A method for generating the Cn value by mapping the Basic Mapping Specification (GMP) within an Optical Data Transmission Network (OTN).

Abstract

The present invention relates to the field of communications. A method for generating a Cn value by a generic mapping procedure (GMP) mapping in an optical transport network (OTN), the method comprising: in each cycle, counting rate information statistical values of an opposite-end signal and a local low-order ODU signal, respectively; starting from the second cycle, producing a difference value in each cycle; comparing the difference of each cycle and a filter result of a previous cycle, to obtain a filter difference; amplifying the filter difference to a pre-configured filter coefficient times to acquire an adjustment value; accumulating the adjustment value of each cycle and the adjustment value of the previous cycle to acquire an integral value; when the integral value of one cycle is greater than 255, the filter value is 1, and the Cn value of the cycle = nominal Cn value + filter value; otherwise, the filter value is 0, and the Cn value of the cycle = nominal Cn value. According to the present invention, the circuit consumes a small amount of resource, and the circuit structure will not change due to changes to the mapping object, thus reducing jittering of the Cn value.

Description

A method for generating Cn values ​​in OTN GMP mapping Technical Field This invention relates to the field of communications, and more specifically to a method for generating Cn values ​​in OTN using GMP mapping. Background Technology In recent years, OTN (Optical Transport Network) technology has gradually become one of the mainstream technologies in the field of optical communication. In OTN services, mapping low-order ODU (Optical Channel Data Unit) into high-order ODU is a key technology. Currently, most methods for generating Cn values ​​using GMP (Generic Mapping Procedure) mapping determine a coarse Cn value (number of n-bit client data entities) by analyzing the waterline position of the FIFO (First Input First Output) controller in the data path. However, as new client signals emerge, the adjustment range of GMP mapping—that is, the rate difference between client and server signals—will increase. Generating Cn values ​​with one-byte precision requires increasingly larger FIFO specifications, leading to greater circuit resource consumption. Furthermore, changes in the mapped object significantly alter the circuit structure, inevitably resulting in substantial jitter in the generated Cn value. Summary of the Invention To address the shortcomings of existing technologies, the present invention aims to provide a method for generating Cn values ​​through GMP mapping in OTN. The Cn value has a precision within one byte, consumes minimal circuit resources, and its circuit structure remains unchanged regardless of variations in the mapping object, thus reducing the reduction in Cn value. jitter. To achieve the above objectives, this invention employs a method for generating Cn values ​​in OTN GMP mapping, comprising the following steps: S1. In each cycle, the rate information statistics of the peer low-order ODU signal and the rate information statistics of the local low-order ODU signal are statistically analyzed respectively; starting from the second cycle, a difference value is generated for each cycle, wherein the difference value is the difference between the rate information statistics of the local low-order ODU signal and the rate information statistics of the peer low-order ODU signal in the previous cycle; S2. The difference value of each cycle is subjected to low-pass filtering processing, i.e. Starting from the second cycle, the difference value of each cycle is subtracted from the filtering result of the previous cycle to obtain the filtering difference value; the filtering difference value is amplified to a pre-configured multiple of the filtering coefficient to obtain the adjustment value; the adjustment value of each cycle is accumulated with the adjustment value of the previous cycle to obtain the integral value; when the integral value of a cycle is greater than 255, the filtering value is 1, otherwise, the filtering value is 0; S3. When the filtering value of a cycle is 1, the Cn value of that cycle = nominal Cn value + filtering value; when the filtering value of a cycle is 0, the Cn value of that cycle = nominal Cn value. Based on the above technical solution, each cycle is a fixed period of the same time, and the fixed period depends on the rate information of the higher-order ODU mapped by GMP. Based on the above technical solution, the comparison standard between the rate information of the peer low-order ODU signal and the rate information of the local low-order ODU signal is consistent. Based on the above technical solution, in step S2, the adjustment value is accumulated through an integral circuit to obtain the integral value. Based on the above technical solution, in S2, the adjustment value of the first cycle is 0. Based on the above technical solution, in step S2, the filter value is determined by a decision circuit, which is used to determine whether the integral value of each cycle is greater than 255. Based on the above technical solution, in step S2, the pre-configured filter coefficients The range is 1 to 255. The lower the filter coefficient, the smoother the filtering result; the higher the filter coefficient, the faster the filtering tracking speed. Based on the above technical solution, when the OTN starts powering on or switches services, a high filtering coefficient is configured; when the OTN is tracking for a long time, a low filtering coefficient is configured. The beneficial effects of this invention are as follows: First, the difference between the rate information statistics of the local low-order ODU signal and the rate information statistics of the remote low-order ODU signal is obtained. Then, low-pass filtering is performed. Since the smoothing process is applied to the signal with the difference, the total amount of data remains unchanged, reducing the jitter of the Cn value. Simultaneously, the algorithm for obtaining the Cn value simplifies the entire calculation, ensuring the precision of the Cn value is within one byte. This minimizes circuit resource consumption, and the circuit structure remains unchanged regardless of changes in the mapping object. Attached Figure Description Figure 1 is a flowchart of the method for generating Cn values ​​in OTN according to the present invention; Figure 2 is a schematic diagram of low-pass filtering processing according to an embodiment of the present invention. Detailed Implementation The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. As shown in Figure 1, the method for generating Cn values ​​in GMP mapping in OTN according to the present invention includes the following steps: S1. Within each cycle, extract the rate information value of the peer low-order ODU signal, and simultaneously generate the rate information value of the standard low-order ODU signal locally. Furthermore, within each cycle, statistically analyze the rate information of both the peer and local low-order ODU signals. Starting from the second cycle, generate a difference value for each cycle. This difference value is the difference between the statistical value of the local low-order ODU signal and the statistical value of the peer low-order ODU signal in the previous cycle. In other words, the difference value for the first cycle is generated in the second cycle, and so on. No difference was generated in one cycle. Specifically, each period is a fixed period of the same duration. This fixed period depends on the rate information of the higher-order ODUs mapped by GMP. Specifically, according to protocol G.709, for higher-order ODUs, such as ODU4 and ODU5, they correspond to different periods in the protocol. The comparison standard between the rate information of the peer-end low-order ODU signal and the local low-order ODU signal is consistent, so as to accurately reflect the rate difference between the local and peer-end low-order ODU signals within a fixed time period. Within the same system time, the number of bytes transmitted by the peer-end low-order ODU signal and the local low-order ODU signal is consistent for both the local and peer ends, thus ensuring that the measurement mechanisms for the peer and local ends are consistent. S2. As shown in Figure 2, the difference value of each cycle is subjected to low-pass filtering. That is, starting from the second cycle, the difference value X[n] generated in each cycle is subtracted from the filtering result Y[n] of the previous cycle to obtain the filtered difference value. The filtered difference for each cycle is amplified by a pre-configured multiple of the filter coefficient to obtain the adjustment value. In Figure 2, coeff represents the filter coefficient, and Adj indicates the adjustment by amplifying to a pre-configured multiple of the filter coefficient. The pre-configured filter coefficient ranges from 1 to 255. A filter coefficient closer to 1 represents a lower value, resulting in smoother filtering results; a filter coefficient closer to 255 represents a higher value, resulting in faster filtering and tracking speed. Different filter coefficients can meet filtering requirements under different conditions. When the OTN starts powering on or switching services, rapid adjustment is needed, requiring a high filter coefficient, which results in relatively large fluctuations in the Cn value. When the OTN is tracking for a long period, a stable adjustment mode is needed, requiring a low filter coefficient, resulting in a relatively stable Cn value. The Cn value obtained in this embodiment is from long-term tracking. The adjustment value of each cycle is summed with the adjustment value of the previous cycle to obtain the integral value. An integrator circuit `sum` is used to count the accumulation of the adjustment values, starting with the first cycle's... The adjustment value is 0. The filter value is then determined by a decision circuit quantizer. This decision circuit provides a decision value based on the result of the integrator circuit, used to determine whether the integral value of each cycle is greater than 255. This decision value is the filter value for that cycle. Specifically, when the integral value of a cycle is greater than 255, the filter value is 1; otherwise, the filter value is 0. S3. Starting from the second cycle, generate the Cn value for each cycle based on the filter value. Specifically, when the filter value for a cycle is 1, the Cn value for that cycle = nominal Cn value + filter value; when the filter value for a cycle is 0, the Cn value for that cycle = nominal Cn value. This invention is not limited to the embodiments described above. Those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications are also considered within the scope of protection of this invention. Contents not described in detail in this specification are prior art known to those skilled in the art.

Claims

Page 1 of 2 Claims 1. Method for generating Cn values ​​by creating a GMP map within a type of OTN with the following characteristics and steps: S1. Within each circuit, statistical data is recorded for both the minimum ODU signal speed statistics at the destination and the minimum ODU signal speed statistics at the local level, respectively. Starting from the second circuit, each circuit generates a differential value. This differential is the difference in the data transmission speed statistics of the signal, which is obtained by subtracting the data transmission speed statistics of the local minimum ODU signal from the data transmission speed statistics of the destination minimum ODU signal in the previous circuit. S2. Manage the basic frequency filtering for the differential in each circuit: Starting from the second circuit, subtract the frequency filtering effect of the previous circuit from the differential in each circuit to obtain the frequency filtering differential. Amplify the frequency filtering differential to be several times the predetermined frequency filtering coefficient to obtain an adjustment value. Add the frequency filtering differential in each circuit to the adjustment value in each previous circuit, accumulating it as a cumulative value. When the cumulative value in one circuit exceeds 255, the filter value becomes 1; otherwise, the frequency filter value is 0. S3.When the filter value in any circuit is 1, the Cn value in this circuit = the specified Cn value + the filter value. When the filter value in any circuit is 0, the Cn value in this circuit = the specified Cn value.

2. The method of generating the Cn value by creating a GMP map within the OTN, as mentioned in point 1 of the rights request, has the following characteristics: Each circuit mentioned is a permanent circuit with equal time. The permanent circuit depends on the speed rate message of the advanced ODU in the GMP mapping.

3. The method of generating the Cn value by creating a GMP map within the OTN, as mentioned in point 2 of the rights request, has the following characteristics: This standard for comparing the minimum ODU signal speed at the terminal and the minimum ODU signal speed at the local level must be the same.

4. The method for generating the Cn value by creating a GMP map within the OTN, as mentioned in point 1 of the rights request, has the following characteristics: within S2, as mentioned, the total score is obtained by combining the improvement values ​​of one circuit, accumulating points on page 2 of 2 pages.

5. The method for generating the Cn value by creating a GMP map within the OTN, as mentioned in point 4 of the rights request, has the following characteristics: in S2, as mentioned, the improvement value in the first circuit is 0. 6.The method for generating the Cn value by creating a GMP map within the OTN, as described in point 1 of the rights request, is as follows: Located in S2, the frequency filtering value is determined by the decision circuit. The decision circuit is used to analyze whether the total value in each circuit will be higher than 255 or not.

7. The method for generating the Cn value by creating a GMP map within the OTN, as described in point 1 of the rights request, is as follows: The predefined frequency filtering coefficient range is 1-255. The lower the coefficient, the smoother the frequency filtering; the higher the coefficient, the faster the frequency filtering tracking speed.

8. The method for generating the Cn value by creating a GMP map within the OTN, as described in point 7 of the rights request, is as follows: When the OTN starts switching on the power or switching services, the filtering coefficient is set high. When the OTN is being tracked, the frequency filtering coefficient is set low.