JPH05252182A - Polishing control system - Google Patents

Abstract

PURPOSE:To simplify a monitoring mechanism while satisfying communication quality guaranteed for a call when the call is set. CONSTITUTION:The clock of a clock generator 313 is counted by a counter 312, and also, the count value of the counter 312 at that time is supplied to a comparator 314 as a cell time (n) by the output of a cell transfer control part 311 generated at every arrival of the cell. In such a case, the cell time (n) is compared with a preset value n' (= allowable minimum cell interval 1/M') set on a register 315 in advance, and when it is decided that the cell time (n) is smaller than the prescribed value n', the cell transfer at the cell transfer control part 3 is permitted, and when the former is larger than the latter, the cell transfer at the cell transfer control part 3 is inhibited.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a policing control system used in an ATM switching network.

[0002]

2. Description of the Related Art Recently, as an exchange system for realizing multimedia communication such as voice, data communication and image processing, A
TM (Asynchronouse Transfer Mode) exchange is being put to practical use.

In such an ATM, a so-called cell in which routing information called a header is added to information divided into fixed lengths is used as a unit, and information is transferred by such a cell. Therefore, as compared with the STM (Synchronouse Transfer Mode) method, which allocates a fixed time slot on the transmission path to transfer information,
A flexible user interface can be realized.

By the way, in order to actually transfer information by ATM, a logical connection called VC (Virtual Channel) is set at the request of a terminal which communicates prior to the transfer of information, and the VC of the set VC is set. A cell including actual communication information is transferred along the route.

When setting such a VC, the VC is based on the characteristics of the cell flow generated by the communication (a parameter indicating this is called a declaration parameter).
The communication quality after the setting is predicted, and the VC is set only when the predetermined communication quality can be satisfied. By performing such call setting control, the ATM guarantees a predetermined communication quality for each communication.

In this case, the above-mentioned declared parameters logically define the characteristics of the VC cell flow, and cells can be physically generated continuously at the interface speed. For this reason, cells that exceed the characteristics (declaration parameters) of the cell flow used for call setting control may flow into the network, and in this case, the realized communication quality is worse than the predicted communication quality. As a result, communication quality cannot be guaranteed.

Therefore, in the prior art, each V is connected at a connection point to the switching network so that such an excessive inflow of cells does not occur.
The cell flow is monitored for each C, and policing control is performed to regulate the inflow of excessive cells.

By the way, it is desired that the call setting control algorithm be as simple as possible due to the connection delay time, the capacity of the call setting control device, the cost, and other restrictions. Therefore, in reality, call setup may be performed or bandwidth may be allocated without using all the information included in the report parameters, and even if the values of the report parameters differ, call setup control may be performed. It may be treated exactly the same. An example of this is a case where the declaration parameter is made up of a plurality of parameter sets and only a part of them is taken into consideration when call setting is performed.

However, conventionally, even when such a simple call setting algorithm is used, each V
Policing control for restricting the inflow of excessive cells is performed for the reporting parameters for each C.

[0010]

However, as described above, when the call setting control such as whether or not the call setting is possible and the band allocation is performed without using all the information included in the declaration parameter, the declaration parameter is not protected. Even if there is a cell flow, as long as the call setup control algorithm is met, even if a cell flows into the network, it does not affect the communication quality guaranteed by the network. Therefore, even in such a case, it is useless to monitor whether or not the declared parameters are faithfully observed for each VC by policing control, because the monitoring mechanism becomes unnecessarily complicated.

The present invention has been made in view of the above circumstances, and provides a policing control system capable of satisfying the communication quality guaranteed for a call at the time of call setting and realizing a simplified monitoring mechanism. The purpose is to do.

[0012]

A policing control system of the present invention is a first system which exhibits cell transmission characteristics between a terminal and a communication network.
After determining the parameter, determining whether or not to set the logical connection between the terminal and the communication network and allocating the band by using the first parameter, and after starting the communication,
AT for monitoring cell transmission for each set logical connection setting
Used in the M-switching network, the first parameter is obtained as a second parameter by a predetermined arithmetic processing,
For the first parameter that is a value that violates the determination of whether or not the logical connection can be set and the band allocation, a value that regulates the cell transmission characteristics is set as the second parameter, and the first parameter that does not violate is set. The parameter is set so that a value that does not need to regulate the cell transmission characteristic is set.

[0013]

As a result, according to the present invention, regarding the function of the parameter to be monitored, in determining whether or not the logical connection can be set and allocating the band, the first parameter that violates these is set to the second parameter as the cell. A value that restricts the transmission characteristics is given, and a value that does not impose restrictions on the cell transmission characteristics is given to the first parameter that does not violate, and the communication quality guaranteed for the call when setting the call. It is possible to maintain the above, and at the same time, it is possible to realize simplification of the monitoring mechanism.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic configuration of a network to which this embodiment is applied. In this case, the case where communication is performed between the terminal 1 and the terminal 2 is shown. When a communication request is generated by the terminal 1, VCs are set for the subscriber exchange 3, the relay exchange 4, and the subscriber exchange 5, respectively. , Cells including communication information are transferred along these VC paths.

In this case, for cells generated from the terminal 1, the policing control unit 31 provided in the subscriber exchange 3 monitors the characteristics of the cell flow, while for cells generated from the terminal 2, the subscriber exchange is used. The characteristics of the cell flow are monitored by a polishing controller 51 provided in the unit 5.

In this embodiment, the declaration parameter is V
C average rate V (cell / unit time) and maximum rate M
(Cell / unit time) set, but when the VC is set by the communication request from the terminal 1, the bandwidth is allocated at the maximum rate M ′ (cell / unit time) in order to reduce the processing amount at the time of setting. .. Then, when a call connection is requested, the call is accepted only when the value obtained by adding the maximum rate M ′ to the already allocated band is less than or equal to the capacity of all transmission lines. Here, the value of M ′ is set to be equal to or higher than the maximum rate M of the declared parameters, and is determined in consideration of the traffic deformation of the cell flow from the terminal 1 to the policing control unit 31.

Therefore, in the policing control by the policing controller 31, the maximum rate of the VC cell flow to be monitored is M '.
It is possible to maintain the communication quality guaranteed at the time of call setting by monitoring that the minimum allowable cell interval is not less than 1 / M '.

Next, a specific example will be described with reference to FIG.

FIG. 2 shows a schematic configuration of the policing controller 31. In the figure, 311 is a cell transfer control unit, and this cell transfer control unit 311 is the terminal 1 described in FIG.
The cell transfer that occurs more is controlled. Further, the cell transfer control unit 311 generates an output each time a cell arrives and gives this output to the counter 312.

The counter 312 has a clock generator 313.
The clock output is counted every cell time, and the count value is output to the comparator 314 as the cell time n each time the output from the cell transfer control unit 311 is given.

The comparator 314 has a preset value n '(= allowable minimum cell interval 1 / set by the register 315).
M ') is given, this set value n'and the counter 3
The comparison result with the cell time n given by 12 is output. In this case, if the cell time n is equal to or greater than the predetermined value n ′, the counter 312 is reset by the output of the comparator 314 at this time, and the cell transfer control unit 31
1 is permitted, while the cell time n is a predetermined value n
If it is smaller than ', the output of the comparator 314 at this time prohibits cell transfer in the cell transfer control unit 311.

Therefore, it is monitored that the cell time n of the cell transferred from the terminal 1 to the transfer control unit 311 does not become less than the set value n '(= allowable minimum cell interval 1 / M'). Since it is guaranteed that the cell flow actually flowing into the network is equal to or lower than the maximum rate M'allocated at the time of call setup, the communication quality can be surely guaranteed. Further, in this case, only the maximum rate of the VC among the characteristics of the cell flow which is the declared parameter is monitored, and the average rate is not monitored, so that the monitoring and control device can be simplified. This means that, for example, when a leaky bucket is used as a means for monitoring the average rate, a statistical declaration parameter is regulated by the monitoring although the average rate declared by the cell flow is observed. Of course, there are no inherent problems.

Next, another embodiment of the present invention will be described.

In this embodiment, the declared parameter is the maximum rate M (cell / unit time) at which the continuous value of VC is taken, whereas at the time of call setting, a constant value Max (cell / unit time) is an integral part. A discrete value (Max
Bands are allocated by a function M '= f [M] of M taking / n). When a call connection is requested, the call is accepted when the value obtained by adding the maximum rate M ′ to the already allocated band is less than or equal to the capacity of all transmission lines. Here, the value of M'is the maximum rate M of the reporting parameters.
That is all.

Therefore, in the policing control by the policing controller 31, the maximum rate of the cell flow of the VC to be monitored is M '.
By monitoring that the call quality is not exceeded, the communication quality guaranteed at the time of call setup can be maintained.

Next, a specific example will be described with reference to FIG.

FIG. 3 shows a schematic configuration of the policing control unit 31. Here, the same parts as those in FIG. 2 described above are designated by the same reference numerals. In this case, the cell transfer control unit 311
Generates an output each time a cell arrives from the terminal 11 and supplies this output to the counter 312. The counter 312 increments its value by 1 each time the output from the cell transfer control unit 311 is given, and every time the clock of the 1 / M ′ (n / Max) time period outputted from the clock generator 313 is given. I am trying to decrement by one. In this case, the counter 312 is not decremented any more when its count value is zero.

The count value of the counter 312 is sent to the comparator 314 every time it is incremented by 1 upon arrival of a cell. When the count value of the counter 312 is determined to be 1 or less, the cell transfer control unit 311 determines. Cell transfer is permitted, and when it is determined that the count value of the counter 312 exceeds 1, the cell transfer in the cell transfer control unit 311 is prohibited.

Therefore, the cell transferred from the terminal 1 to the transfer control unit 311 has a cell time of 1 / M '(n / Ma).
x) is monitored, and it is guaranteed that the cell flow actually flowing into the network is equal to or lower than the maximum rate M'allocated at the time of call setup, so that the communication quality is surely guaranteed. It becomes possible to do. Further, since the time period required for the clock output from the clock generator 313 is always an integral multiple of 1 / Max, even when monitoring a plurality of VCs, the clock of the 1 / Max time period is used. If there is one, it can be used by dividing it, and even further simplification of the hardware is realized compared to the case where the maximum rate M that takes a continuous value must be monitored. become able to.

The present invention is not limited to the above-mentioned embodiment, and can be carried out by appropriately modifying it without changing the gist.

[0032]

As described above, according to the present invention, when a call is set, the communication quality guaranteed for the call can be maintained and the monitoring mechanism can be simplified. It is possible to reduce the hardware scale and thereby reduce the cost.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of an embodiment of the present invention.

FIG. 2 is a diagram showing a schematic configuration of a polishing control unit used in the embodiment shown in FIG.

FIG. 3 is a diagram showing a schematic configuration of a polishing control unit used in another embodiment of the present invention.

[Explanation of symbols]

1, 2 ... Terminals, 3, 5 ... Subscriber switch, 31, 51 ... Policing control unit, 311 ... Cell transfer control unit, 312 ... Counter, 313 ... Clock generator, 314 ... Comparator, 3
15 ... Register, 4 ... Relay switch.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuaki Iwamura No. 1 Komukai Toshiba-cho, Sachi-ku, Kawasaki-shi, Kanagawa Stock company Toshiba Research Institute

Claims (1)

[Claims] 1. A first parameter indicating a cell transmission characteristic is determined between a terminal and a communication network, and whether or not to establish a logical connection between the terminal and the communication network is determined using the first parameter. In the ATM switching network that monitors the cell transmission for each set logical connection after allocating the bandwidth and the bandwidth and further starting the communication, the first parameter is used as the second parameter by the predetermined arithmetic processing. For the first parameter having a value that violates the determination as to whether or not to set the logical connection and the band allocation, a value that regulates the cell transmission characteristic is set to the second parameter, and A policing control method characterized in that a value that does not need to regulate cell transmission characteristics is set for the first parameter that does not violate.