JPH08242241A - Method for selecting busiest group in atm exchange - Google Patents

Abstract

PURPOSE: To improve the connection rate of a wide band call by selecting a line as a storing destination when the line is a storable, and when the line is not storable, successively retrieving a storable line in predetermined order to select the storable line. CONSTITUTION: A line selection processing part 12 selects a storable line based upon a selection request and returns the selected result to a call processing execution controlling part 11. The processing part 12 applies line state collection for line selection to a line state managing part 13. The managing part 13 manages the total band capacity of lines, the application capacity of each line, etc., and when necessary, collects information from hardware through the hardware and an interface. The processing part 12 requests a call reception controlling part 14 to judge whether a call to a specific line can be stored or not and obtains its judged result. The controlling part 14 obtains information related to the application state of the line from the managing part 13, judges a final result of storage availability and returns the result to the processing part 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to line selection in call connection processing of ATM switch software, and more particularly to a method of selecting a most frequent group of ATM switches for improving connection of broadband calls in a multiple speed network. It is a thing.

[0002]

2. Description of the Related Art As a way of thinking about line selection, there are a method of accommodating calls in a distributed manner in each of the lines to be selected, and a method of accommodating calls in a part of lines. The former is effective in increasing the reliability of the network by distributing the load. On the other hand, the latter is effective in improving the call connection rate in a multi-speed network, and examples include the most frequent group selection and the fixed order selection.

The most busy group selection is a method of selecting accommodable lines by making a decision as to whether accommodation is possible or not in the order in which the lines are crowded (in ascending order of available bandwidth) from the lines to be selected. The feature is that narrow-band calls can be accommodated in a line with a high accommodation rate, so that a large free capacity can be secured in another line for connection of wide-band calls. The fixed order selection is a method of always determining whether accommodation is possible in a fixed order and selecting a line that can be accommodated.
Although the judgment is not always made from the side with the highest accommodation rate due to the accommodation or release of calls, statistically, the higher the accommodation rate, the higher the accommodation rate becomes for the line that first determines whether or not it is possible to obtain an effect close to that of the most busy group selection. In addition, since both systems increase the line capacity, efficient use of resources can be achieved.

On the other hand, in both systems, since the accommodation availability judgment is made in order from the busiest line or the busiest line, it is often impossible at the first accommodation availability judgment. If it becomes higher, the accommodation determination will be repeated. Bandwidth usage before accommodating is required to determine whether or not accommodation is possible, and it is necessary to inquire about the status of the line status management function and receive responses. In particular, when the hardware is responsible for part of the bandwidth management function, it takes time to understand the situation. Furthermore, in selecting the busiest group, since it is necessary to search for the busiest line, it is necessary to grasp the usage statuses of all the lines before making a decision.

In addition, the repetition of the accommodation decision and the search for the busiest line in the busiest group selection also increase the load in terms of call processing capacity, and ultimately an obstacle for increasing the call processing throughput. Becomes

[0006]

When the busiest group selection is realized by the line selection process, the load on the call processing time and the load on the call processing capacity by repeatedly grasping the line usage status and the selection of the busiest line are performed. The load on the call processing capacity of the device becomes a problem. An object of the present invention is to improve call processing throughput by improving these.

[0007]

A line designated for centrally accommodating calls is designated as a specific line. For connection request,
By accommodating calls to this specific line intensively, the busiest state is created, and the load required for grasping the line usage status and searching for the busiest line, which is the feature of the busiest group selection, is reduced. Also,
When a call that cannot be accommodated in the specific line occurs, the line that can accommodate the connection request call is searched by searching for the line that can be accommodated in order from the line with the oldest selection history (the largest free bandwidth due to release of the call). Search early. The line that accommodates this call is the specific line for the next call. If the line cannot be accommodated, the specific line will not be changed.

[0008]

[Function] It becomes unnecessary to search for the busiest line in the busiest group selection. This eliminates the waiting time required for inquiring the line usage status of all lines. In addition, when accommodating to a specific line is not possible, it is possible to repeat accommodative judgment by sequentially selecting from the line that has the statistically largest free bandwidth capacity (the line with the oldest selection history). The waiting time for grasping and the processing load can be improved.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the line configuration between the exchanges. Calling side exchange 1
0 receives a connection request from the user or the preceding stage exchange,
It is an exchange that carries out line selection based on this. Further, the destination exchange 20 is the exchange selected by the originating exchange 10 as the connection destination of the call (however, when both exchanges perform the processing with the line selection right, the destination exchange 20).
May also carry out the line selection). In this embodiment, four lines are set as the selection target lines 30 between the exchanges. The originating exchange 10 manages the line state (total line capacity and accommodated capacity) for each of these lines, and line selection is performed based on this capacity.

FIG. 2 shows each function realizing means related to the line selection processing. The call processing execution control unit 11 executes and manages connection processing according to the type of call. Here, after the destination exchange 20 is determined based on the connection request, the line selection processing unit 1
Requests line selection from 2. Line selection processing unit 12
Then, a line that can be accommodated is selected based on the selection request, and the result is returned to the call processing execution control unit 11.

In the line selection processing of the line selection processing unit 12,
The line state management unit 13 collects the line state for selecting the line. The line status management unit 13 manages the total bandwidth capacity, used capacity, etc. of the line, and collects information from the hardware through an interface with the hardware if necessary. The line selection processing unit 12 determines whether or not the call can be accommodated in the specified line by the call admission control unit 1.
Request 4 and get the result of acceptance. The call admission control unit 14 obtains information on the usage status of the line from the line status management unit 13, determines whether or not the line is finally accommodated, and returns the result to the line selection processing unit 12.

FIG. 3 shows an example of line selection according to the embodiment of the present invention. The horizontal bar graph in the figure represents the total bandwidth capacity and the used / unused bandwidth capacity for each line. For each line, the part that uses bandwidth as a result of call accommodation is shown in black, and the part that can accommodate a new call is shown in white. When a new call is accepted, the bandwidth used increases to the right, and when the call is released, it decreases to the left. Here, the description will be made assuming that each line has the same band capacity (actually, the capacities of the lines may be different, and it is necessary to consider different speed communication in the vertical direction).

FIG. 3A shows the band use status of each line before accepting the connection request call. The line 3 is designated as the specific line. This is based on the premise that the line 3 was the one that succeeded in accommodating the call immediately before.

FIG. 3B shows a state in which calls are continuously accommodated in a specific line (line 3). If there is a connection request in the state of (a), it is first judged whether or not the line 3 can be accommodated. If the judgment result is accommodating, there is no change in the specific line, and the accommodating / disallowing condition of the line 3 is similarly determined for the next connection request call. Repeated accommodating to line 3
The bandwidth used capacity of the network is increased, and the bandwidth used capacity is reduced because calls are released on other lines during this period.

FIG. 3C shows the change of the specific line.
When the connection request call cannot be accommodated in the line 3, the lines are selected in order from the oldest line selection history. In this embodiment, since the line numbers are selected in order, the next line 4 has the oldest selection history. Therefore,
This line 4 is selected. Whether or not the line 4 can be accommodated is determined, the call is accommodated because the line can be accommodated, and thereafter, the line 4 is set as a new specific line.

FIG. 3D shows a state in which calls are continuously accommodated in a specific line (line 4). Similar to (b), the call is accommodated until the line 4 is fully accommodated, and when a call that cannot be accommodated occurs, the line 1 having the oldest line history is moved to determine whether or not the line can be accommodated.

FIG. 4 shows a line selection processing flow in the outgoing connection processing. As the outgoing connection processing, the process from the outgoing connection request to the transmission of the capture signal to the outgoing exchange side opposite exchange is shown. In the figure, S
1 is a route selection step, S2 is a specific line setting step, S3 is a specific line selection step, S4 is a usage status investigation step, S5 is a bandwidth capacity comparison step, S6 is a capacity determination step, and S7 is A step of securing resources, a step S8 of sending a line capture signal, a step S9 of judging whether all lines have been judged, and a step S10 of selecting a next line.

In this embodiment, first, the route on the outgoing connection side is selected (S1). Here, the lines that can accommodate the connection request call are narrowed down to the route unit (transmission line unit or opposite exchange unit). Next, the specific line is clarified (S2). The specific line is the line that succeeded in accommodating the call last. In the first line selection, it is determined whether or not the particular line can be accommodated (S3, S4, S5). If it is possible to accommodate by the judgment of accommodation possibility (S6), resources are secured (S6).
7) Send a line capture request signal to the opposite exchange (S)
8). If the line cannot be accommodated, if there is a line that has not been judged yet, the next line is selected from the oldest selection history (S9, S10), and the connection availability is judged. This process can be simplified by predetermining the line selection order.
If all lines cannot be accommodated, the process proceeds to the selection of another route.

[0019]

Since the present invention basically performs the same stowage accommodation as the selection of the busiest group, the effect of the selection of the busiest group is to improve the connection rate of broadband calls when the accommodation rate is high. Can be achieved. Also, because the processing time and processing load are reduced, the call processing throughput of the entire exchange can be improved. Furthermore, since the processing logic is simplified compared to the most frequent group selection, productivity improvement in software development can be expected.

[Brief description of drawings]

FIG. 1 is a diagram showing a line configuration for showing an embodiment of the present invention.

FIG. 2 is a functional block diagram related to line selection processing for implementing the present invention.

FIG. 3 is a diagram showing an embodiment of line selection to which the present invention is applied, by showing changes in band usage status of each line.

FIG. 4 is a diagram showing a flow of an exchange outgoing side connection process including the present invention.

[Explanation of symbols]

 10 Calling side exchange 11 Call processing execution control unit 12 Line selection processing unit 13 Line state management unit 14 Call admission control unit 20 Calling side exchange 30 Selection target line

Claims (1)

[Claims] 1. A line selection method in the case where there are a plurality of outgoing lines for a call connection request in an ATM exchange,
First, it is judged whether or not the line that succeeded in accommodating the call can be accommodated immediately before, and if the line can be accommodated, the line is selected as the accommodation destination. If the line cannot be accommodated, the line that can be accommodated is determined in a predetermined order. A most probable group selection method for an ATM exchange, characterized by sequentially searching and selecting a line that can be accommodated and not accommodating if there is no line that can be accommodated in the selected line.