JPS6228917B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a communication channel control system, and more specifically, to a communication channel allocation control system in a time division circuit switching system.

The line concentrator for terminals and the time-division exchanges and between the time-division exchanges are connected by a time-division multiplex communication path (highway), and bit signals in a frame structure are transmitted on this time-division multiplex communication path (highway). flows. When terminals with different communication speeds are accommodated, a low-speed communication channel is configured for low-speed communication by, for example, allocating one bit at a certain position in the frame, and similarly, a low-speed communication channel is configured for medium-speed communication. For example, for 5x speed, 5 bits at a fixed position in one frame are assigned, and for high-speed communication, for example, for 20x speed, 20 bits at a fixed position in 1 frame are assigned. Medium-speed and high-speed communication channels are configured. In this case, the bits assigned to one communication channel must have equal bit spacing. In this way, a plurality of communication channels having different speeds can be configured using time division multiplexed communication channels. A group of communication channels with equal speeds will now be called a channel band. Generally speaking, time-division multiplex communication channels are divided into several communication channel bands ranging from low-speed communication to high-speed communication.

Communication is established when a concentrator or switch selects and allocates one communication channel from a communication channel band suitable for communication speed.

In the time-division circuit switching system, for this type of communication channel, conventionally the number of communication channels belonging to each speed-based communication channel band was fixedly allocated in accordance with the communication traffic. Furthermore, it was possible for maintenance personnel to manually change the allocation of each communication channel band.

On the other hand, communication traffic for each communication speed changes from moment to moment. For this reason, fixed allocation of communication channel bands according to the conventional method cannot quickly respond to changes in traffic, leading to a decrease in the usage rate of communication channels. In addition, in order to prevent this, it is disadvantageous that it is wasteful to have a maintenance person wait for control to reset the communication channel band so as to immediately respond to the traffic condition.

The present invention eliminates the drawbacks of the conventional methods described above, monitors the usage rate of communication channel bands by speed, automatically changes the allocation of communication channel bands to match the communication traffic, and improves the usage rate of communication channels. The purpose is to facilitate the passage of traffic.

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing connections in an example in which the present invention is implemented for communication channel allocation control of a time division multiplex communication path (data path) connecting two time division line exchanges. In the figure, A and B are time-division line exchanges, respectively, and each exchange A and B is a time-division switch 1, a usage rate monitoring circuit 2, a control signal transmission/reception circuit 3, and a processing device 4 that controls these circuits.
(so-called central control unit). The exchanges A and B are interconnected by a data path S ₁ and a signal path S ₂ .

Data path S ₁ is a time division multiplex communication path (highway)
It is assumed that the communication channels are arranged as shown in FIG. 2, for example. That is, a high-speed communication channel band HCB having high-speed communication channels HC ₁ to HC _l , a medium-speed communication channel
Medium-speed communication channel band MCB with MC ₁ to MC _n
and a low-speed communication channel band LCB having low-speed communication channels LC ₁ to LC _o . Data from terminals with different communication speeds is transferred through one communication channel of the communication channel band corresponding to the speed.

The usage rate of each communication channel band of the data path _S1 changes randomly, but in the present invention, this is monitored by a usage rate monitoring means, for example, the usage rate monitoring circuit 2, and when a specific communication channel band is congested, the processing unit In step 4, a decision is made to change the communication channel band allocation, and the control signal transmitting/receiving circuit 3 is activated to send and receive a communication channel band change signal between exchanges A and B via signal path _S2 , and synchronization is established between both exchanges. This is to change the communication channel band of the data path _S1 .

FIG. 3 shows an example of a sequence in which exchanges A and B change channel band allocation via signal path _S2 . The sequence shown in FIG. 3 is an example of changing channel band allocation from exchange A to exchange B. In order to avoid simultaneous assignment change requests between both exchanges, exchange A is given priority in channel band assignment change control.

Switch A monitors the usage rate of each communication channel band, and when it is determined that it is necessary to change the allocation of communication channel bands, for example, the low-speed communication channel band
LCB is congested and therefore medium speed communication channel band
When attempting to change the allocation of one or more communication channels of the MCB, for example two communication channels MC _n-1 and MC _n , to the low-speed communication channel band LCB, the processing device 4 of the exchange A controls the control signal transmission/reception circuit 3. From there, a communication channel allocation change request signal a is sent to exchange B via signal path _S2 . At this time, the communication channels MC _n-1 and MC _n , which are subject to the above-mentioned allocation change, are blocked to prevent allocation to a new call. This situation is shown in Figure 31.
Shown below. This signal a is information for changing communication channel bands, that is, in the above case, medium speed communication channels MC _n-1 and MC _n are changed to low speed communication channel bands.
Contains information to change allocation to LCB.

In exchange B, the communication channel allocation change request signal a is received by its control signal transmitting/receiving circuit 3 and transferred to its processing device 4. Based on the signal a, the processing device 4 selects the change request channel, in the above case, the medium speed communication channel MC _n-1 and
Check if MC _n is in use.

Furthermore, if the corresponding communication channel is not used, that is, if it is empty, change and assign the corresponding channels MC _n-1 and MC _n to a low-speed communication channel,
This changed low-speed communication channel is incorporated into the low-speed communication channel band, and after this, the processing device 4 controls the control signal transmission/reception circuit 3 and sends a change completion signal b to the exchange A via the signal path _S2 . to be sent back.

When exchange A receives the above signal b,
The medium-speed communication channels MC _n-1 and MC _n are changed and assigned to low-speed communication channels, the above-described blockage is released, and the change processing is completed.

When exchange B receives the above signal a from exchange A, if the change request channel is in use, that is, it is blocked, it sends an in-use signal c to exchange A to that effect, as shown in FIG. 3. At the same time, the change request channel is blocked and the end of the call using the channel is monitored by setting a certain timing. During this set timing, if the change request communication channel ends all calls through it and becomes free, it will detect the free space and immediately change the communication channel band and remove the blockage. and sends a change completion signal b to exchange A.

When exchange A receives the change _completion signal b, it operates in the same manner as in the case of _FIG . Change the communication channel band and release the blockage.

Figure 3 shows the sequence when the change request channel does not become empty within the set timing after sending the busy signal c in exchange B.
Shown below. That is, as shown in the figure, when exchange B receives the communication channel allocation change request signal a from exchange A, if the change request channel is not free, as in the case of Fig. 3, exchange B is in use. Send signal c. However, unlike the case in FIG. 3 2, the change request channel does not become vacant during this set timing, so exchange B sends a change disable signal d back to exchange A and unblocks the change request channel. do. When exchange A receives the change prohibition signal d, it unblocks the already blocked change request channel. In this case, the communication channel allocation is not changed.

Note that the change in the allocation of communication channel bands is not limited to changing from the medium-speed communication channel band to the low-speed communication channel, but can also change from any communication channel band to any other communication channel band.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made within the technical scope thereof.

In the above embodiment, the usage rate of each communication channel band of the data path _S1 was monitored by the usage rate monitoring circuit 2, but other means, ie, in FIG.
Of course, it is also possible to monitor it in the processing device 4 that controls the connection between exchanges A and B, and by doing so, special hardware is not required as a usage rate monitoring means.

In the above embodiment, the communication channel allocation change is postponed while the change request communication channel is in use, but a call using the change request communication channel is reconnected to a communication channel for which no change request has been made, It is possible to force the change request channel into an empty state and then change the communication channel allocation in the manner described above.

Furthermore, although the above embodiments have shown the process of changing the allocation of communication channel bands between exchanges, even if one of the exchanges is a line concentrator, that is, the line concentrator and the time-division line switch can perform time-division multiplex communication. The present invention can also be applied to the case where the communication channels are connected by a channel, and the allocation of the communication channel band can be changed in the same manner as described above.

According to the present invention, as described above, when connecting exchanges or a concentrator and a switch using a time division multiplex communication path, each speed of the data path constituted by the time division multiplex communication path is By monitoring the traffic for each communication channel band, it becomes possible to automatically allocate communication channel bands that match the traffic situation at the time, without allocating personnel. The invention can be expected to automatically prevent delays in switching processing due to traffic concentration on a channel band of a specific speed and prevent invalid calls, etc., without any manual operation.
This has the effect of providing an economical communication line.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing connections in one embodiment of the present invention, FIG. 2 is a diagram showing an example of the configuration of a communication channel band for each speed of a data path, and FIG. 3 is a block diagram showing connections in an embodiment of the present invention. FIG. 3 is a diagram showing an operation sequence. A, B...Time division line exchanger, 1...Time division switch, 2...Utilization rate monitoring circuit, 3...Control signal transmission/reception circuit, 4...Processing device, _S1 ...Data path,
S ₂ ...Signal path, HCB...High speed communication channel band, MCB...Medium speed communication channel band, LCB...
Low-speed communication channel band, HC ₁ to _{HC l} ... High-speed communication channel, MC ₁ to _{MC n} ... Medium-speed communication channel, LC ₁ to _{LC o} ... Low-speed communication channel, a...
Communication channel allocation change request signal, b...change completion signal, c...in use signal, d...change not possible signal.

Claims (1)

[Claims] 1. In a time-division circuit switching system that has a data path that accommodates terminals with different communication speeds and carries time-division multiplexed data sent from the terminals, the communication channel of the data path is divided into speed-based communication channel bands. The switching equipment is provided with means for monitoring the usage rate of each speed-based communication channel, and the allocation of the communication channel band is automatically changed in accordance with the traffic condition based on the monitoring result of the monitoring means. Communication channel control method.