JPH05327868A - Multi-link control system - Google Patents

Abstract

PURPOSE:To build up an inexpensive network corresponding to traffic fluctuation and line fault by using a bypass line based on a subscriber number accommodated in a public telephone line. CONSTITUTION:Plural communication lines include bypass lines I1, I2 i1-i3 via a public telephone line (or ISDN exchange network line) C1 and an exchange A0 makes exchange connection by using a network management equipment B0 as a registration means registering a subscriber number accommodated in a communication line under its ow multi-link and the public telephone network line C1 of a bypass line of the relating multi-link and using the bypass line selected based on the content of the network management equipment B0 when a private line SI(S2, S3) is not in use. In this case, the private line S1 and the bypass line I1 are accommodated in the multi-link M1, the private line S2 and the bypass line I1 are accommodated in the multi-link M2, and the private line S3 and the bypass line I1 are accommodated in the multi-link M3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in a multilink control system for a switching system composed of a plurality of packet switches. In particular, the present invention relates to a multi-link control system that uses, as a multi-link, a bypass line passing through a public telephone network line or an ISDN line network in addition to a dedicated line.

[0002]

2. Description of the Related Art Conventionally, the multilink control system is a multilink internal line because the ground of the multilink (according to CCITT Recommendations X.25 and X.75) used as a line between packet switches is fixed. A dedicated line is used in.

Also, in a switching system constructed assuming maximum traffic on a line, the capacity of a dedicated line is not always effectively used.

Further, if the routes for laying the leased lines are the same, it is possible that failures will occur at the same time. When using the above-mentioned multilink as a means for avoiding such line failures, measures such as providing another route are taken. Need.

[0005]

In such a conventional multilink control system, the dedicated line in the multilink used as the line between the packet switches in the switching system is fixed even if the traffic is low. There was a problem that had to stay connected to.

Further, when the packet exchanges are scattered over a wide area, the number of dedicated lines connecting to the packet exchanges and the cost are large, the probability of encountering a line failure is high, and the network operation of the exchange system is not easy. There was a problem.

The present invention solves the above problems.
It is an object of the present invention to provide a multi-link control method that can cope with traffic fluctuations and line failures and can construct an inexpensive network.

[0008]

A first aspect of the present invention is a multilink control system including packet switches of a main station and a subordinate station for switching connection using a dedicated line as a plurality of communication lines constituting a multilink. In the above, the plurality of communication lines include a bypass line passing through a public telephone network line, and the packet switch of the main station is connected to the communication line under its own multilink and the public telephone network line of the opposing multilink bypass line. A registration means for registering the accommodated subscriber number and a detour for making a switching connection to the packet switch of the dependent station by using the detour line selected based on the contents of the registration means when the dedicated line cannot be used. And means.

Further, according to the present invention, the detour line is composed of one detour line group including a plurality of detour lines, and the registration means respectively registers a plurality of detour lines included in the one detour line group. The detour means may include means for selecting an empty detour line from the plurality of detour lines based on the contents of the registration means when the dedicated line cannot be used.

A second aspect of the present invention is a multilink control system provided with a plurality of packet switches for performing switching connection using dedicated lines as a plurality of communication lines constituting a multilink, wherein the plurality of communication lines are public telephones. Each of the plurality of packet exchanges includes a bypass line passing through a network line, and each of the plurality of packet switches registers the subscriber number accommodated in the communication line under its own multilink and the public telephone network line of the opposing multilink bypass line. The present invention is characterized by including registration means and detour means for performing switching connection using the detour line selected based on the contents of the registration means when the dedicated line cannot be used. Further, in the first invention and the second invention, the plurality of communication lines may include a bypass line passing through an ISDN line switching network line instead of the public telephone network line.

[0011]

[Function] A plurality of communication lines include a bypass line passing through the public telephone network, and are accommodated in the communication line under the own multilink registered when the leased line cannot be used and the opposing multilink public telephone network line. By using the bypass line based on the subscriber number, it is possible to cope with traffic fluctuations and line failures, and to construct an inexpensive network. In addition, the detour line is made into one detour line group including a plurality of detour lines, each detour line is stored, and when the leased line cannot be used, one free detour line is used among the plurality of detour lines. As a result, it is possible to easily add or reduce detour lines and reduce contention with other multilinks.

[0012]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a multilink control system according to the first embodiment of the present invention.

In FIG. 1, the multilink control system is
Switch A0 and a packet switch of a subordinate station as a packet switch of the main station for switching connection using dedicated lines S1 (s1) to S3 (s3) as a plurality of communication lines constituting multilinks M1 to M3 and m1 to m3. As exchange A1
To A3.

A feature of the present invention is that the plurality of communication lines are bypass lines I1, I2, i1 to i1 passing through a public telephone network line (or ISDN line switching network line) C1.
The exchange A0 includes a network serving as a registration means for registering a subscriber number accommodated in a communication line under its own multilink and a public telephone network line (ISDN line switching network line) C1 of a detour line of the opposing multilink. The management device B0 and means for performing switching connection by using the bypass line selected based on the contents of the network management device B0 when the leased line S1 (S2, S3) cannot be used.

Here, a multilink M1 and a multilink m1 are provided between the exchange A0 and the exchange A1, a multilink M2 and a multilink m2 are provided between the exchange A0 and the exchange A2, and a further exchange A0 and the exchange are provided. A3 is connected to A3 by a multilink M3 and a multilink m3.
The private line S1 and the bypass line I1 are provided for the multilink M1, and the private line S2 and the bypass line I are provided for the multilink M2.
1 and the multilink M3 accommodates the private line S3 and the detour line I1. The private line s1 and the alternate line i1 are connected to the multilink m1, and the private line s2 and the alternate line i2 are connected to the multilink m2.
Dedicated line s3 and detour line i3 are accommodated in 3. The detour lines I1 and i1 to i3 are detour lines that allow only incoming calls. Detour lines I1, i1 to i3 are network control units (NCU)
It is connected to a public telephone network line (ISDN line switching network line) C1 via a built-in modem or a terminal adapter.
The multi-links M1 to M3 are registered by the network management device B0. In this case, when the detour line I1 is registered as the multi-link subordinate line, the public telephone network line (ISDN) of the opposing multi-link detour lines i1 to i3 is registered. The subscriber numbers D1 to D3 accommodated in the circuit switching network line C1 are also registered.

The operation of the multilink control system having such a configuration will be described.

In FIG. 1, for example, when the switching system is servicing, the switching system is a private line S1.
If the multilink M1 detects the fault (s1),
Multilink M1 selects the detour line I1 in the empty state,
The subscriber number D1 of the detour line i1 accommodated in the opposing multilink m1 of the multilink M1 is sought and connected.

When congestion is detected between the multilink M2 and the multilink m2 at this time, the multilink M2 also selects the detour line I1 in the same manner as described above.
Since the detour line I1 is in use, waiting is performed for a predetermined time and the detour line is vacant. After the meeting, if the detour line I1 becomes empty, call and connect. If the detour line i2 cannot receive the call due to a failure or the like, the call is retried after a predetermined time. However, the number of retries is the specified number. Multilink M3 and Multilink m
The same applies to 2 and above.

The detour line I1 is released when the leased line is recovered from the failure and the multilink congestion is recovered.

FIG. 2 is a block diagram of a multilink control system according to the second embodiment of the present invention, in which A0A represents an exchange,
I0 indicates a detour line group including a plurality of detour lines I1 and I2, and B0A indicates a dedicated line under its own multilink, a detour line group I0 including the detour lines I1 and I2, and a public telephone of an opposing multilink detour line. It is a network management device for registering a subscriber number accommodated in a line (ISDN line switching network line) C1.

In FIG. 1, since one detour line is shared by a plurality of multilinks, it is possible to compete with other multilinks when detouring due to a line failure or traffic fluctuation. In addition, due to the limitation of the number of lines that accommodate the multilink, the probability of encountering competition increases depending on the system, and as a result, a large number of different detour lines are required for each multilink. In order to solve the above-mentioned problems, this embodiment accommodates a group of detour lines accommodating a plurality of detour lines as a line forming a multilink. In FIG. 2, when the switching system is servicing, for example, the switching system uses the private line S1 (s1).
When the multi-link M1 detects the line failure of the above, the multi-link M1 selects the detour line I1 in the empty state from the detour line group I0, and selects the detour line i1 accommodated in the multi-link m1 opposite to the multi-link m1. Subscriber number D1
To call and connect.

At this time, when congestion is detected between the multilink M2 and the multilink m2, the multilink M2 also selects an empty detour line I2 from the detour line group I0 as in the above. Call and connect to the detour line i2 of the opposing multilink m2.

Further, when a fault or congestion of the leased line S3 (s3) is detected between the multilink M3 and the multilink m3 as well, the detour line group I0 is selected in the same manner as described above. Detour line I1 in the detour line group I0,
Since I2 is in use, it waits for a predetermined time and waits for an empty line in the detour line group I0.
After waiting, if any line becomes available, use that line to make a call and connect.

FIG. 3 is a block diagram of a multilink control system according to the third embodiment of the present invention. While FIG. 1 shows a configuration of a master station and a dependent station, FIG. 3 shows exchanges A11 to A13.
Both cases are composed of the main station.

Detour line I11 accommodated in exchange A11
Are accommodated in the multilinks M13 and M12, the detour line I12 is accommodated in the multilinks M21 and M23, and the detour line I13 is accommodated in the macchilinks M31 and M32.

The bypass line I11 is a bypass line I12, I1.
It is possible to connect to 3 and for this purpose a multilink M1
The subscriber numbers D12 and D13 of the detour lines I12 and I13 accommodated in the ISDN circuit switching network line C1 accommodated in the multi-links of M3 and M12 are stored in the exchange A11. Similarly, the exchange A12 stores the subscriber numbers D11 and D13 of the detour lines I11 and I13, and the exchange A3 stores the subscriber numbers D11 and D12 of the detour lines I11 and I12.

In such a switching system, when the multilink M13 detects a line failure or congestion of the leased line S13, the detour line I11 is used.
By connecting with 13, the multi-link function is realized.
In the detour line I13, the originator number notifying means of the ISDN discriminates where the detour is made from when the call arrives, and provides a security function as a countermeasure against malicious calls. In this state, if the multilink M12 attempts to make a detour using the detour line I11, the detour line I11
Is already in use, the request is queued.

[0028]

As described above, the present invention has the excellent effect of being able to cope with traffic fluctuations and line failures and constructing an inexpensive network. In addition, by setting the subordinate lines that make up the multilink as a bypass line group,
It is easy to add or delete as needed, and it is possible to reduce conflicts during detours and improve communication connection quality.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a multilink control system according to a first embodiment of the present invention.

FIG. 2 is a block configuration diagram of a multilink control system according to a second embodiment of the present invention.

FIG. 3 is a block configuration diagram of a multilink control system according to a third embodiment of the present invention.

[Explanation of symbols]

A0, A1, A2, A3, A11, A12, A13, A
0A Switch B0, B11, B12, B13, B0A Network management device C1 Public telephone network line (ISDN circuit switched network line) D1, D2, D3, D11, D12, D13 Subscriber number I0 Detour line group I1, I2, I11, I12, I13, i1, i2, i
3, detour lines M1, M2, M3, M12, M13, M21, M23,
M31, M32, m1, m2, m3 Multilink S1, S2, S3, S12, S13, S21, S23,
S31, S32, s1, s2, s3 dedicated line

Claims (4)

[Claims] 1. A multilink control system comprising a packet switch of a main station and a subordinate station for switching connection using a dedicated line as a plurality of communication lines constituting a multilink, wherein the plurality of communication lines are public telephones. The packet switch of the main station, including the bypass line passing through the network line, registers the subscriber number accommodated in the communication line under its own multilink and the public telephone network line of the opposing multilink bypass line. A multi-function device comprising: a registration means and a detour means for making a switching connection to the packet switch of the dependent station by using the detour line selected based on the contents of the registration means when the dedicated line cannot be used. Link control method. 2. The detour line is composed of one detour line group including a plurality of detour lines, and the registration means includes means for respectively registering a plurality of detour lines included in the one detour line group, The detour means includes means for selecting an empty detour line from the plurality of detour lines based on the contents of the registration means when the dedicated line cannot be used.
The described multilink control method. 3. A multilink control system comprising a plurality of packet switches for switching connection using a dedicated line as a plurality of communication lines constituting a multilink, wherein the plurality of communication lines pass through a public telephone network line. Including a bypass line, each of the plurality of packet switches is a communication means under its own multilink and a registration means for registering a subscriber number accommodated in the public telephone network line of the opposite multilink bypass line, A multi-link control system comprising: detour means for performing switching connection using the detour line selected based on the contents of the registration means when the dedicated line cannot be used. 4. The multilink control system according to claim 1, wherein the plurality of communication lines include a bypass line passing through an ISDN line switching network line instead of the public telephone network line.