JPH0650916B2 - Distributed exchange trunk selection method - Google Patents

Description

The present invention relates to a trunk selection system in a distributed exchange.

[Prior Art] FIG. 4 shows a configuration of a trunk selection system of a conventional distributed exchange. However, in FIG. 4, only the structure of the exchange call control related to the present invention is described, and the part related to the communication path is omitted.

In the distributed exchange as shown in FIG. 4, the subscriber STAs are distributed and accommodated in a plurality of subscriber control processors PS _{1 to} PS _k in view of expansion of processing capacity and expandability, and the trunk TRK is reliable. In order to improve the property, a plurality of trunks heading to the same ground are distributed and accommodated in a plurality of trunk control processors PT _{1 to} PT _i . In this case, management of acquisition and release of the trunk TRK is performed by the trunk management memory T
Perform by M.

When one trunk control processor accommodates m trunks, the trunk management memory TM has a capacity of m bits, and m trunks T under the control of its own processor.
Subscriber control processor PS which holds the empty / closed state of RK
_1- Updates the trunk management memory TM according to the acquisition / release request from PS _k .

Subscriber S accommodated in the subscriber control processor PS ₁
The TA outgoing connection process is performed as follows.

The subscriber control processor PS ₁ selects one processor from a plurality of trunk control processors (provisionally PT ₁ ), and the inter-processor network interface N
A trunk acquisition request is sent to the trunk control processor PT ₁ via the INF / interprocessor network.
Upon receiving this request, the trunk control processor PT ₁
The trunk management memory TM is searched for an empty trunk. If there is an empty trunk, the trunk management memory TM corresponding to this trunk is updated to the busy state, a trunk acquisition success message is returned to the subscriber control processor PS ₁ , and the trunk acquisition processing ends. If all the trunks in the trunk control processor PT ₁ are busy, the subscriber control processor PS ₁ receives the trunk acquisition failure message and again makes a similar acquisition request to the subscriber control processor PS ₂ as a bypass process. To do.

Thereafter, acquisition requests are sequentially issued to the trunk control processor until the trunk acquisition is successful, and if the trunk acquisition is not possible even if all trunk control processors are bypassed, the trunk is blocked and a busy tone is sent to the subscriber STA.

[Problems to be solved by the invention]

In the conventional trunk selection method described above, when the traffic becomes high and the usage rate of the trunk is increased, the detour processing is increased, the load of the subscriber control processor PS and the trunk control processor PT is increased, and the processing capacity of the entire exchange is increased. There is a problem of decrease.

An object of the present invention is to provide a trunk selection system for a distributed exchange that solves such problems.

[Means for solving problems]

To achieve the above object, the present invention provides a plurality of trunks distributed in a plurality of trunk control processors, and a plurality of subscribers distributed in a plurality of subscriber control processors. In a trunk selection system of a distributed switch for selecting a trunk in response to a request from the subscriber control processor, the trunk control processor holds a trunk management memory for holding an empty / busy state of the trunk in the self processor. , The trunk control processor, by the trunk selection,
A means for notifying all the other subscriber control processors that the trunks of the own processor are all in the busy state, and that the trunk of the own processor is no longer in the all busy state due to the release of the trunk. Means for notifying all the subscriber control processors of the above, the subscriber control processor is provided with an empty trunk existence memory for holding whether or not there is an empty trunk corresponding to the trunk control processor, The personal control processor updates the empty trunk existing memory with the information notified from the trunk control processor, and refers to the empty trunk existing memory to issue a selection request to the trunk control processor having the empty trunk. And have.

[Action]

According to the present invention, the trunk control processor is provided with the first memory for holding the empty / busy state of the trunk in the self processor, and the trunk control processor itself selects all the trunks by selecting the trunk. Notifies all the other subscriber control processors that it is in the middle state, and notifies all the other subscriber control processors that the trunk of the self processor is no longer in the busy state by releasing the trunk. Have a function.

On the other hand, the subscriber control processor is provided with a second memory that holds whether or not there is an empty trunk corresponding to the trunk control processor, and the information notified from the trunk control processor to the subscriber control processor itself, The second memory is updated, and the function of issuing a selection request to the trunk control processor having an empty trunk by referring to the second memory is provided.

As a result, the subscriber control processor can know the trunk control processor having an empty trunk when selecting the trunk.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing the configuration of an embodiment of the present invention. First
In the figure, the subscriber control processor _PS 1 _{~PS k,} trunk control processor _PT 1 _{~PT i,} network interface NINF between processors, the functionality of the trunk management memory TM is the same as the conventional example of FIG. 4.

The difference from the conventional example is that an empty trunk existence memory ITM is provided in each of the subscriber control processors PS _{1 to} PS _k . The empty trunk existence memory ITM has an i-bit capacity in a system having i trunk control processors PT, and each bit corresponds to the trunk control processor, and whether or not an empty trunk currently exists in the trunk control processor. Indicates

A control sequence when selecting a trunk in the embodiment of the present invention will be described with reference to FIG. The subscriber control processor PS ₁ searches the empty trunk existing memory ITM (step S1). If all the trunk control processors do not hold an empty trunk (step S2), trunk blocking processing is performed (step S4). If an empty trunk exists, the trunk control processor PT _i currently holding the empty trunk is known (step S2). Thereafter, a trunk acquisition request is sent to the trunk control processor PT _i via the inter-processor network interface NINF and the inter-processor network (step S3). Upon receiving the acquisition request, the trunk control processor PT _i searches the trunk management memory TM, selects one empty trunk, returns the accommodation position of the acquired trunk to the subscriber control processor PS ₁ , and at the same time, the trunk management memory TM. Is updated (step S
7). On the other hand, the subscriber control processor PS ₁ continues the outgoing call connection processing thereafter (step S5).

After updating the trunk management memory TM, the trunk management processor PT _i finds that there is no vacant trunk due to the current trunk capture (steps S8 and S9), and “the trunk of the own processor PT _i is busy”. Is sent to all subscriber control processors PS via the network interface NINF between the processors and the interprocessor network (step S10). Upon receipt of this message, the subscriber control processor PS receives an empty trunk existing memory I in its own processor.
The information corresponding to the TM trunk control processor PT _i is changed to the "trunk full busy state" (step S6). By this operation, the subscriber control processor PS ₁ knows that there is no empty trunk in the trunk control processor PT _i in the next trunk selection.
It is possible to avoid useless processing of issuing a trunk acquisition request to the trunk control processor PT _i .

Next, the control sequence when the trunk is released will be described with reference to FIG. The subscriber control processor PS ₁ transmits the accommodation position of the trunk to be released to the trunk control processor PTS _i (step S11). The trunk control processor PT _i updates the information corresponding to the trunk in the trunk management memory TM to the empty state by the procedure reverse to that at the time of capturing the trunk (step S12). Further, by this release processing, the processor checks whether or not the state in which all trunks are busy is changed to "a state in which there is only one empty trunk" (steps S13 and S14). In such a case, " A message stating that an empty trunk has occurred in its own processor PT _i is sent to all subscriber control processors PS via the interprocessor network interface NINF and the interprocessor network (step S15).

The subscriber control processor PS that received this message
Changes the information corresponding to the trunk control processor PT _i of the empty trunk existing memory ITM in its own processor to the “empty trunk existing state” by the procedure reverse to the processing at the time of capturing the trunk (step S16). By this operation, the subscriber control processor PS ₁ can issue a trunk acquisition request by designating the processor PT _i in which an empty trunk exists in the next trunk selection.

〔The invention's effect〕

As described above, according to the present invention, since the subscriber control processor can know the trunk control processor having an empty trunk when selecting the trunk, the invalid detouring process which has been a problem in the conventional example at the time of high traffic. Can be eliminated, and the processing capacity can be improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of the present invention, FIG. 2 is a diagram showing a sequence when a trunk is selected in the embodiment of FIG. 1, and FIG. 3 is a trunk release in the embodiment of FIG. FIG. 4 is a diagram showing the sequence of FIG. 4, and FIG. 4 is a diagram showing the configuration of a trunk selection system of a conventional distributed exchange. PS _{1 to} PS _k ...... Subscriber control processor PT _{1 to} PT _i ...... Trunk control processor NINF …… Interprocessor network interface STA …… Subscriber TRK …… Trunk TM …… Trunk management memory ITM …… Empty trunk existence memory

Claims (1)

[Claims] 1. A plurality of trunks are distributed in a plurality of trunk control processors, a plurality of subscribers are distributed in a plurality of subscriber control processors, and the trunk control processor is distributed in the subscriber control processor. In a trunk selection method of a distributed switch for selecting a trunk in response to a request from the trunk control processor, the trunk control processor is provided with a trunk management memory for holding an empty / busy state of the trunk in the self processor. By trunk selection,
A means for notifying all the other subscriber control processors that the trunks of the own processor are all in the busy state, and that the trunk of the own processor is no longer in the all busy state due to the release of the trunk. Means for notifying all the subscriber control processors of the above, the subscriber control processor is provided with an empty trunk existence memory for holding whether or not there is an empty trunk corresponding to the trunk control processor, The personal control processor updates the empty trunk existing memory with the information notified from the trunk control processor, and refers to the empty trunk existing memory to issue a selection request to the trunk control processor having the empty trunk. A trunk selection method for a distributed exchange, characterized by having: