JPS61194960A - Detour regulating system - Google Patents

Abstract

PURPOSE:To attain the evenness of connecting quality in congestion between terminal stations by providing one or a plural of setting devices of the degree of detour regula tion in a telephone network, and a detour regulating control device at every output path of exchanges that constitute the telephone network. CONSTITUTION:At the bypass regulating control devices 91 and 92 of an exchange A, a ratio corresponding to the design load of the selected requesting traffic intensity of each line 31 and line 32 is calculated and is outputted to signal lines 134 and 135 and the loss probability (b) 31 of a slave line 31 is calculated and outputted to a signal line 164. The output of an exchange B is the same as that of the exchange A. So that the output path from an exchange T is only one, the ratio of the traffic intensity of a line 35 is calculated in one detour regulating control device 95 is outputted to a signal line 138. In a detour regulating degree setting device 96, the degreeof a congestion is calculated from the inputted ratio of the traffic intensity through signal lines 134-138 and the regulating degree of a slave circuit in which calls overflow in a congesting line is calculated. The regulating degree is transimtted to the exchange that executes a detour control, for example, each of the detour regulat ing control devices 91 and 93 of the exchange A and B, through signal lines 194 and 196 respectively.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a detour control method for a telephone network, and in particular to a detour control method during high load. When the number of calls from the subordinate line increases, some or all of the overflow calls from the subordinate line are kept busy without being diverted to the main line, and the overflow of calls to the main line is restricted to suppress the sudden increase in calls on the main line. The figure is an explanatory diagram of an example of a telephone network, and shows a telephone network in which switching diagrams A, B, C, and T are connected by lines 31 to 35. Exchange A,
B and C are terminal stations.

Switching station T represents a tandem station. It is assumed that lines 31 to 35 carry Fl in the direction of the arrow. Lines 31 and 33 are subordinate lines that allow detours to lines 32 and 34, respectively.
, 34, and 35 are independent lines that do not allow detours. A call from exchange A to exchange C is assumed to have a traffic volume, and a tpy'e call from exchange B to exchange C is assumed to be B.

In the conventional detour control method, when the call volume on a certain line becomes too high, in order to prevent overflowing calls from spreading to the entire network, calls are not sent to the line where the congestion has been detected. Restriction is performed at a uniform rate for all slave circuits to be overflowed, and no restriction is performed for calls that do not have slave circuits. - For example, if the line 35 is congested and the exchange A is notified of the congestion on the line 35, the call volume is when the line 31 is busy.

Detours to line 32 will be regulated in proportion to the current system, and talkie
connection or busy tone connection. For call B, detour restriction is performed at the same rate of K. If detour call restriction is performed at the same rate for the 0 subordinate line, the inter-end station call loss rate, which indicates the connection quality between subscribers, will generally be determined by the link call loss rate of the slave line. Inequality occurs. That is, there is a drawback that the inter-terminal call loss probability of a terminal station pair whose subordinate line has a low link call loss probability is low, and the inter-terminal call loss probability of a terminal station pair whose subordinate line has a high link call loss probability becomes high. In addition, detour call restrictions are not applied to calls that do not have a dependent line, and when the network is congested, there is an inequality in the call loss rate between terminals between calls that have a dependent line and calls that do not have an FC.

(Purpose of the invention) The present invention aims to equalize the connection quality between terminal stations when the network is congested by defining the current system for each subordinate line in the detour restriction system. According to the present invention, in a detour system in a telephone network, a plurality or one detour restriction degree setting device is provided in the telephone network, and a detour restriction control device is provided for each outgoing route of an exchange that constitutes the telephone network. The detour restriction control device determines the call loss rate for each outgoing route and the ratio of the added call volume to the design load and transmits it to the detour restriction degree setting device, and the detour restriction degree setting device determines the call loss rate and the ratio of the added call volume to the design load in advance. The degree of congestion is determined by comparing all of them with a predetermined congestion degree judgment threshold, and when congestion is determined, overflowing calls are added to the route where congestion is detected from the call loss rate of all the preceding subordinate circuits and the congestion degree. The method is characterized in that the detour current system of the dependent line is determined and notified to the detour control device of the dependent line, and the notified detour restriction control device does not permit detouring for some of the overflow calls based on the detour current system. A detour regulation method is obtained.

(Example) Next, embodiments of the present invention will be described with reference to the drawings.

FIGS. 1 and 2 are system configuration diagrams showing an embodiment of the present invention, each of which includes a detour restriction control device provided for each outgoing route of an exchange and a detour restriction level setting device provided in plural or one in the network. The detour restriction control device shown in FIG. A 0-call counting circuit 1 composed of a computing unit 49, a line selection circuit 39, a line selection circuit 6, and a distributor 5 selects calls that are requested to be selected to the outgoing route within υ unit time based on a selection request signal from a signal line 11. The number C is counted and the value is output to the signal line 12. In response to the selection request signal from the signal line 11, the line selection circuit 3 performs an operation to capture the outgoing line if it is present, and also measures the number of captures Cxf within a unit time and outputs it to the signal edge 15. (b) On the other hand, when the line is busy, the selection request signal is passed through as is and output to the signal line 14. The arithmetic unit 4 calculates the call loss rate bi=(CCx)/C of the dependent line from the number of selection request calls C from the signal line 12 and the number of captures Cx from the signal line 15, and outputs it to the signal @16. do. However, hereinafter, i is a subscript representing the dependent line.The operator 2 calculates the call volume ratio C/CO between the selected requested call number C from the signal line 12 and the preset design load call number CO, The 1 distributor 5 outputs to the signal line 13 the detour current system Ki received from the detour restriction degree setting device via the signal line 19.
Based on the selection request signal from the signal line 14 (
The 0 line selection circuit 6 distributes and passes the signal to the signal edge 17 at a rate of l-Ki and to the signal line 18 at a rate of Ki.
A line selection circuit or a busy tone selection circuit performs a talkie connection or a busy tone connection if the line is vacant in response to a selection request signal from the signal line 18. When the distributor 5 receives Ki=O, the selection request signal from the signal line 14 is passed through without any detour restriction and is output to the signal line 17.

In the exit routes other than the final stage of the detour, each circuit functions as described above, and signals are sent and received via each signal & I, but in the detour restriction control device installed on the exit route of the final stage of the detour, , the line selection circuit 6 is a busy tone selection circuit, and the signal edge 1
6 is not connected to the detour restriction degree setting device. Also signal line 19
From then on, Ki is always set to 1, and the selection request signal from the signal line 14 in the distributor 5 is directly connected to the busy tone. The detour restriction degree setting device shown in FIG. 2 includes the memory circuits 7L, 72.
. . , 73 and a 0 storage circuit 71, 72 . . . . . , 73 is a signal line 161 from the detour restriction control device of each exchange.

162, . . . , 163, the call loss rates bl, b2 . . . , bn (where WIN is the number of dependent lines controlled by the detour restriction control device) are stored. The numerical value setting circuit 8 is connected to signal lines 131, 132 . . . 1133, the ratio of the selected request traffic volume to the design load of each outgoing route is input, and is compared with a preset congestion degree determination threshold to determine the congestion degree of each. If congestion is detected.

The memory circuits 71, 72, .
. . , 73, calculates the value of parameter k (hereinafter referred to as regulation degree coefficient) for determining the current detour system Ki of the related dependent line from the content and the congestion degree, and further calculates the value of the parameter k (hereinafter referred to as regulation degree coefficient) Kama's detour current system Ki? Search signal line 191.192. ....

193, but is there a call to the route where the congestion is detected? :Ki=0 is transmitted to subordinate lines other than those to be overflowed.

The detour restriction system in the two-tier, one-stage detour network shown in FIG. 4 will be explained. Figure 3 shows the connection relationship between the detour restriction control device and the detour restriction level setting device installed in each exchange. Station B has detour restriction system equipment f193 and 94 corresponding to lines 33 and 34, respectively, and switching station T
A detour restriction control device 95 is provided corresponding to the line 35. The selection request signal outputted from the signal line 17 of the detour restriction control device 91 at the exchange A is sent to the detour restriction control device 9.
It is input via the signal line 1i of No. 2.

The same applies to exchange B. Detour regulation control of exchange group members! [In t91.92, each line 31. Determine the ratio of the selected requested call volume of the line 32 to the design load for each signal line 134.
．． 135, and the call loss probability b31 of the dependent line 31 is calculated and output to the signal line 164. The detour restriction control devices 93 and 94 of the exchange B calculate the call volume ratios of the respective lines 33 and 34 and output them to the respective signal lines 136 and 137, and calculate the call loss rate b33i of the dependent line 33 and output it to the signal line 166. Since there is only one outgoing route from the exchange T, one detour restriction control device 95 calculates the call volume ratio of the line 35 and uses the signal line 13.
Output to 8. The detour restriction degree setting device 96 calculates the congestion degree tX from the call volume ratio inputted through the signal lines 134 to 138, and when congestion is detected, determines the restriction degree of the dependent line that overflows calls to the congested line. A switching center that performs detour control for the subordinate circuit.

For example, the detour restriction control device 91 of each of exchanges A and B
゜93, the degree of regulation is sent via signals -194, 196 O. In normal times when no regulation is applied, that is, when Ki = 0, at exchanges A and El, The line selection circuit 3 performs an operation to capture the dependent line 31 or 33 if it is vacant, and passes the selection request code to the signal edge 14 when the dependent port is busy. Ki = from the signal line 19 to the distributor 5
0 is input, the selection request signal from the front distribution signal line 14 is transmitted to the signal line 17 without receiving the detour restriction side #, and the detour restriction of the independent line 32 or 34 of the detour light of the dependent port 4131゜33 is performed. Signal line 11 in control device 92.94
A selection request signal is input to , and a retrospective selection operation is performed.

Therefore, according to the usual detour method, line 31.
For call B, selection control for lines 33 and 34 is performed. On the other hand, the operation of detour regulation when one line 35 is congested will be explained below.

In the numerical setting circuit 8 of the detour restriction degree setting device 96, it is assumed that congestion has been detected at times @35 as a result of comparing the call volume ratio with a preset congestion degree determination threshold. Congestion degree af: is determined from the traffic volume ratio and the preset congestion degree determination threshold value. Also, at exchanges A and B, dependent lines 31.33
Based on the number of calls requested for selection and the number of captured calls in the line selection circuit 3, the call loss rate b31 of the dependent line is determined. b33 is determined and sent to the memory circuits 71 and 72 via signal lines 164 and 166. In the detour restriction degree setting device, the call loss rate b of the dependent lines 31 and 33 that overflows calls to the line 35 where congestion has been detected
31. The value of b33 is read from the memory circuits 71 and 72, and the regulation degree coefficient k is determined from that value and the congestion degree 1. As an example of how to give the regulation degree coefficient, when the measured number of calls is 1.5 times or more and less than 2 times the design load, congestion transformation = 0.5, and = 0.5% min (b31. b
33), and when it is twice or more, the congestion degree a = 0.
8, = 0.8Xmin (b31. b33)
However, here m1n(xi, x2...
) means XI, X2. From the restriction degree coefficient obtained in this way and the call loss rate b31, which is the minimum directness of ..., dependent times @3
Calculate 31 in the detour current system of 1 and send its contents to the signal @19
Output to 4. Similarly, the signal 33 is outputted to the signal line 196 in order to detour the related subordinate line 33. An example of how to give Ki in the current system is K i = k / b i, and 31 = /b31. Give 33=to/b33. Switching station A sends a call tS to the line where congestion has been detected;
The distributor 5 of the detour restriction control device 91.93 of the line 31.33 of B has 3 in the positive detour current system of the dependent line 31.33.
1. K33 is input via signal lines 194.196. In the switching waste detour restriction control device 91, an overflow call selection request signal from the subordinate line 31 is sent to the distributor 5 to select the overflow call selection circuit 6'f via the signal line 18 at a rate of 31 to the restriction level. The same goes for the 0 exchange B, which outputs the signal $17 at a ratio of (1 to 31) and inputs it via the signal line 11 of the detour restriction control device 92. Based on the value of the call volume ratio transmitted via the line 13 and the value of the call loss rate transmitted via the signal line 16, the current system K i f is determined and a part of the overflow calls from the dependent line is divided into the ratio of the current system Ki. to randomly restrict detours, connect to a talkie line, or connect to a busy tone, (IK
+) overflow calls are diverted to the next-step strategy.

When the measured value of the call volume ratio of congestion times or selection request calls becomes smaller than the set value, Ki=O is connected to the signal line 19.
If you send it via , the restriction will be automatically lifted.

In order to control the congestion of the exchange rather than the congestion of the line, the call count measurement circuit 1 and the performer 2 shown in Fig. 1 are installed on the incoming line side of the exchange and the selection request signal to the exchange is measured. It is also possible if congestion is detected. 1
In the case of a call in which two or more detour selection routes exist for one selection request, an arbitrary number of detour selection routes can be obtained by connecting the configurations shown in Figure 1 in cascade as shown in Figure 5. A detour restriction control system for exchange nodes can be configured.

However, in the detour restriction control device corresponding to the exit route of the final stage of detour, the line selection circuit 6 is a busy tone selection circuit, the signal line 16 is not connected to the detour restriction degree setting device, and the signal line 19 is connected to the detour restriction degree setting device. It is assumed that K i =1 is always input. Further, when there is no dependent line, the line to be selected by the line selection circuit 3 is always all busy, and the arithmetic unit 4 always outputs a call loss rate=1.

The same effect as that of the present invention can be obtained by performing part of the function of the numerical value setting circuit 8 in the embodiments of FIGS. 1 and 2 by the arithmetic unit 2.
You can also get it. For example, arithmetic unit 2
calculates the congestion degree a and outputs it to the signal line 13,
The current system is calculated from the received congestion degree a in the numerical value setting circuit 8.

(Effects of the Invention) FIG. 6 shows the performance evaluation results of the system of the present invention in the telephone network shown in FIG. 4.

Lines 321, 34, and 35 have a normal load as a background call volume, and when calls A and B'i are increased at a constant rate with respect to the design load, the congestion degree a is taken as a parameter, and the horizontal axis is The multiplication factor for the designed load of the line 35 is shown, and the vertical axis shows call 1 (erl) overflowing from the network.

A comparison will be made between the conventional method of applying regulations at a uniform rate with congestion degrees at 0.5 and 0.8, the regulation method according to the present invention, and the method of not adding regulations. Here, the regulation degree coefficient ki is the dependent line 3 that overflows calls to the crowded line 35.
Call loss rate of 1°33 b31. From the value of b33, k =
a K33
An example is shown in which the call loss rates b31 and b33 of the subordinate lines are given as 31"k/b31. When the load is more than .5 times, traffic overflow from the network will be reduced if the congestion degree is regulated at a = 0.5.Furthermore, when the design load is more than twice the design load, if a-0°8 is set, then a = 0. Compared to the case of .5, overflow from the network is further reduced, and this is true for the principle of network control during high load, which is to maximize call communication. The overflow from the original network is reduced compared to the conventional detour control system using uniform control vehicles. Therefore, in the area of 1.5 times or more and less than 2 times the design load, a = 0.5, the design load Comparison of a method in which detour restriction is uniformly implemented using a-0, 8 in an area more than twice the area of , regardless of the call loss rate of the dependent line, and a method in which restriction is implemented using a restriction vehicle that is inversely proportional to the link call loss rate for each dependent line. The 0 horizontal axis in Figure 7 shows the call volume applied to the line 35 by taking the ratio of the loss rate between the end offices between exchange A and 0 and the loss rate between the end stations between exchange B and 0. For example, when the multiplication factor is 1.5 and the congestion degree a = 0.5, when the regulation is strictly enforced, between exchange A, 0 and exchange B, 0. The ratio of the external loss rate between terminal stations is about 1.8, and the connection quality is unequal, but if the restricted car is set in inverse proportion to the call loss rate of the dependent circuit, exchange A, 0. Almost the same inter-office call loss rate can be obtained between exchanges B and 0, and the connection quality between each station can be equalized.

As explained above, 1. When an overload exceeding the design load occurs, the present invention provides a regulation that controls detours from each subordinate line by a restricted vehicle determined based on the call loss rate of the subordinate line when performing detour regulation. As explained in Figures 6 and 7, the amount of calls carried by the network will be greater than the amount of calls carried by the conventional detour control method, and furthermore, as explained in Figures 6 and 7, This has the advantage of being able to average out the loss rate. Further, even when there is no line in the dependent line, the same effect can be obtained by setting the call loss rate of the dependent line to 1 and performing detour control in the same way.

In addition, if the function of the detour restriction level setting device is made compatible with each exchange, the numerical value setting method in the numerical value setting circuit 8 may be changed;
For example, it is difficult to change the congestion level judgment threshold for calculating the congestion level or to use their average value or constant instead of the minimum value of the related dependent lines when calculating the regulation level coefficient. Furthermore, the cost of the detour restriction control device for each station is high, and the call loss rate, call volume ratio, and number of signal lines for transmitting and receiving restricted vehicles are large. Yes, these points are also resolved.

[Brief explanation of the drawing]

FIG. 1 is a system configuration diagram of an embodiment of the detour restriction control device of the present invention, FIG. 2 is a system configuration diagram of an embodiment of the detour restriction level setting device, and FIG. 3 is a system configuration diagram of an embodiment of the detour restriction level setting device and the detour restriction control device. FIG. 4 is an explanatory diagram of an example of a telephone network,
Fig. 5 is a system configuration diagram of the present invention when two or more detour selection routes exist, Fig. 6 is an explanatory diagram of the call volume overflowing from the network with respect to the increase rate of call volume at the time of overload, and Fig. 7 FIG. 2 is an explanatory diagram of the ratio of the loss rate between terminals of the two exchanges -C and B-C to the increase rate of call volume. In the figure, 1...Call count measuring circuit, 2, 4...Arithmetic unit, 3, 6...
...Line selection circuit, 5...Distributor, 71-73...
Memory circuit, death... Numerical setting - path, 91-95... Detour restriction control! 1! , 96...Detour restriction level setting device, A
, B, C. T... Switching station. Agent zr31! Written by Susumu Shiuchi Hara

Claims (2)

[Claims] (1) In the detour system in the telephone network, a plurality or one detour restriction degree setting device and a detour restriction control device are provided for each outgoing route of the exchange that constitutes the telephone network, and the detour restriction is implemented. The control device calculates the call loss rate for each outgoing route and the ratio of the added call volume to the design load and sends it to the detour restriction degree setting device, and the detour restriction degree setting device determines the call volume ratio and the predetermined congestion degree. The degree of congestion is calculated by comparing the congestion with a threshold value, and when congestion is determined, overflow calls are added to the route where congestion is detected.Detour control of the dependent line is determined based on the call loss rate of all preceding subordinate lines and the congestion degree. 1. A detour restriction method, characterized in that the detour restriction control device determines the detour restriction degree and notifies the detour control device of the dependent line, and the notified detour restriction control device does not permit detouring for some of the overflow calls based on the detour restriction degree. (2) The detour restriction method according to claim 1, wherein the detour restriction degree is a value obtained by dividing the restriction degree coefficient by the call loss rate of the dependent line.