0 X 10 ^-5 , 10 ^-6 , 10 ^-7, etc.

1 is a flowchart illustrating a performance monitoring control method according to an embodiment of the present invention. 1 can be largely separated into three processes. That is, step S110 initializes the data of the performance monitor (S111), and if it is detected that the board is mounted (S112), the hardware is accessed every second to obtain a cumulative error value on the signal (S113). If there are more new boards (S114), the process proceeds to step S112 to further perform step S113. If there are no boards in step S112, the process proceeds to step S114 without proceeding to step S113.

In step S120, first, the first board is set (S121), and if there is a board (S122), the performance data processing step (S124) is performed to obtain values of other performance factors using the error accumulation value obtained in step S110. Next, the "UAS" is determined using the performance factor obtained through this process (S125). In addition, if the threshold value is stored for every 15 minutes and 1 day, and it is determined that the value of the performance factors accumulated for the current 15 minutes and 1 day exceeds the corresponding threshold (S126), the performance degradation (SD) state of the signal is determined ( S127) Finally, the performance factor values accumulated every 15 minutes and 1 day are periodically reported to the network management device (S128).

Step S130 is performed by polling the value obtained in step S120 every second. In addition, 12 and 22 of FIG. 1 determine the presence or absence of a board (or unit) in which a physical layer processing chip to be monitored is mounted in the current process. Let's do it. 15 and 23 are procedures to determine if there are more boards to be monitored now. 21 and 32 specify the first board to be monitored prior to beginning the performance data collection phase or the performance data processing phase.

The performance data initialization step of step S111 is performed in the following cases. First, it initializes the variables of all units used to collect performance data at system startup and restart. It also initializes the chip's registers, which directly collect performance factors. Second, when the unit is mounted, it initializes the performance data of the unit and initializes the registers of the chip mounted in the unit that directly collects the performance elements.

The performance data collection step of step S113 is directly collected every second through the performance accumulation register of the physical layer chip. The types of performance registers to be collected from the physical layer chip are as follows. First, the B1 error detects an error by using the B1 overhead byte in the reproduction section of the synchronous transmission mode and is driven by BIP-8 (Bit Interleaved Parity 8). Second, the B2 error is detected by using the B2 overhead byte in the multi-section of the synchronous transmission mode, and is driven by BIP-24 X N (N = 1, 4). Third, the B3 error is detected by using the B3 overhead byte among the VC4 (Virtual Container 4) path overhead in the synchronous transmission mode, and is driven by the BIP-8.

The performance data processing step of step S124 is a step of determining the presence or absence of ES, SES using the performance data collected every second. The detailed flow of its processing step is shown in FIG.

Referring to FIG. 2, in step S201, it is determined whether there is an error detected at the beginning of the present time. If there is an error, the process proceeds to S203, and if there is no error, the process proceeds to S202. S203 compares the error with the SES threshold per second, and proceeds to S210 and S211 if the threshold is exceeded, otherwise proceeds to S204. In step S202 and step S204, if it is determined whether a signal failure is occurring or occurred on the interval of the corresponding second, steps S205, S206, and S209 are performed to set ERR to zero. If no signal impairment has occurred in step S202 or S204, steps S207 and S208 are performed in the case of step S204, and S206 is performed in the case of S202.

In step S207, c_ES indicating that there is an error in the current monitoring seconds is set to one. In step S208, the detection error is stored as c_ERR. In step S210, c_ES indicating that there is an error in the current monitoring seconds and c_SES indicating that an error occurred too much are set. In step S206, there is no error currently occurring. In step S205 and step S209, the performance value detected by the occurrence of signal failure is set to zero.

FIG. 3 is a flowchart illustrating a determination (S125) of the UAS illustrated in FIG. 1. This UAS determination is performed using data on whether SES has occurred every second. Step S301 is a step of reading and determining c_SES which sets whether the error detected at this time is SES. If c_SES is set, the process proceeds to S302, otherwise, the process proceeds to S309. In step S302, it is determined whether a flag indicating that there is already a UAS state is set, which is called uas_flag. If uas_flag is set, the process proceeds to S308. Otherwise, the number of consecutive SES occurrences in S303 is accumulated in SES_consecutive_count and the process proceeds to S304. In step S304, it is determined whether SES_consecutive_count is 10, and in case of 10, it is determined that a UAS state has occurred, and the process for this is performed as in S306. On the other hand, if not 10, the process of S305 is performed.

In step S305, the values of c_SES and c_ES determined at the present time are added to the current cumulative SES and ES. It also initializes temp_ES and temp_BBE, which have arbitrary values for storing the accumulated values of BBEs and ESs that may occur in the UAS state. In step S306, since the UAS has occurred at this point in time, uas_flag is first set, and 10 is added to UAS, which is a cumulative stored value of the UAS state. To date, the accumulated SES and ES are subtracted from 10. In this case, 9 is subtracted because the ES and SES values detected at this point have not yet accumulated. It also initializes temp_ES, temp_BBE, and SES_consecutive_count. From this point in time, SES_consecutive_count is used to detect the release of the UAS state, and if it is not SES every second, the accumulated count is increased in S310.

In step S307, the UAS is reported to the external network management apparatus. In step S308, since the UAS is already in the state, the UAS value is accumulated and temp_ES, temp_BBE, and SES_consecutive_count are initialized. In step S309, it is performed when the current time is not in the SES state, and it is determined through uas_flag whether the current UAS state is in progress. If uas_flag is set, S310 is performed, otherwise S314 is performed. Step S310 is an intermediate procedure for determining the UAS state release. Here, temp_ES, temp_BBE, and SES_consecutive_count are accumulated, and the flow proceeds to step S311. In step S311, the SES_consecutive_count is compared to 10, and if it is 10, it is determined that the UAS state is released. If not, the process proceeds to S312.

In step S312, the uas_flag is first reset, the UAS accumulation value is subtracted from 9 as in the case of S306, the temp_ES and temp_BBE values which are temporarily accumulated in the ES and BBE accumulation values are increased, and the SES_consecutive_count is initialized. In step S313, the UAS status release is reported. Since S314 is not a UAS state and SES is not set at this time, the c_ES and c_BBE at the present time are increased to the ES and BBE accumulated values, and the temporary temp_ES, temp_BBE and SES_consecutive_count are initialized.

4 is a flowchart illustrating a process of determining a threshold exceeded shown in FIG. 1 (S126). This threshold determination is handled for the BBE, ES, and SES performance factors for 15 minutes / 1 day, and is reported only once per 15 minutes / 1 day when the threshold is exceeded. Although only shown for the 15 minute BBE in the present invention, the same method is used for the other elements. Referring to Figure 4 will be described the procedure for the threshold exceeded determination.

Step S401 is a step of determining whether a threshold exceeded has already occurred. If the threshold has already been exceeded, the threshold exceeding determination step is terminated. Otherwise, the flow advances to step S402. S402 compares the BBE value accumulated up to the present time and the BBE threshold, sets a flag indicating that the BBE threshold is exceeded in S403 when the threshold is exceeded, and reports a threshold exceeded alarm to the network management device. If the threshold is not exceeded, the threshold exceeding determination step is terminated.

FIG. 5 is a flowchart illustrating a process S127 of determining the signal degradation SD shown in FIG. 1. A sliding window technique is used to determine this signal degradation. This technique can be applied when the error probability distribution is Poisson distribution. Currently, ITU-T's error processing method is divided into Poisson distribution and burst error processing method. However, these two methods tend to be a trade-off, and the principle is to determine signal degradation through processing by Poisson distribution. . Table 1 lists the reference tables for the request time for determining the degradation in signal performance according to the sliding window technique.

BER Occur release 1.0E-5 1 sec 10 sec 1.0E-6 10 sec 100 sec 1.0E-7 100 sec 1000 sec 1.0E-8 1000 sec 10000 sec 1.0E-9 10000 sec 100000 sec

In order to measure BER, we need 10 windows for each BER, one variable that can display one total, and one temporary total variable for temporary use. In order to determine signal degradation, three procedures as illustrated in FIG. 5 are required.

First, in each window update procedure (S501) for determining signal degradation, the temporary sum is updated in a window for each BER by using a bit error collected every second. This BER window update step is shown in detail in the flowchart of FIG.

First, step S601 is a step of increasing the unit time t. For convenience of calculation, after 10 ⁶ seconds (S608), it becomes 1 second through steps S609 and S601.

In step S602, the current c_ERR (t) is applied to the variable T ₀ (t).

Next, while changing the variable i from 1 to 4 (S603 and S604), it is determined whether the t module 10 ^i-1 (t% 10 ^i-1 ) is 0 (S605). If the result of step S605 is YES, the process proceeds to S606 and returns to step S604. If the result of step S605 is NO, the process proceeds to step S607 and returns to step S604.

In step S606, n _i (t) = (t / 10 ^i-1 )% 10, T _i (t) = T _i (t-1) -x (n _i (t)) + T _i-1 (t) , x (n _i (t)) = t _i-1 (t)), and the variable i is increased by one. In step S607, the operation T _i (t) = T _i (t-1) is performed, and the variable i is increased by one.

If i is greater than 4 in step S604, the flow advances to step S608 to determine whether t is 10 ⁶ . If t is 10 ⁶ , after initializing t to 0 (S609), the sliding window update process is terminated. If t is not 10 ⁶ , the sliding window update process is immediately terminated.

Here, the variable i distinguishes the window of each BER by the integer of 1-4. The present value n _i (t) is the counter value of the i th window and has an integer value of 0 to 9. x refers to the value of the oldest accumulated window, and the update of the new accumulated value is made to the value of the nth x window. T _i (t) is the sum reflecting the current state of the bit error detected every second.

Next, to determine the signal degradation is performed the current BER degree confirmation procedure (S502). An internal detailed flow chart of this current BER degree verification procedure is shown in FIG.

Referring to FIG. 7, in S701, i is initialized to 0 as a reference for an initial BER degree value. If i is greater than 4 in step S702, it is outside the range to be measured, and as in step S705, the current BER degree is regarded as ^10-11 . On the other hand, if i is less than or equal to 4, the process proceeds to S703 and compares the threshold SD_THR _i for each BER degree corresponding to each BER degree and the current cumulative value T _i . If the current cumulative value exceeds the threshold, as in S706, the degree of BER at the present time is determined as 10 ^{− (i + 5)} . If the current cumulative value is lower than the threshold, i is increased as in step S704 and step S702 is executed again.

Finally, to determine the signal degradation, it is determined whether the signal degradation occurs using the current BER degree and the signal degradation reference threshold (S503). First, in step S801, it is determined whether a signal deterioration state is currently occurring. If it is currently occurring, the process proceeds to S802, otherwise, the process proceeds to S805. In step S802, the current signal degree of BER is compared with a signal degradation reference threshold which determines that the signal degradation state is deteriorated. At this time, if the current BER degree is smaller than the reference corresponding to 1/100 times the set standard, since the signal degradation is canceled, the signal degradation flag is reset as in step S803, and the signal performance is transmitted to the network management apparatus. Report the deterioration state (S804). On the other hand, if the current degree of BER is large, the determination of whether or not signal degradation occurs.

Step S805 compares the current BER degree with the signal deterioration determination reference value because the current signal deterioration state has not occurred. If the current BER is large, it means that a signal degradation has occurred. Therefore, a signal degradation flag is set (S806), and a signal degradation occurrence is reported to the network management apparatus (S807). On the other hand, in the case where the current BER degree is small in step S805, determination of whether or not a signal performance degradation occurs is finished.

FIG. 9 is a detailed flowchart of the performance periodic reporting step S128 shown in FIG. 1. The performance periodic report includes a 15 minute periodic report (S902) and a daily periodic report (S906). In the case of 15 minutes, the report is performed every 00/15/30/45 minutes (S901). In the case of 1 day, the report is performed every 00: 00 (S905). In addition, the ITU-T recommendation recommends that performance data store the performance of the previous 15 minutes and 1 day in addition to the current performance. For this purpose, steps S904 and S909 are performed.

According to this, in the case of 15 minutes, the previous 15 data is stored, and in the case of 1 day, one previous day performance data is accumulated. The accumulation of such historical data is performed when the performance value is not 0 (S903 and S907). After the 15-minute and 1-day periodic reporting, the current 15-minute / 1-day stored value and the threshold exceeded indication flag value are initialized (S908 and S910).

While the invention has been described above based on the preferred embodiments thereof, these embodiments are intended to illustrate rather than limit the invention. It will be apparent to those skilled in the art that various changes, modifications, or adjustments to the above embodiments can be made without departing from the spirit of the invention. Therefore, the protection scope of the present invention will be limited only by the appended claims, and should be construed as including all such changes, modifications or adjustments.

As described above, according to the present invention, the ITU-T provides only the signal configuration of the synchronous transmission mode and the performance monitoring overhead according to the performance of the synchronous physical layer, and defines each performance element for performance management. It does not refer to specific implementation methods, only the proposals and the corresponding standards. That is, since the concrete realization device depends on the manufacturer, it is difficult to be consistent in producing the performance monitor. Therefore, the present invention has the effect of configuring a platform that can be a guide in implementing the performance monitor of the synchronous physical layer.

The present invention can be applied to all transmission devices accommodating the synchronous PHY layer by serving as a medium connecting the hardware for directly extracting the performance of the synchronous PHY layer and the performance management unit of the network.

Claims (5)

A first step of initializing the performance monitoring and accessing the mounted boards to obtain an error accumulation value on a signal; A second step of obtaining values of other performance factors using the error accumulation value for each of the mounted boards; A third step of determining a UAS using the values of the performance factor, A fourth step of storing a threshold value for every 15 minutes and 1 day, and transmitting the occurrence of the threshold exceedance for this performance factor to the network management device when the values of the performance factors accumulated for the current 15 minutes and 1 day exceed the respective thresholds; A fifth step of calculating an error rate by using the accumulated error value obtained every second and determining that the signal degradation state is exceeded when the threshold of occurrence of signal degradation is exceeded, and And a sixth step of delivering the accumulated values of the performance factor to a network management device periodically for every 15 minutes and 1 day. The method of claim 1, wherein the second step, A first substep of determining whether there is an error detected at the beginning of the present time point; As a result of the determination of the first sub-step, when an error is detected and the detected error exceeds the SES threshold per second, the second element is set to c_ES indicating that there is an error in the current second and c_SES indicating that an error has occurred excessively. step, If an error is detected as the determination result of the first sub-step, and the detected error does not exceed the SES threshold per second and a signal failure occurs in the current second, set c_ES indicating that there is an error in the current monitoring second and set a detection error. and a third sub-step of storing as c_ERR. The method for controlling performance monitoring of a synchronous based physical layer applied to an access network. The method of claim 2, wherein the third step, A first sub-step of adding c_ES and c_SES set in the second step to the current cumulative SES and ES, A second sub-step of determining a UAS using the cumulative SES and the ES to detect occurrence and release of a UAS state, and And a third substep of increasing this to the current ES and BBE performance cumulative value when the UAS state is released in the second substep. According to any one of claims 1 to 3, wherein the signal deterioration state determination step of the fifth step, A first substep of updating each sliding window for each BER; A second substep of identifying the current degree of BER, and And a third sub-step of determining whether or not to deteriorate / release signal performance using the current BER and report it to a network management device. On your computer, A first step of initializing the performance monitoring and accessing the mounted boards to obtain an error accumulation value on a signal; A second step of obtaining values of other performance factors using the error accumulation value for each of the mounted boards; A third step of determining a UAS using the values of the performance factor, A fourth step of storing a threshold value for every 15 minutes and 1 day, and transmitting the occurrence of the threshold exceedance for this performance factor to the network management device when the values of the performance factors accumulated for the current 15 minutes and 1 day exceed the respective thresholds; A fifth step of calculating an error rate by using the accumulated error value obtained every second and determining that the signal degradation state is exceeded when the threshold of occurrence of signal degradation is exceeded, and A program for executing the performance monitoring control method of the synchronous based physical layer applied to the access network including the sixth step of delivering the accumulated performance factor values to the network management device periodically every 15 minutes and 1 day. Computer-readable recording media.