CN1235373C - Method of triggering re-consultation mechanism based on point-to-point communication protocol in asynchronous transfer mode - Google Patents

Abstract

The invention discloses a method for triggering a renegotiation mechanism based on an asynchronous transfer mode (ATM) point-to-point communication protocol (PPPOA). The CPU at the PPPOA server end realizes synchronous sending and receiving information with the PPPOA terminal according to the time period of the created timer; the PPPOA server creates a timer and further includes: a. setting the base time value and the constant value of calculating the timer length respectively; b. calling PPPOA The underlying time function of the system generates a random value for calculating the length of the timer; c. Calculate the length of the timer according to the base time value set in step a, the constant value and the random value obtained in step b. The method not only solves the situation that the CPU occupancy rate of the server is too high and the resource of the PPPOA system is unavailable, but also solves the CPU idle period of the server, so that the PPPOA system can be fully utilized. It provides a guarantee for the normal operation of the PPPOA system.

Description

Method for triggering renegotiation mechanism of point-to-point communication protocol based on asynchronous transfer mode

technical field

The invention relates to the access technology in the field of data communication, in particular to a method for timer triggering the renegotiation mechanism of the point-to-point communication protocol (PPPOA) based on the asynchronous transfer mode (ATM).

Background technique

PPPOA is an ATM-based point-to-point communication protocol (Point to Point Protocol OverATM). The terminal directly initiates a PPP call. After receiving the information from the terminal, the device performs encapsulation processing to form an ATM cell stream, and the ATM cell stream is sent to the server. Complete a series of PPP access such as authorization, authentication, IP address allocation and billing. After the PPPOA system is connected, a series of information processing processes are completed.

The actual application of the PPPOA system network is shown in Figure 1. Figure 1 is a schematic diagram of a typical PPPOA system application network. It is composed of access equipment and edge service node (ESR). Among them, RTU is the PPPOA terminal; ESR is the PPPOA server. When the PPPOA system information processing process adopts the renegotiation mechanism, the user sends or receives information to the ADSL server-side access device through the RTU, and the ADSL server-side access device transmits the information to the ESR to complete the entire information sending and receiving process.

The renegotiation mechanism of the PPPOA system is triggered by a timer. The steps of the renegotiation mechanism are: a. The PPPOA terminal uses batch processing to send or receive information; b. The PPPOA server creates a timer, so that the CPU of the PPPOA server and the PPPOA terminal realize Synchronously receive or send information; c, complete PPPOA information sending and receiving. In the above process, since the length of the timer is fixed, the PPPOA system has no way to determine the length of the timer time according to the amount of information processed by the PPPOA terminal, which leads to two problems: on the one hand, if the PPPOA terminal receives Or when sending a large amount of information, that is, when a large number of PPPOA terminals use the renegotiation mechanism to send or receive information at the same time, a large number of timers will be created so that the CPU of the server and each PPPOA terminal will be in different time intervals. Synchronously process the information from the corresponding PPPOA terminal through batch processing. Once some of the timers expire, a large amount of information will start renegotiation at the same time. The time when the PPPOA terminal receives or sends information is not affected by the timing of the PPPOA server. Time control of the server, so that the PPPOA server receives or sends too much information in the same period of time, resulting in the situation that the CPU usage rate on the PPPOA server is too high at a certain moment, and the PPPOA system resources are unavailable. When the situation is serious, it will Cause the whole PPPOA system to be paralyzed; on the other hand, when the PPPOA terminal receives or sends too little information, the time set by the fixed-length timer is too long, and the PPPOA server CPU will be in an idle state for a certain period of time, making the PPPOA system resources cannot be fully applied.

It can be seen that the fixed length of the timer is the main cause of the problem. For example, when a fixed-length timer is used to trigger the renegotiation mechanism, as shown in Figure 2, when 2000 permanent virtual connections (PVCs) are configured on the edge service node, if the timer time is 3 seconds, the service processing board The CPU occupancy rate of the unit (SPU) is 100% in the third second. In this case, the CPU occupancy rate of the SPU is too high and the resources are unavailable.

Contents of the invention

In view of this, the main purpose of the present invention is to provide a method for triggering the PPPOA renegotiation mechanism, which solves the situation that the PPPOA server CPU occupancy rate is too high, the system resources are unavailable, and the PPPOA server CPU has an idle period, so that the PPPOA system can be fully use.

In order to achieve the above object, the present invention provides a method for triggering a renegotiation mechanism based on Asynchronous Transfer Mode (ATM) Point-to-Point Communication Protocol (PPPOA). timer, then the CPU at the PPPOA server end realizes synchronous sending and receiving information with the PPPOA terminal according to the time period of the created timer; the PPPOA server creates a timer and further includes:

a. Set the base time value and constant value for calculating the timer length respectively;

b. Call the underlying time function of the PPPOA system to generate a random value for calculating the length of the timer;

c. The result obtained by multiplying the constant value set in step a and the random value obtained in step b, and the base time value set in step a is used as the timer length to create a timer.

In the above scheme, the length of the timer can be a random value from 10 seconds to 140 seconds; the base time is set according to the unit time value of the currently used time chip; the constant is set according to the minimum estimated value of the currently transmitted information amount .

It can be seen from the above scheme that the timer triggering method of the PPPOA renegotiation mechanism provided by the present invention changes the fixed-length timer triggering the PPPOA renegotiation mechanism into a timer of random length. Set the time length of the timer according to the amount of information received or sent by the PPPOA device, and the time set by the timer will not cause timeout or idleness under any circumstances. It not only solves the problem that the PPPOA system resources are unavailable when the CPU occupancy rate of the PPPOA server is too high, but also solves the problem that the CPU of the PPPOA server has idle periods, so that the PPPOA system resources can be fully utilized. The invention provides a guarantee for the good and safe operation of the whole PPPOA system.

Description of drawings

Figure 1 is a schematic diagram of a typical PPPOA system application network.

FIG. 2 is a time curve diagram of the CPU usage rate of the PPPOA server when a fixed-length timer is used to trigger the renegotiation mechanism in the prior art.

FIG. 3 is a time curve diagram of the CPU usage rate of the PPPOA server when a timer of random length is used to trigger the renegotiation mechanism in the present invention.

Fig. 4 is a flow chart of timer length setting in the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the following examples are given and the present invention is further described in detail with reference to the accompanying drawings.

Because the difference of the PPPOA system information processing process is mainly on the trigger mode of the timer, and the difference of the trigger mode is the timer of which length to take, so the key of the present invention is to set the trigger timer length as a random timing length.

The value formula of the random timer is as follows:

Timer length = base time * (constant + random number) (1)

Among them, the base time is a self-defined constant, which is flexibly set by the application software; the constant is equivalent to the initial value, which is also a custom value; the random number is generated by calling the underlying time function of the PPPOA system in the prior art , according to formula (1), the length of the final generated timer is a random value related to time.

The length range of the timer is determined according to the amount of information sent and received by the PPPOA system. In general, the time length of the amount of information sent and received by the PPPOA system is in the range of 10-140 seconds. The base time is set by the application program, which is the unit length value of the time chip, such as setting to 0.1 second, 1 second, etc.; the constant is usually set to the minimum value estimated by the amount of information, such as setting to 100, etc. Since the base time and constant can be set, when the amount of information sent and received by the PPPOA terminal is large, the order of unit length of the base time and the constant can be set larger respectively; when the amount of information sent and received by the PPPOA terminal is small, the order of magnitude and constant of the base time can be set Set smaller respectively. The random number is generated by directly calling the underlying time function of the PPPOA system. The random function is different every time it is called. Due to the difference in the random value, it can be guaranteed that the timer length is still a random value when the base time is set to be the same as the constant.

The PPPOA system networking situation shown in Figure 1 is still taken as an example below. When the PPPOA terminal transmits information between the access device and the ESR through the RTU and ADSL server, that is, when the user terminal uses batch processing to send or receive information, as shown in Figure 4 For the flow chart that the timer length of the present invention is set, then, the present invention utilizes the random length timer to realize the method for triggering the renegotiation mechanism, as shown in Figure 4, comprises the following steps:

Step 400: ESR, that is, the PPPOA server creates a timer with a random length;

Step 401: Set the base time and constant required for calculating the length of the timer according to the unit length of the current time chip and the minimum estimated value of the current amount of information sent and received respectively. At the same time, the PPPOA system calls the underlying time function to set the random time required for calculating the length of the timer number;

Step 402: After the base time, constant and random number are set, calculate the timer time length according to formula (1): timer length=base time*(constant+random number);

Step 403: The CPU of the PPPOA server implements synchronous reception or transmission of information with the PPPOA terminal according to the obtained timer period.

It can be seen from the above embodiments that the timer length generated by formula (1) is used as the time of the random timer, and the trigger time of the timer can be amortized in a period of time, rather than at a certain moment at the same time trigger. Therefore, the PPPOA system resources of the server CPU can be better utilized. On the one hand, when the amount of transmitted information is large, a timer with a long time length can be created so that the PPPOA system will not cause resource unavailability; on the other hand, when the transmitted information When the amount is small, a timer with a short duration can be created so that the PPPOA system has no idle period, and the PPPOA system resources are fully used. Fig. 3 is a time curve diagram of the CPU usage rate of the PPPOA server when a timer with a random length is used to trigger the renegotiation mechanism. As shown in Figure 3, if 2000 PVCs are configured on the ESR, compared with using a fixed-length timer with a timing length of three seconds, that is, compared with Figure 2, using a random-length timer for timing, the CPU of the SPU board occupies The maximum value of the rate in a certain period of time dropped from the original 100% to 13%, and the CPU occupancy rate dropped significantly, which solved the situation that the PPPOA system resources were not available.

The preferred embodiments are given above, and the purpose, technical solutions and advantages of the present invention are further described in detail. It should be understood that the above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Within the spirit and principles of the present invention, any modifications, equivalent replacements, improvements, etc., shall be included within the protection scope of the present invention.

Claims (4)

1. A method for triggering a renegotiation mechanism based on the Asynchronous Transfer Mode (ATM) Point-to-Point Communication Protocol (PPPOA). When the PPPOA terminal sends and receives information through the access device and the PPPOA server, the PPPOA server first creates a timer, and then the PPPOA server The CPU at the end realizes synchronous sending and receiving information with the PPPOA terminal according to the time period of the created timer; it is characterized in that the PPPOA server creates a timer and further includes: a. Set the base time value and constant value for calculating the timer length respectively; b. Call the underlying time function of the PPPOA system to generate a random value for calculating the length of the timer; c. The result obtained by multiplying the constant value set in step a and the random value obtained in step b, and the base time value set in step a is used as the timer length to create a timer. 2. The PPPOA access method according to claim 1, characterized in that: the length of the timer is a random value ranging from 10 seconds to 140 seconds. 3. The PPPOA access method according to claim 1, characterized in that: the base time is set as the unit time value of the currently used time chip. 4. The PPPOA access method according to claim 1, characterized in that: said constant is set as the minimum estimated value of the currently transmitted information volume.

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