JP2809142B2 - Overflow call bypass method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiplexing apparatus having a demand assigning function for setting a communication line each time a call is generated and a function of bypassing an overflowing call to a public line when a call overflows. It relates to the overflow call rerouting method.

[0002]

2. Description of the Related Art In a multiplexing apparatus of this kind, when a new call is generated, the usage rate of a dedicated line is checked in order to set up a new line. When the usage rate of the leased line exceeds a predetermined threshold value, it is connected to a public line to bypass an overflow call through the public line.

FIG. 6 is an explanatory diagram for explaining the operation of such a multiplexer. In the multiplexing apparatus 2, 64 kbps, 48 kbps, 32
It accommodates five channels (lines) 11 to 15 having communication speeds of kbps, 16 kbps, and 8 kbp.
Here, it is assumed that these five channels are "channels in which connection delay to the public line 4 cannot be tolerated". Also,
A dedicated line 3 having a communication speed of 128 kbps is prepared as a connection destination. It is assumed that the threshold value described above is set so that no call overflows to the dedicated line 3 which is an output line even if allocation requests are made simultaneously from up to two channels.

Here, in order to guarantee simultaneous allocation of up to two channels among the accommodated channels, a high-speed 64k
The threshold value of the dedicated line 3 is determined by the following equation in consideration of two channels of bps and 48 kbps. That is, threshold value = {128 kbps (dedicated line) −64 kbps−48 kbps} / 128 kbps (dedicated line) = 12.5%.

If the threshold value of the dedicated line 3 exceeds 12.5% when a call is generated on a new channel, the delay of connection of the new call to the public line 4 is allowed. Therefore, the multiplexer 2 connects the public line interface 24 to the public line 4.

[0006]

As described above, in the conventional multiplexing apparatus, when a high-speed channel is provided, the dedicated line 3 is considered in consideration of the connection delay of the overflow call to the public line 4.
The threshold value is set low. For this reason, when a new call occurs, a situation often occurs in which the threshold value of the dedicated line 3 is exceeded, and a bypass connection to a public line having a high usage fee is performed in advance, and
Since the transfer of the overflow call via such a bypass is not always performed every time the bypass is formed, there is a problem that the operation cost of the line increases, and the efficiency of the operation cost of the line decreases. . Therefore, an object of the present invention is to connect and disconnect a public line at an appropriate timing to reduce the line operation cost and improve the line operation cost efficiency.

[0007]

SUMMARY OF THE INVENTION In order to solve such a problem, the present invention has a demand assigning function of allocating a channel on which a call has been made to a dedicated line when a call is made on the accommodated channel, and has a demand assigning function for allocating the channel to the dedicated line. In a multiplexing device having an overflow call rerouting function for rerouting an overflowing call to a public line, the attribute of a plurality of accommodated channels is set to a first attribute that does not allow a connection delay of the public line, and a connection delay of the public line is allowed. and classifying means for classifying the third attribute is not necessary even to bypass a second attribute and overflow possible, the communication speed of the channel of the first attribute of the unconnected channels before the call overflows the dedicated line Priority determining means for determining the connection priority of the channel from the past usage rate, and extracting the unconnected channels by the preset number of channels in accordance with the connection priority order. And determining means provided for unconnected channels that are extracted to determine whether assignable to a dedicated line, in the case of assignment impossible is obtained so as to ensure in advance detour by connecting a public line. As a result, since the connection to the public line is made at an appropriate timing, the operation cost of the line can be reduced, and the efficiency in the operation cost of the line can be improved. Further, a detection means for detecting the presence or absence of a channel bypassing the public line is provided. When the detection means detects that the public line has no detour channel, the connection priority order is determined by the preset number of channels. And disconnects the public line if the extracted non-connected channel can be assigned to a dedicated line. As a result, the operation cost of the line can be similarly reduced.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 4 is a block diagram showing a configuration of a multiplexing apparatus to which the overflow call rerouting method according to the present invention is applied. In the figure, 11 to 1N are channels (lines), 2 is a multiplexer, 3 is a dedicated line, and 4 is a public line. Here, the multiplexing device 2 includes channel interfaces 211 to 21N which are interfaces of the channels 11 to 1N, a time division multiplex switch 22, a dedicated line interface 23 which is an interface with the dedicated line 3, and an interface with the public line 4. It comprises a public line interface 24, a central control unit 25, and a storage device 26.

The central control unit 25 has, for example, a channel 11
When the occurrence of a call is detected via the channel interface 211, the time division multiplex switch 22 is controlled so that the path between the channel 11 and the dedicated line 3 is connected. As a result, the terminal connected to channel 11
Data communication and the like via the channel 11 and the dedicated line 3 are performed at the communication speed inherent to the channel 11. Next, when the path between the channel 11 and the leased line 3 is formed, for example, when a call is made to the channel 12, the central controller 25 causes the path between the channel 12 and the leased line 3 to be connected. Controls the time division multiplex switch 22. As a result, on the dedicated line 3, data communication is performed at the communication speed obtained by summing the communication speeds of the channels 11 and 12.

Thus, when each of the channels 11 and 12 is connected to the dedicated line 3 and data communication or the like is performed via the dedicated line 3 at the total speed of each channel, for example, the channel 1
When a call is made to N and the speed capacity of the dedicated line 3 is insufficient at this time, the central controller 25 controls the time division multiplex switch 22 so that the path between the channel 1N and the public line 4 is connected. . And the public line interface 24
, And the call of the channel 1N overflowing from the dedicated line 3 is bypassed via the public line 4.

By the way, in the conventional multiplexing apparatus, a threshold value relating to the speed capacity of the dedicated line 3 is set in advance so that a call overflowing from the dedicated line 3 can be bypassed to the public line 4 without delay. However, when a high-speed channel is accommodated, the threshold value of the dedicated line 3 is set to a low value.
The threshold value is often exceeded, and a connection is made to a public line having a high usage fee, which causes a problem that the efficiency is reduced due to the operation cost of the line.

For this reason, the multiplexer 2 first determines the connection priority of each of the accommodated channels 11 to 1N. That is,
The connection priority of a channel from a certain time to after t0 of the time can be represented by the product of the speed of the channel and the usage rate of the channel, and therefore, the priority Y (i) of the channel i is , Y (i) = v (i) .t (i) / t0 (1) Where v (i) is the speed of channel i, t
(I) represents the use time of the channel i, t0 represents the operation time of the multiplexer 2, and t (i) / t0 corresponds to the channel utilization rate.

FIG. 1 is a flowchart showing the operation of the central control unit 25 showing such a channel priority determination operation. That is, in step S11, the use time of the channel i from the time t0 before to the present is acquired. Subsequently, in step S12, the quotient of the use time of the channel i and the time t0 is taken as the channel use rate, and in the following step S13, the priority of the channel i is determined from the calculated channel use rate and channel speed.

Next, the attributes of the channels accommodated in the multiplexer are classified into the following three attributes. That is, the first
As attributes of “channels that cannot tolerate connection delay of public line”, as a second attribute, “channels that can tolerate connection delay of public line”, and as a third attribute, “channels that do not need to be bypassed even if overflowed”, Classify each.

[0015] Of these channels, among the "channels in which connection delay of the public line 4 cannot be tolerated" having the first attribute, n channels (n: It is determined whether or not the channel (pre-registered value) can be allocated in the dedicated line 3 and
If allocation is not possible, connect a public line and secure a detour. That is, as shown in the flowchart of FIG. 2A, the central controller 25 monitors n channels extracted in order of priority among the unconnected channels (step S2).
1) It is determined whether or not the next extracted n channels can be assigned to the dedicated line 3 (step S22). If the assignment is not possible, the public line 4 is connected (step S23).

When the public line 4 is disconnected, the central control unit 25 in the multiplexer 2 operates as follows. That is, as shown in the flowchart of FIG. 2B, when the presence or absence of a channel bypassing the public line 4 is detected and there is no bypass channel (step S24), the channel priority of the unconnected channels is higher. M extracted in order
Monitoring is performed for this (m is a previously registered value) channel (step S25). Then, it is determined whether or not the m channels can be allocated in the dedicated line 3 (step S).
26) If the assignment is possible, the public line 4 is disconnected (step S27). The threshold value of the dedicated line 3 can be adjusted by changing n and m.

Next, in the "channel that can allow connection delay of the public line" having the second attribute, as shown in the flowchart of FIG. 3, when a channel allocation request from a storage medium (not shown) is generated (step S31). ),
The central controller 25 determines whether or not the call overflows (step S32). If the call overflows, the central controller 25 connects the public line 4 to secure a detour (step S33). In addition, public line 4
Is the same as the operation in the case of "the channel in which the connection delay of the public line cannot be tolerated" shown in FIG.
In a “channel that does not need to be detoured” having the third attribute, the central control device 25 operates so as not to make a detour even when a call overflows.

Here, a specific use example of connection of the “channel that cannot allow connection delay of the public line” having the first attribute to the public line 4 will be described with reference to FIG.
First, as shown in FIG. 5A, the multiplexing apparatus 2 sets v (1)
= 64 kbps, v (2) = 56 kbps, v (3) =
48 kbps, v (4) = 32 kbps, and v (5)
It is assumed that five “channels in which connection delay of a public line cannot be tolerated” having respective speeds of = 16 kbps are accommodated via each channel interface 21.
Then, it is assumed that a 128 kbps dedicated line is prepared as a connection destination, and "2" is registered in advance as the number n of channels extracted in the order of priority.

Now, a channel 11 of 64 kbps is connected to the dedicated line 3 and the remaining four channels 12, 13,.
14 and 15 are not connected. At this time, the usage rates of the four unconnected channels 12 to 15 are t (2) / t0 = 1/8 and t (3) / t0 = 2 / 8, t
Assuming that (4) / t0 = 2/8 and t (5) / t0 = 3/8, the priorities Y (2) to Y (5) of the unconnected channels 12 to 15 are given by the equations (1). Y (2) = 7, Y (3) = 12, Y (4) = 8, Y
(5) = 6, and therefore the priority order of the unconnected channels 12 to 15 is Y (3)> Y (4)> Y (2)> Y (5).

Here, the remaining capacity of the dedicated line 3 is 64 kbps.
And the speeds 4 of the two channels I3 and I4 extracted in descending order of priority among the four unconnected channels 12 to 15.
Compared with the sum of 8 kbps and 32 kbps (80 kbps), since the remaining capacity of the dedicated line 3 is smaller, the central controller 25 controls the public line interface 24 to connect the public line 4 to the multiplexing device 2. , To secure a detour when an overflow call occurs.

Further, as shown in FIG.
The channel I5 of 16 kbps is connected within
When the two channels I1 to I4 are unconnected, the usage rates of the unconnected channels I1 to I4 are t (1) / t0 = 2/8 and t (2) / t0 = 1/8, respectively. , T
Assuming that (3) / t0 = 2/8 and t (4) / t0 = 2/8, the priorities Y (1) to Y (4) of the unconnected channels I1 to I4 are expressed by the following equation (1). Y (1) = 16, Y (2) = 7, Y (3) = 12, Y
Since (4) = 8, the priorities of the unconnected channels I1 to I4 are Y (1)> Y (3)> Y (4)> Y (2).

Here, the remaining capacity of the dedicated line 3 is 112 kbp.
When s (128 kbps-16 kbps) is compared with the sum (112 kbps) of the respective 64 kbps and 48 kbps of the two channels I1 and I3 extracted in descending order of priority among the four unconnected channels, they are equal. In this case, connection to the public line 4 is not performed.

As described above, each trigger for connection to the public line 4 and disconnection of the public line 4 is finely controlled according to the attribute, speed, and usage rate of the unconnected channel. And the public line 4 can be used.

[0024]

As described above, according to the present invention, the attributes of a plurality of channels accommodated therein are defined as a first attribute which cannot tolerate a connection delay of a public line and a second attribute which can tolerate a connection delay of a public line. And the third that does not need to be detoured even if it overflows
Classified into attributes, communication speed for the channel of the first attribute of the unconnected channels before the call overflows the dedicated line
When one of determining the connection priority of the channel from the past utilization, number of channels set in advance, to extract the unconnected channels in accordance with the above connection priority order, the extracted unconnected channels or be assigned a dedicated line Judgment as to whether or not it is possible to connect to the public line if it is not possible to allocate, so that it is possible to connect to the public line at an appropriate timing, thus reducing the line operation cost and reducing the line operation cost. Efficiency can be improved. In addition, the presence or absence of a detour channel in the public line is detected, and when it is detected that the detour channel is lost in the public line, unconnected channels are extracted in accordance with the order of connection priorities for the preset number of channels, When the extracted unconnected channel can be assigned to the dedicated line, the public line is disconnected, so that the line operation cost can be similarly reduced.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a priority determining operation of each channel in a multiplexing apparatus to which an overflow call rerouting method according to the present invention is applied.

FIG. 2 is a flowchart showing an operation of connecting and disconnecting the multiplexing device to and from a public line.

FIG. 3 is a flowchart showing another example of the connection operation of the multiplexer to the public line.

FIG. 4 is a block diagram of a multiplexer.

FIG. 5 is an explanatory diagram specifically showing an operation of a main part of the multiplexer.

FIG. 6 is an explanatory diagram showing an operation of a conventional multiplexer.

[Explanation of symbols]

11-1N channel, 2 multiplexer, 3 dedicated line, 4 public line, 211-21N channel interface, 22 time division multiplex switch, 23 dedicated line interface, 24 public line interface, 25 line interface Central control unit.

Continuation of the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) H04L 12/28-12/66 H04M 3/00 H04M 7/00

Claims (2)

(57) [Claims] 1. A multiplex having a demand assigning function for allocating a channel in which a call has occurred to a dedicated line when a call is generated in an accommodated channel, and an overflow call bypassing function for bypassing an overflow call overflowing from the dedicated line to a public line. In the digitalization device, the attributes of the plurality of channels accommodated are classified into a first attribute that does not allow connection delay of the public line, a second attribute that allows connection delay of the public line, and a third attribute that does not need to be bypassed even if it overflows. and classifying means for classifying an attribute, the priority determining the call to determine the connection priority of the channel and a communication speed and past usage of the channel of the first attribute of the unconnected channels before overflowing from dedicated line Means for extracting unconnected channels by the preset number of channels in accordance with the connection priority order, and determining whether the extracted unconnected channels can be allocated to a dedicated line. And a determination means for, allocation impossible overflow call diversion schemes, characterized in that to secure in advance a bypass path connecting a public line in the case of. 2. The overflow call rerouting method according to claim 1, further comprising detecting means for detecting the presence or absence of a channel detouring to the public line, wherein the detecting means detects that the detour channel has disappeared on the public line. And an unconnected channel is extracted according to the connection priority order for a predetermined number of channels, and the public line is disconnected if the extracted unconnected channel can be allocated to a dedicated line. .