KR950013174B1 - Multi-slot-call rearrangement method in time-space-time switching network - Google Patents

Abstract

comparing a time slot use state table of an internal highway in case of generating a call to request n time slots from a subscriber; searching the time slot of an idle state; changing the time slot of the idle state to the other time slot of the busy state in the internal highway time slot use state table; writing an input internal highway number in a time slot connection reference table; checking whether the multi-slot call is rearranged or not; if the rearrangement is needed, rearranging the multi-slot call; changing the time slot of the idle state to the time slot of the busy state obtained in the above step from the time slot use state table of the internal highway; recording the input internal highway number in the time slot connection reference table; if the rearrangement is failed in the above step, processing a call rejection; completing to set the multi-slot call by performing the above steps; maintaining the busy state during a predetermined time; in case that the subscriber requests a call release, changing the time slot of the busy state to the time slot of the idle state in the time slot use state table of the internal highway; erasing the time slot connection reference table; and completing the all operations.

Description

Multislot Call Rearrangement Method in Time-to-Time Exchange Networks

1 is a block diagram of a hardware system to which the present invention is applied.

2 is a software operation diagram according to the present invention.

3 is an overall flow chart in accordance with the present invention.

* Explanation of symbols for main parts of the drawings

1: Time-space-time switching network of double buffer configuration 2, 3: Time switch of double buffer

4: Time Multiplexing Space Switch 5, 6: Internal Highway

7 switch network control processor 8 switch network control function

9,10: Time slot use status table 11, 12: Temporary register

13: Timeslot Association Reference Table

The present invention relates to a method for accommodating a multi-slot call in a time-space-time (TST) switching network in a double buffer configuration. In particular, the present invention relates to a multislot call rearrangement method that applies a rearrangement method when searching a multislot call path.

In the Integrated Services Digital Network (ISDN), a multi-rate allocation of n timeslots for a call is required to accommodate medium-band services with bands of n × 64 Kbps (n≤32) as well as narrow-band services of 64 Kbps or less. Multi-rate circuit switching must be realized.

That is, H ₀ channels (384 Kbps, 6 timeslots) for video conferencing, H ₁₁ channels (1,536 Mbps, 24 timeslots) and H ₁₂ channels (1,920 Mpps 30 timeslots) for high-speed data services. Should be provided.

In the existing T-S-T switching network, a random call search method, a sequential call search method, or a periodic call search method is applied to each type of call to accommodate multiple slot calls. However, the above methods generally have a problem that the blocking probability is large for multislot calls, making it difficult to satisfy the quality of service and lowering the throughput of the entire switching network.

Accordingly, the present invention devised to improve the problems of the prior art is to apply the rearrangement method for the multi-slot call when mixed-single-slot call (voice call) and multi-slot call in the double buffer TST switching network Therefore, the purpose of the present invention is to provide a multi-slot call rearrangement method that satisfies the quality of service by reducing the hawthorn rate for the call and greatly improves the yield of the switching network.

In order to achieve the above object, the present invention compares the timeslot usage state table of the internal highways of the input / output side when the call requesting n timeslots from the subscriber or the incoming line is used to search for idle timeslots at the same time. After performing the first step and the first step, in the time slot use state table of the internal highway of the input / output side, the time slot searched in the first step and the idle state are busy and refer to time slot connection. A second step of writing an input-side internal highway number in a table; a third step of determining whether to perform a rearrangement process on the multislot call after performing the second step; and rearranging from the third step Is determined, the fourth step of performing the multi-slot call rearrangement process, and after the fourth step, the internal highway of the input / output side In the imslot use state table, a fifth step of changing a time slot which is obtained at the same time and in a dormant state into a busy state, and writing an input internal highway number in a time slot connection reference table; If it fails, the sixth step of performing a call-out process, and repeating the third to fifth steps to complete the multi-slot call setup and to maintain a busy state for a certain time, and performing the seventh step After receiving the call release request from the subscriber or the incoming line, an eighth step of changing the timeslot of the multislot call to a dormant state in the time slot use state table of the internal input / output side and deleting the timeslot connection reference table is completed. Is carried out.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention;

1 is a schematic diagram of a hardware system to which the present invention is applied, where 1 is a double buffered TST switching network, 2, 3 is a double buffered time switch, and 4 is a time-multiplexed switch. Space Switch), 5 and 6 represent an Internal Highway (IHW), 7 represents a Switching Network Processor (SNP), and 8 represents a Switching Network Control (SNC).

As shown in FIG. 1, the hardware system to which the present invention is applied consists of a T-S-T switching network 1 and a switching network control processor 7 having a double buffer configuration.

The double buffered TST switching network 1 includes a plurality of input double buffer time switches 2 and a plurality of output double buffer time switches 3 which perform an exchange function for each time slot, and the respective input / output time switches ( 2, 3, and a time multiplexing space switch 4 for spatially exchanging the time slots coming from each input side time switch 2 to each output side time switch 3, respectively.

The switching network control function unit 8 manages the entire T-S-T switching network 1 having a double buffer configuration, and performs a function of allocating and retrieving timeslots necessary for establishing or releasing a call.

2 is an operating state according to the present invention, 9 is a time slot use state table of the input side internal highway 6 (hereinafter referred to as "TSUST"), 10 is a TSUST of the output side internal highway 7, 11 is a multi-slot call Temporary register by setting (hereinafter referred to as "temporary register A"), 12 is a temporary register for re-exchange (hereinafter referred to as "temporary register B"), 13 is a time slot connection reference table (hereinafter referred to as "TSCT"). "," Respectively.

Referring to FIG. 2, a process of allocating a timeslot required for setting a currency using a multislot call rearrangement method is described below.

In the drawing, a call requiring two timeslots is generated for convenience, and one of the timeslots is searched by comparing the TSUST 9 of the input side internal highway (hereinafter referred to as “IHW”) and the TSUST 10 of the output side IHW. One time slot describes a case of searching using a multislot call rearrangement method.

The SNC compares the TSUST 9 of the input side IHW 1 and the TSUST 10 of the output side IHW 2 and simultaneously searches for an idle time slot. Since the time slots in the idle state are only time slots 3, the position information 3 is stored in the temporary register A11. In the TSUST (9, 10) of the input IHW 1 and the output IHW 2, the state of the time slot 3 is busy, and the input IHW number is assigned to the TSCT 13 corresponding to the time slot 3 of the output IHW 2. Write 1

Next, in order to find the remaining one timeslot by using the multislot call rearrangement method, the first time slot is searched in the TSUST 9 of the input side IHW1. Since the idle time slot is timeslot 1, the position information 1 is stored in the temporary register B 12.

The input side IHW number connected to the time slot 1 of the output side IHW 2 is found by reading the value corresponding to the position information 1 of the output side IHW 2 from the TSCT 13. Since the input IHW number is 3, the input IHW 3 becomes the switching input IHW.

The TSUST of the input side IHW 3, which is the re-exchange input side IHW, and the TSUST 10 of the output side IHW 2 are compared to search for a time slot in the idle state. At the same time, the idle time slot is timeslot 2, so the position information 2 is added to the temporary register B 12.

In the TSUST of the input side IHW 3 and the TSUST 10 of the output side IHW 2, the next re-exchange is performed using the two positional information stored in the temporary register B 12.

Then, in the TSUST of the input IHW 3 and the output IHW 2, the state of timeslot 1 corresponding to the first position information of the temporary register B 12 is changed from the busy state to the dormant state and the state of timeslot 2 corresponding to the second position information. Changes from idle to busy.

Then, the information of the TSCT 13 corresponding to the first position information 1 of the output side IHW 2 and the temporary register B 12 is stored in the TSCT corresponding to the second position information 2 of the output IHW 2 and the temporary register B 12. 13), the information of the TSCT 13 corresponding to the position information 1 of the first side of the output side IHW 2 and the temporary register B 12 is deleted. The first positional information 1 of the temporary register B 12 is added to the temporary register A 11. Therefore, in the TSUSTs 9 and 10 of the input IHW 1 and the output IHW 2, the time slots corresponding to the position information 1 become the time slots at the same time. Finally, in the TSUST (9, 10) of the input side IHW1 and the output side IHW2, the state of the time slot 1 is changed to a busy state, and the input side is input to the TSCT 13 corresponding to the time slot 1 of the output side IHW2. Write IHW number 1. Therefore, the call requesting the two timeslots is established by using the timeslots corresponding to the position information 3 and 1 of the temporary register at the input IHW 1 and the output IHW 2.

3 is a flow chart of a multi-slot call rearrangement method according to the present invention.

The multi-slot call rearrangement method according to the present invention realized by the SNC until the multi-slot call is generated and released is described with reference to FIG.

If a multislot call requiring n timeslots from a subscriber or incoming line occurs (21), the SNC compares the TSUSTs of the input internal highway and the output internal highway to search for idle time slots at the same time (22). At the same time, the position information of the time slots in the idle state is stored in the temporary register A (23).

In the TSUST of the input IHW and the output IHW, the busy state of the time slot corresponding to the position information stored in the temporary register A is busy, and the TSCT corresponding to the position information of the output IHW and the temporary register A is busy. Write down the number of the input IHW (24).

It is checked whether the number of location information stored in the temporary register A becomes n, the number of timeslots required for the multislot call (25). If n, the process proceeds to step 39 of releasing the temporary register B, which will be described later. If less than n, the next multislot call rearrangement process starts.

In other words, it is checked whether there is a idle time slot in TSUST of the input IHW (26). If there is no idle time slot, the temporary register B is released (27), and the TSUST of the input IHW and the output IHW changes the use state of the time slot corresponding to all position information stored in the temporary register A to the idle state. In the TSCT corresponding to the position information of the output IHW and the temporary register A, the number of the input IHW is deleted (28), and the temporary register A is released (29). Finally, the multi-slot call is rejected (30) and terminated.

If there is a time slot in the idle state as a result of the investigation in step 26, the position information of the time slot is stored in the temporary register B (31). The value corresponding to the position information stored in the output IHW and the temporary register B is read from the TSCT to find the input IHW (hereinafter referred to as "rechange input IHW") number to be used for reswitching (32).

Compare the TSUST of the re-exchange input IHW with the TSUST of the output IHW and search for a time slot in idle state at the same time (33). Ends with).

At the same time, if there is a time slot in the idle state, the position information of the time slot is added to the temporary register B (35). The next re-exchange is performed using the position information of the two timeslots stored in the temporary register B at the re-exchange input IHW and the output-side IHW (36). That is, in the TSUST of the reswitching input IHW and the output IHW, the state of the time slot corresponding to the first position information of the temporary register B is changed from the idle state to the idle state, and the state of the time slot corresponding to the second position information is the idle state. Change to The TSCT information corresponding to the first position information of the output IHW and the temporary register B is transferred to the TSCT corresponding to the output IHW and the second position information, and the values of the TSCT corresponding to the output IHW and the first side position information are deleted.

Then, the first location information stored in the temporary register B is added to the temporary register A (37). Then, in the TSUST of the input IHW and the output IHW, the state of use of the time slot corresponding to the position information added to the temporary register A is changed to a busy state, and the input side is input to the TSCT corresponding to the position information added to the output IHW and the temporary register A. Write down the IHW number (38). Then, the state now returns to the process of 25 to investigate if a further rearrangement process is needed for the multislot call.

On the other hand, as a result of performing step 25, if the number of location information stored in the temporary register A becomes n, which is the number of timeslots required by the multislot call, the temporary register B is released (39) and the call of the multislot call is made. The setting is completed (40). This maintains the busy state for a certain time (41).

Then, upon receiving the call release request from the subscriber or the incoming line (42), TSUST of the input IHW and the output IHW is re-used while the timeslots corresponding to the n position information stored in the temporary register A remain busy. After checking whether it has been exchanged, the state of use of the n appropriate timeslots is changed to the idle state and the value of TSCT corresponding to the appropriate location information is deleted (43). Finally, the temporary register A is released (44) and ends.

Therefore, according to the present invention performed by the above processing procedure, by applying the rearrangement method to the multi-slot call, the call loss rate is lowered for the call, thereby improving the quality of service and greatly improving the yield of the switching network. have.

In addition, if the multi-slot call rearrangement method is adopted in the design of the switching network, it is possible to efficiently use the resources (currency path) of the switching network, thereby reducing the cost in realizing the switching network.

Claims (3)

A plurality of input double buffer time switches (2) and a plurality of output double buffer time switches (3) which perform an exchange function for each time slot, and the respective input / output time switches (2, 3) are connected to each input. A double-buffered time-space-time (TST) switching network 1 having a time multiplexing space switch 4 for spatially exchanging time slots from the time switch 2 to the respective output time switches 3, In the multi-slot call rearrangement method comprising a TST switching network control processor (7); A first step (21, 22) of searching for idle time slots by comparing time slot usage state tables of input / output internal highways when a call requesting n timeslots from a subscriber or incoming line occurs; After performing the first steps (21, 22), the time slots used in the time slot use state table of the input / output internal highway are searched in the first step and the idle time slots are busy, and the time slot connection reference table is added. A second step (23,24) of writing an input internal highway number; and a third step of determining whether to perform a rearrangement process on the multislot call after performing the second step (23, 24) ( 25), if it is determined that rearrangement is necessary from the third step 25, the fourth steps 26 and 31 to 36 for performing the multi-slot call rearrangement process, and the fourth steps 25 and 31 to 36) After execution, internal I / O high A fifth step (37, 38) of changing the idle time slot obtained in the fourth step into a busy state in the time slot use state table and writing an input internal highway number in the time slot connection reference table; If the rearrangement fails in performing the steps 26, 31 to 36, the sixth step 27 to 30 and the third to fifth steps 25, 26, 31 to 38 are performed. Repeat the seventh step (39 to 41) to complete the multi-slot call setup and maintain a busy state for a predetermined time, and after performing the seventh step (39 to 41), the call request from the subscriber or incoming line And receiving an eighth step (42 to 44) of changing the timeslot of the multislot call to a dormant state in the timeslot use state table of the input / output internal highway and deleting the timeslot connection reference table. Multi-armed Arc rearrangement process of T-S-T-switching network, characterized in that the. 4. The method of claim 1, wherein the fourth steps (26, 31 to 36) comprise: searching for (26, 31) timeslots in the idle state in the timeslot usage table of the input highway (26, 31). Determining the reswitching input highway from the timeslot connection reference table after performing step 32. After performing step 32, the time slot usage status table of the reswitching input highway and the output highway is compared to perform the idle time. Searching for slots 33, after performing step 33, with respect to the timeslots obtained in steps 26 and 31 and 33, changing the state in the timeslot usage table and timeslots And a fourth step (34 to 36) of replacing information in the connection reference table. The method of claim 2, wherein the sixth step (27 to 30) of performing the abortion process includes the step (27) of releasing the temporary register B, and after the step (27), the time of the input highway and the output highway. In the slot usage table, change the usage state of the timeslot corresponding to all position information stored in the temporary register to the idle state, and delete the input highway number from the time slot connection reference table corresponding to the position information of the output highway and temporary register A. And rejecting and terminating the multi-slot call by releasing the temporary register (28 to 30).