JPS581877B2 - Line concentration method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a communication path network configuration of a line concentrator.

The communication path network of a large-scale exchange has a multi-stage structure, but in a local exchange that accommodates subscriber lines, several concentrating stages are provided to converge subscriber lines with low usage rates.

The number of concentrating stages has been compared between one stage and two stages (see Research and Application Report, Vol. 20, No. 3), but the former is uneconomical because the call loss rate on the primary link increases.

For this reason, existing electronic exchanges (e.g. DEX-21 and DEX-A11 (refer to Research and Practical Application Report Vol. 23, No. 5)
), a two-stage line concentration format is adopted.

FIG. 1 is a diagram showing the configuration of a concentrator stage of a DEX-21 communication path network.

PA00 to PAn7 and PB00 to PBn7 are primary switches in which subscriber lines are accommodated in the vertical direction.

SA0 to SA7 and SB0 to SB7 are secondary switches, and OUT0 to OUT63 are terminals connected to the tertiary switch.

The primary and secondary switches are all 8x8 grids.

The primary switch has (n+1) 8×8 switches connected in duplicate, and serves as a switch for 8 incoming lines (n+1) and 8 outgoing lines.

In other words, the input line at the primary switch is 1/(n+1)
The lines are concentrated in

Furthermore, the output line of the secondary switch is double-connected to the output line of another secondary switch, which further concentrates the line to 1/2, and the line between the primary switch and the secondary switch is 1/(2(n+
1) Configure the line concentration stage of).

The concentrator stage of DEX-21 connects the communication path network of the configuration shown in Figure 1 to 1.
One network is configured using six, and one unit has a maximum of 32 networks.

That is, the number of subscribers accommodated per one network in DEX-21 is 4096 (n+1), and the constituent unit of the line concentration stage is 1zs (n+1) subscriber terminals.

At this time, the concentration ratio is 1/(2(n+1)).

Now, the communication path network configuration of the line concentrator will be explained next.

FIG. 2 is an example of the communication path network configuration of the line concentrator, with LC0,
LC1 is a line concentrator, OFC is an accommodation station, and SUB is a subscriber telephone.

In the format shown in FIG. 2a, a concentrator stage of the communication path network of the central exchange is taken outside the station and used as the communication path network of the concentrator.

On the other hand, Fig. 2b shows a format in which a new communication path network is added to the line concentrator, and in this case, when connecting to the communication path network of the accommodation station, the subscriber lines concentrated by the line concentrator LC0 are deployed again. Generally, a line concentrator LC1 shown in FIG. 2 is added.

This is because the line concentrator is not installed for all subscribers accommodated in the central exchange, but only for some subscribers.

In other words, subscriber lines that enter the central exchange through a line concentrator are used at a higher efficiency than other subscriber lines, resulting in variations in subscriber line usage rates, which makes it difficult to design the communication path network of the central exchange. It becomes difficult.

Furthermore, by adding the line concentrator LC1 shown in FIG. 2, the control device of the host exchange can perform switching operations without being aware of the line concentrator.

In Figure 2, when comparing the format of a and the format of b,
In a, the line concentrator stage of the central exchange is simply removed, and the increase in hardware due to the introduction of the line concentrator can be minimized.

On the other hand, since b requires new line concentrators LC0 and LC1, it is clear that a is an economical type.

However, when a line concentrator is constructed in the form shown in FIG. 2a, the scale of the line concentrator is limited to the minimum constituent unit of the line concentrator stage in the communication path network of the central exchange.

In the case of the DEX-21 shown in FIG. 1, the minimum constituent unit of the concentrator stage is the number of subscribers, 128 (n+1), as described above.

If the line concentration ratio is 8:1 (n=3 in this case), the minimum unit of the line concentrator is 512.

On the other hand, the effect of introducing a line concentrator is to reduce the number of subscriber lines by concentrating subscribers with low call rates outside the station, so the line concentrator must be installed as close to the subscribers as possible.

When the scale of the line concentrator is large, it can be applied to a subscriber group with many subscribers distributed in high density, but when a small group of subscribers is distributed over a wide area, the distance from the subscriber to the line concentrator is It becomes long, and a sufficient line concentration effect cannot be achieved.

Particularly in agricultural, mountain, and fishing villages, groups of several dozen subscribers are often distributed at intervals of several kilometers.

Furthermore, since the line concentrator is installed outdoors, it is difficult for the service provider to secure an installation location, so it is generally installed on a pole, in a manhole, or the like.

For this reason, there are large restrictions on the volume and weight of the device, and the scale of the line concentrator is also restricted from this point of view.

As explained above, the line concentration system in which the line concentrator stage of the call path network of a large-scale exchange is taken out has the following drawbacks.

The first drawback is that the scale of the line concentrator becomes large and it is not possible to achieve a sufficient effect of introducing the line concentrator for subscribers who are distributed over a wide area.

The second drawback is that the volume and weight of the concentrator become large, making it impossible to install it on a pole or using existing equipment such as a manhole.

An object of the present invention is to sufficiently reduce the scale of the concentrator without changing the form of the communication path network of the central exchange in order to eliminate these drawbacks.

This will be explained in detail below with reference to the drawings. FIG. 3 is a diagram showing one embodiment of the present invention, in which the communication path network of the central exchange is
This is an example of the configuration as shown in the figure.

In FIG. 3, the same symbols as in FIG. 1 represent the same things, CONC is a concentrator, and SL is a line.

CONC-A, CONC-B, CONC-C, CONC
-D, CONC is a line concentrator that accommodates the primary switch in the communication path network of the accommodating exchange, and CONC-E is a line concentrator that accommodates the secondary switch in the communication path network of the accommodating exchange.

That is, subscribers are CONC-A, CONC-B, CO
Accommodated in NC-C, CONC-D and CONC, C
Not accommodated in ONC-E.

Connections between each concentrator are made using subscriber lines so as to have the same configuration as the communication network of the central exchange.

For example, connect the outgoing line of PB07 to the incoming line of PB17,
One outgoing line of Bn7 is connected to each of SB0 to SB7.

Further, the scale of the line concentrator can be set arbitrarily.

For example, CONC-A in FIG. 3 accommodates one primary switch and has eight subscribers.

CONC-B has 16 subscribers and CONC-C has 24COs.
NC-D accommodates 32 primary switches, CONC accommodates an arbitrary number of primary switches, and the number of subscribers is also arbitrary.

If the scale is to be further reduced, CONC-A may be divided.

For example, when dividing the line into two, one concentrator is configured with 4x8 switches, and two concentrators with such a configuration make up 8 concentrators.
Make it a ×8 switch.

Furthermore, if the scale is to be increased, the number of switches constituting one line concentrator may be increased.

The configuration of CONC-E is also not limited to that shown in FIG. 3, and can be divided arbitrarily.

With such a configuration, the scale of the line concentrator can be arbitrarily designed without changing the communication path network of the central exchange.

As explained above, according to the present invention, a line concentrator of any size can be installed at any position on subscriber lines, and therefore subscribers who are distributed over a wide area and in small groups can be concentrated very efficiently. , can provide an economical line concentration method.

Furthermore, since it can be made smaller in scale, it can be installed on existing subscriber line equipment, such as telephone poles and manholes, and there is no need to secure new installation space when introducing a line concentrator, making it extremely easy to install.

Furthermore, since there is no need to make any changes to the communication path network of the central exchange, various problems associated with the introduction of line concentrators, such as changing the channel matching procedure and changing the communication path network configuration by redistributing call loss rates, etc., can be solved all at once. can.

This is advantageous when designing a new switch with the addition of a line concentrator in mind, as it allows the optimal design of the call path network, but it is especially advantageous when introducing a new line concentrator to a switch that is already in operation. is an essential condition.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a concentrator stage of a communication line network in an existing large-scale exchange, FIGS. 2a and b are block diagrams showing an example of the configuration of a concentrator, and FIG. 3 shows an embodiment of the present invention. It is a block diagram of a line concentration system. PA00~PAn7, PB00~PBn7, SA0~S
A7, SB0 to SB7...Switch matrix, OUT0 to OUT63...Terminal, LC0,
LC1, CONC... Line concentrator, SL...
...Subscriber line, SUB...Subscriber telephone, O
FC... Accommodation station switchboard.

Claims (1)

[Claims] 1. In a concentrating system in which the concentrator stages in the call path network of the accommodating central exchange are used as the concentrator's communication path network, a plurality of concentrators are prepared, and the concentrator's communication path network is used as the concentrator's communication path network. Configuring a link connecting a switch accommodating a subscriber line and a switch accommodating a subscriber line of another concentrator using lines between concentrators so as to have the same configuration as a concentrator stage in a network. A line concentration method characterized by