JPH0795207A - Communication control system - Google Patents

Abstract

PURPOSE:To reduce construction for extending a communications network equipment according to the development of a communication service demand by making full use of the existing communications network equipment as much as possible by repeatedly operating bus re-arrangement in as short a period as possible. CONSTITUTION:When an obtained path is different from the existing path of a path 20, a controller l transmits a control signal through a control signal line 10 to communicating nodes 2-9 related with path switching, and executes the no-hit switching of the path 20 to an optimal path. At the time of the no-hit switching, the device 1 sets a preliminary path corresponding to the path 20 on the calculated optimal path by using the communicating nodes 2, 3, 7, 8, and 9. Next, the device 1 executes the no-hit switching of the path 20 to the preliminary path 21 by using the no-hit switching devices of the communicating nodes 2 and 9 being the switching end points of the path 29 to the preliminary path 21. Thus, a new path can be set between the communicating nodes 5 and 6 without extending the communication equipment by the re-arrangement of the path 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is used for path setting in a communication network. In particular, the present invention relates to a technique for relocating a path in a communication network capable of switching without instantaneous interruption.

[0002]

2. Description of the Related Art As a technique for switching a path, which is a bundle of communication channels set between communication nodes, without any interruption, for example, Tatsuno, Tokura, "Consideration of an uninterrupted path switching method in an ATM transmission network", IEICE Technical Report, CS90-47, 1
The one shown in October 990 is known. With this technology, switching back the path or transmission line after failure recovery,
Alternatively, it is possible to change the accommodation of transmission lines and paths without interruption.

[0003]

However, there is no known technique for relocating a path to an optimum path route for the entire communication network. For this reason, the route of each path is fixed to the route determined when the path is newly established, and the route is not changed except when a failure, accommodation change, or other abnormal situation is dealt with. For this reason, if the structure of the communication network or the demand for communication services changes over time, there may be a situation in which the intra-network route of the path is not optimal, and there is a problem that the communication network equipment cannot be effectively used. .

The present invention solves such a problem, and provides a communication control system capable of relocating paths without interruption in response to changes in the structure of communication networks and changes in demand for communication services. With the goal.

[0005]

A communication control system according to the present invention comprises a plurality of communication nodes connected to each other by a transmission line, and a path which is a bundle of communication channels is set between the communication nodes. In a communication control system in which a control device that manages and controls the routes of the above is connected to a plurality of communication nodes by control signal lines, an intra-network route corresponding to a change in the communication service demand or a change in the communication network structure for an existing path is The present invention is characterized by including a calculating means and a non-interruption switching means for switching the communication service carried by the existing path to the intra-network route calculated by the calculating means without any substantial interruption.

As the non-instantaneous interruption switching means, it is preferable to use the mechanism described in the documents of Tatsuno and Tokura mentioned above.

[0007]

[Operation] According to the change in the structure of the communication network due to the addition or removal of transmission lines and communication nodes, and the change in the communication service demand, the optimum path is newly calculated and the path is switched without interruption. The path is switched to the optimum path calculated by the calculation. Therefore, the path can be switched to the newly calculated path without interrupting the communication service carried by the path for a moment, and the optimality of the path can always be ensured. That is, it is possible to optimize the path arrangement without affecting the communication service already performed through the path.

[0008] Here, for example, if "optimization" is defined as "maximizing the number of communication services that can be provided by the same communication network equipment", according to the present invention, the maximum number of communication services can be provided by the same communication network equipment. It is possible to relocate to a path route that can provide communication service, and it is possible to efficiently use the communication network. Further, it is possible to minimize the amount of work for adding communication network equipment in response to the development of demand for communication services, and to significantly reduce communication network costs.

“Optimization” can be defined separately.
For example, when a plurality of paths are set in advance between two communication nodes, it can be defined as "maximizing the number of communication services that can be provided by different intra-network routes". . In that case, the path rearrangement can prevent disconnection of a plurality of paths when a transmission line failure occurs, and can also realize high reliability of the communication network.

[0010]

1 is a block diagram showing a communication network according to a first embodiment of the present invention. This communication network comprises a plurality of communication nodes 2-9 connected to each other by transmission lines 11-19,
A path, which is a bundle of communication channels, is set between the communication nodes 2 to 9, and the control device 1 that manages and controls the route of this path connects the plurality of communication nodes 2 to 9 to the control signal line 10.
Connected by. The feature of this embodiment is that the control device 1 is provided with means for calculating an intra-network route according to a change in communication service demand or a change in communication network structure for an existing path, The communication nodes 2 to 9 are respectively provided with non-interruption switching means for switching the carried communication service to the intra-network route calculated by the calculation means without any interruption.
FIG. 1 also shows a path 20 set by using the communication nodes 2, 3, 5, 6, 9 and the transmission paths 11, 13, 15, 17.

FIG. 2 is a diagram showing an example of path rearrangement.
An example of rearranging the path 20 when a new path needs to be set between the communication nodes 5 and 6 because a new communication service demand is generated between the communication nodes 5 and 6 in FIG.

When the demand for the communication service changes, the control device 1 considers the newly set path and considers the existing path 20 so as to provide as many communication services as possible.
A new optimum route is calculated for. Here, it is assumed that the route passing through the communication nodes 2, 4, 7, 8, and 9 has been calculated. As an algorithm for calculating the optimum route, for example, Toshiya Hadama, Satoshi Ohta, "Study on Virtual Path Route Control in High-Speed Burst Multiplexing Transmission System", 1988 Autumn Meeting of the Institute of Electronics, Information and Communication Engineers, B-264, 1988 9
The method described in the Moon can be used. The three algorithms described in this document are shown in FIGS.

When the obtained route is different from the existing route of the path 20, the control device 1 passes through the control signal line 10 and
Communication nodes related to path switching (2-9 in this case)
A control signal is transmitted to the path 20 and the path 20 is switched to the optimum path without any interruption. The non-instantaneous switching is performed as follows. First, the control device 1 sets the backup path 21 corresponding to the path 20 on the calculated optimum route using the communication nodes 2, 3, 7, 8, and 9 (see FIG. 2B). Next, the control device 1
Performs uninterruptible switching of the path 20 to the backup path 21 by using the uninterruptible switching means of the communication nodes 2 and 9 which are the switching end points of the path 20 and the backup path 21 (FIG. 2C). reference). By rearranging the path 20, a new path 22 can be set between the communication nodes 5 and 6 without adding communication equipment (see FIG. 2D), and the communication equipment can be effectively used.

In this embodiment, the rearrangement of one existing path has been shown for the sake of simplicity. However, by applying this method to a plurality of paths, the rearrangement of a plurality of paths can be similarly performed. .

The example of the operation according to the change of the communication service demand has been described above. However, even if the structure of the communication network is changed due to the addition or removal of the transmission line or the communication node, the failure or the like, the path corresponding to the situation is changed. Optimal relocation is possible.

FIG. 6 is a block diagram showing a communication network according to the second embodiment of the present invention. This communication network is a partial network 101-10.
It is divided into three, and the control devices 104 to 106 corresponding to each.
Equipped with. The control devices 104 to 106 are communication lines 107 to
They are connected via 109 and can communicate with each other. The control devices 104 to 106 respectively include the partial network 101.
In addition to managing the routes of the paths in 103 to 103 and rearranging the paths, the paths between the partial networks 101 to 103 are rearranged in cooperation with the communication between the control devices.

[0017]

As described above, the communication control system of the present invention makes it possible to make the most effective use of the communication network equipment and provide the maximum communication service. If path relocation is repeated in the shortest possible cycle, it is possible to use up existing communication network equipment to the maximum extent, and it is possible to reduce the construction work of communication network equipment in response to the development of demand for communication services. There is an effect that can greatly reduce.

[Brief description of drawings]

FIG. 1 is a block diagram showing a communication network according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an example of path rearrangement.

FIG. 3 is a flowchart showing a first example of a path layout calculation algorithm.

FIG. 4 is a flowchart showing a second example of a path layout calculation algorithm.

FIG. 5 is a flowchart showing a second example of a path layout calculation algorithm.

FIG. 6 is a block diagram showing a communication network according to a second embodiment of the present invention.

[Explanation of symbols]

 1, 104-106 Control device 2-9 Communication node 10 Control signal line 11-19 Transmission line 20 Path 21 Backup path 22 New path 101-103 Sub-network 107-109 Communication line

Claims (1)

[Claims] 1. A plurality of communication nodes connected to each other by a transmission path, a path which is a bundle of communication channels is set between the communication nodes, and a control device for managing and controlling the path of the path is In a communication control method in which a plurality of communication nodes are connected by control signal lines, a means for calculating an intra-network route for an existing path according to changes in communication service demand or changes in the communication network structure and the existing paths A communication control system, comprising: a non-instantaneous-interruption switching unit that switches an existing communication service to the intra-network route calculated by the calculating unit without substantially instantaneous interruption.