JP3537017B2 - Communication network and logical path route selection method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in a communication system in which a logical path is semi-permanently set on a physical transmission path for communication. The present invention relates to SDH (Synchronous Digital Hierarchy)
Suitable for use on the net.

[0002]

2. Description of the Related Art In a conventional communication network for transmitting information by setting a logical path, which is a virtual transmission path, on a physical transmission path provided between a plurality of node devices, a logic set between the node devices is provided. All logical paths are handled without discrimination regarding maintenance, operation, and management such as accommodation design, setting, and recovery from failure in paths. Recovery from a failure is mainly performed by taking a redundant configuration for each link between adjacent node devices and switching the section (section). Recently, a system that performs switching in units of logical paths has also been realized. The logical path here is described in the document "ITU-T Draft Revied Recommendation G.70
X, "Network node interface for the synchronous digi
tal hierarchy (SDH), "Study Group 15, Geneva, Switzerl
and, Feb. 6-17, 1995. "
s Handles a semi-permanently set logical path like a Virtual Container (VC) in a Digital Hierarchy (SDH) network.

FIG. 11 is a conceptual diagram of a conventional communication network. Regarding the setting of a logical path, an operation system OpS that is separate from the node devices A to C stores a free capacity in each of the node devices A to C in a database. Optimized route search based on logical path opening request
The result is given to each of the node devices A to C,
ＣC to configure a logical path.

[0004]

As the telephone-based communication network shifts to a computer-based multimedia communication network, voice,
It is predicted that a wide variety of media information such as images and data will appear. Such media information is considered to have different requirements for transmission of such information, such as a transmission error rate, a recovery characteristic at the time of failure, a delay time, and a price. For this reason, it is necessary to provide a transport function corresponding to a request for media information to be transmitted even in a communication network for transmitting a logical path between node devices.

For example, highly reliable communication information is transmitted without dropping one bit even in the event of a failure, and communication information requiring economical efficiency is provided at a low price by reducing the failure recovery function. It is important to economically realize a communication network having a plurality of transport functions.

However, in the conventional communication network, since all the logical paths are treated without discrimination, it is difficult to configure an economical communication network by setting a plurality of transport functions to the logical paths as described above. . For example, in a conventional communication network in which recovery at the time of a failure is performed for each link between adjacent node devices, a logical path that prioritizes the price over the failure recovery function also has a recovery function, resulting in a rise in price. Invite. In addition, a logical path requiring high reliability cannot be recovered from a failure such as a complete link failure, so that a highly reliable logical path cannot always be provided.

On the other hand, regarding the setting of a logical path, conventionally, an optimum route is searched using an operation system separate from the node device, and the result is given to each node device. Connection has been made and route setting has been completed. For this reason, an individual operation system is required, and further, a connection device for connecting the operation system to each node device is required. Also, the layout of the node devices is designed based on a ladder network, and under the current situation where many logical paths exist between the node devices, a huge database is required for the logical path accommodation design. The construction of an operation system that maintains and manages the above-described logical paths having a plurality of transport functions requires more functions than before, and it is difficult to achieve economics. Although the transition to a ring network is progressing from the viewpoint of survivability, it is also difficult to economically implement the above-described operation system expansion to a ring network.

As described above, in order to economically realize a multimedia communication network, maintenance, operation, and management of a logical path having a plurality of transport functions are economically realized while considering the arrangement of node devices. You need a way to do that.

The present invention has been made in view of such a background, and an object of the present invention is to provide a communication network and a logical path route selection method capable of setting a route having a plurality of transport functions. SUMMARY OF THE INVENTION It is an object of the present invention to provide a communication network and a logical path route selection method capable of setting a route through which information can be transmitted without loss of information even when a failure occurs in highly reliable communication information. SUMMARY OF THE INVENTION It is an object of the present invention to provide a communication network and a logical path route selection method capable of setting a route capable of economically transmitting communication information that does not require reliability. An object of the present invention is to provide a communication network and a logical path route selection method that can easily configure a ring network.

[0010]

SUMMARY OF THE INVENTION The present invention relates to a communication network for setting and transmitting a logical path, which is a unit of information transmission, between node devices, wherein a logical path having different transport functions is minimized. It is characterized by providing a communication network managed by the number of paths and not requiring an individual operation system. The input / output of the node device may be an electrical signal, but in the case of optical communication connected by an optical fiber transmission line, the input / output unit also communicates via the photoelectric converter.

A first aspect of the present invention relates to a service class and the number of logical paths according to the transmission quality of a path set on a logical path, and includes a plurality of node devices connected by a physical transmission path. A communication network for setting and transmitting a logical path, which is a unit of information transmission, between other node devices, wherein a logical path between the node device and the target node device is distributed, for example, by a first path and a different path distribution. A logical path of an upper class (hereinafter, referred to as a class A) which sets the second route and switches the route without interruption upon a failure;
An intermediate class (hereinafter, referred to as class B) logical path for searching for a new path and rescuing an information signal in the event of a failure;
It is characterized by comprising only three logical paths of a lower class (hereinafter, referred to as class C) logical paths for recovering information signals by facility restoration without recovering information signals at the time of failure.

That is, by dividing the logical path between the target node devices into three classes according to the failure recovery performance, the transport function required from the service node side can be logically performed without taking a redundant configuration of sections. It can be secured at the path level, thus providing an economical communication network with reduced transmission equipment. Also, by managing only three large-capacity paths, the number of paths to be managed in the communication network can be reduced, and the load on the operation system can be reduced.

A second aspect of the present invention relates to an arrangement of node devices, in which a plurality of node devices connected by a transmission line are connected in a ring shape, and a plurality of the ring networks are arranged in a plane. Ring networks are connected by two or more node devices.

That is, by using a ring type network for the node device arrangement, it is possible to secure high reliability and survivability as a communication network such as easy recovery at the time of failure. Furthermore, by limiting the communication network to the ring type, the route setting of the route is limited to clockwise or counterclockwise, and the route setting and resetting when opening the logical path or restoring the logical path at the time of failure, etc. The functions can be simplified, the hardware scale and algorithms for route editing can be reduced, and an economical communication network can be realized. In addition, by arranging a plurality of ring-type networks in a plane and connecting these ring-type networks with two or more node devices, high reliability, survivability, and economic efficiency can be achieved for large-scale communication networks such as nationwide. Can be expanded while securing

[0015] A third aspect of the present invention relates to an operation system for selecting a logical path, wherein each node device has control communication means for transmitting and receiving control signals to and from other node devices. At the time of path opening, the node device that has issued the logical path opening request sets the selection of the route to the destination node device sequentially while checking the idle state by directly accessing each node device without using an individual operation system. It is characterized by using a multi-path setting algorithm.

That is, when an independent operation system is not configured, when a logical path opening request is made, the node device that has issued the logical path opening request accesses each node device in the communication network individually and checks the idle state. Set the route. With such a configuration, it is possible to eliminate the individual operation system and the connection device that connects the operation system and each node device, which are conventionally required. Also, at the time of setting a route, the node device selects a route while grasping the logical path accommodation status of other node devices, so that the huge database management required for the conventionally required logical path accommodation design can be achieved. This eliminates the need for a route selection tool based on the vast database. In this way, an economical communication network can be realized by drastically changing the physical arrangement and algorithm for realizing the functions of the operation system and the like, particularly regarding the route setting.

A fourth aspect of the present invention relates to self-healing, in which the route setting of a first route of class A and a second route distributed in different routes is performed in a ring using the above-described route setting algorithm. In two node devices that are connected separately as a first route and a second route in a clockwise direction and a counterclockwise direction, respectively, and paths connected in a clockwise direction in two node devices that connect between rings are clockwise and counterclockwise, respectively. The paths connected around are connected in a counterclockwise direction so that the first path and the second path are connected without crossing each other. Further, when a failure occurs on a class B route, the route for avoiding the failure is reset by using the above-described route setting algorithm to recover the failure.

That is, instead of designing a path setting algorithm for establishing a logical path and a failure recovery algorithm at the time of self-healing independently as in the prior art, the path setting algorithm is utilized for both the establishment and the failure recovery. Thus, the load on the operation system can be reduced and an economical communication network can be realized.

That is, one aspect of the present invention includes a plurality of node devices and a physical transmission line connecting the plurality of node devices, and the node device and the node device via the physical transmission line. Is a communication network in which a logical path for transmitting an information signal is set between one start node device and one end node device. A feature of the present invention is that a plurality of logical paths having different transmission qualities are preset between the source node device and the destination node device, the information signal includes a service class identifier, and the source node device Has means for recognizing the identifier and means for selecting one of the plurality of logical paths according to the service class.

[0020] At least two service classes are provided, the first of which includes means for compensating for information loss occurring on the logical path, and the second is to allow information loss occurring on the logical path. Is desirable.

Alternatively, three service classes are provided, a class A of the service class is provided with a plurality of different routes for one route on the logical path, and a class B of the service class is a class B on the logical path. A means is provided for bypassing the fault location when a fault occurs in a part of the route for one route, and the class C of the service class is provided for the fault occurring in the route for one route on the logical path. A configuration having no alternative means may be adopted.

It is desirable that the plurality of routes are set in advance and autonomously by route setting means distributed in at least a part of the plurality of node devices.

Preferably, the route setting means includes a route setting algorithm for sequentially selecting and setting a route from a start point according to a service class from a plurality of routes connecting the start node device and the end node device.

A plurality of ring-type networks in which a large number of node devices are connected in a ring shape are formed, and the ring-type networks are connected to each other via two or more node devices. It is desirable to include means for setting two routes as duplicate routes in the clockwise direction and the counterclockwise direction in the type network.

Another aspect of the present invention is to transmit an information signal between one source node device and one destination node device in a network including a plurality of node devices and a physical transmission line connecting the node devices. This is a logical path route selection method for selecting a route of a logical path for transmission. A feature of the present invention is that a plurality of logical paths having different transmission qualities are set in advance between the start node device and the end node device, and a service class identifier mounted on an incoming information signal is used as an identifier. Therefore, a path for transmitting the information signal is to be selected from the plurality of logical paths.

It is desirable to provide three logical paths having different transmission qualities.

[0027] A ring network connecting a plurality of node devices in a ring by a physical transmission path is included, and the route on the logical path having high transmission quality passes through the ring network clockwise and counterclockwise, respectively. It is desirable that the settings are duplicated by two routes.

A plurality of the ring networks are formed,
It is desirable that the plurality of ring networks are mutually connected via two or more node devices.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction of an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a conceptual diagram of a communication network according to an embodiment of the present invention. FIG. 2 is a block diagram of the node device according to the embodiment of the present invention.

The present invention is a communication network comprising node devices A to C and a physical transmission line connecting the node devices A to C, and via the node devices A to C and the physical transmission lines. This is a communication network in which a logical path for transmitting an information signal is set between one start node device and one end node device among the node devices A to C.

Here, the feature of the present invention is that the multiplexed frame signal termination processing unit 13, the control communication unit 21, the logical path data collection unit 10, the logical path route setting unit 11, and the route connection processing unit 14 A plurality of logical paths having different transmission qualities are set in advance between the start node device and the end node device, the information signal includes a service class identifier ID, and the start node device recognizes the identifier. Service class identification unit 12 as
And a path selection processing unit 15 as means for selecting one from a plurality of logical paths according to the service class.

The service class includes a class A in which the first and second paths are set to transmit information and a class A in which information is normally transmitted through one path and a failure occurs in this path. It includes a class B in which information is transmitted by setting a route that bypasses a location, and a class C in which information is transmitted through one route and information loss due to failure is not compensated.

Next, the operation of the embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a diagram showing routing of a class A logical path. FIG. 4 is a diagram illustrating routing of a class B logical path. FIG. 5 is a diagram showing the routing of the class C logical path. FIG. 3 shows the node device A
2 shows the routing of a class A logical path, which is a logical path from the node A to the node device D. In the transmission node device A, after the transmission information is divided into two, the transmission direction is changed to the node device B,
Each of the routes 1-1 is counterclockwise via the node device C and clockwise via the node devices F and E.
1, transmitted as path 1-2, and on the receiving side, path 1
-1, a failure state is detected based on the communication state in the path 1-2, and information on a normal path side is selected. Regarding the method of realizing instantaneous interruption switching using this different path distribution,
Several methods have been considered so far, but the literature "Nobuyuki Kawase, Yoshiaki Yamabayashi, Masato Tomizawa, Shinji Matsuoka," Investigation of frame-free switching method in SDH network ", IEICE Transactions on Communications B-1 Vol.J78-B-1, No. 12,
pp. 764-772, 1995, the use of instantaneous interruption switching based on parity detection enables not only instantaneous interruption switching when a transmission path failure occurs but also transmission error rate during normal operation. It is possible to provide a high-quality logical path with an improved method, and this is considered to be the optimal method.

FIG. 4 shows the routing of a class B logical path. This logical path does not have a different path distribution configuration as in class A during normal operation. However, when a failure occurs, a route that bypasses the failed section is searched for, changed to another route, and the logical path is restored.

FIG. 5 shows a logical path of class C. This logical path does not not only have a different path distribution configuration as in class A, but also does not search for another path as in class B when a failure occurs. Therefore, the logical path is restored by restoring the failed equipment, for example, the physical transmission line, the transmission device, and the like. By providing logical paths having different self-healing levels in this way, a communication network can be constructed in which important information can be sent at any time and information giving priority to economic efficiency can be sent at extremely low prices.

As shown in FIGS. 3 to 5, transmission information from the node device A to the node device D is composed of only the three logical paths of the class A, class B, and class C. Thus, when the number of node devices is N, 3 × N (N−
1) The communication network can be managed with the number of logical paths of / 2 or less.

FIG. 6 is a diagram showing a form of node device arrangement in the communication network according to the embodiment of the present invention. In general, a ring network has an advantage that survivability is good and routing can be easily performed as compared with other topologies. The present invention describes the configuration of a communication network composed of a plurality of rings. This is because, when a large-scale communication network such as a nationwide one is configured based on rings, a plurality of ring types are required. FIG. 6 shows a basic node device arrangement according to the present invention, in which a ring α and a ring β are connected by two node devices, a node device B and a node device G. This not only enables a single link failure occurring in a communication network to recover from a failure link by bypassing the failure link, but also information (logical path) between any node devices other than the failure node device at the time of the node device failure. Is to be able to recover. Further, by using such a configuration, it is possible to configure a path that realizes class A between arbitrary node devices, that is, two routes that are distributed different routes without crossing node devices on the way. Further, since the number of adjacent node devices included in each node device is two or three, a route to be set in each node device is limited, and therefore, routing of a logical path at the time of opening or re-establishment of a logical path at the time of a failure. The setting can be performed with a simple algorithm. The link between the node device B and the node device G in FIG. 6 is shared by the ring α and the ring β.

FIG. 7 is a diagram showing a form of arrangement of node devices in the communication network according to the embodiment of the present invention, and shows an example in which the node devices are expanded and the number of links becomes three. In the present invention, it is important to connect the adjacent ring with the two-node device, and the ring α is the ring γ and the node devices G and H.
And the ring γ is connected to the ring β by the node devices F and G.

According to the path management method shown in the conventional example, as shown in FIG. 11, an individual operation system OpS which holds a free space of A to C in all the node devices in a database forms an optimum route. After searching,
A connection request has been made to each of the node devices A to C via the connection device 30.

On the other hand, according to the path management method of the embodiment of the present invention, as shown in FIG. 1, a main signal provided in each of the node devices A to C does not use an operation system which is another device different from the node devices A to C. The processing is performed using the processing unit 22, the path management unit 20, and the control communication unit 21 that transmits and receives control signals to and from other node devices. The main signal processing unit 22 is a function processing unit that manages a main signal system such as multiplexed frame signal termination processing, multiplexing and demultiplexing processing, logical path route setting and release, low-speed frame signal termination processing, inter-station and intra-station transmission. Path management unit 20
In the logical path data collection unit 10 shown in FIG. 2, the link capacity in the own node device is grasped (the path connectable capacity is grasped) and the connection state of the logical path is grasped. When a request for connection and release of a logical path is issued, the main signal processing unit 22 is instructed to set and release a path route. The service class identification unit 12 identifies the service class to which the information signal to be transmitted belongs, and instructs the main signal processing unit 22 to transfer the information signal to a corresponding logical path based on the identification result. give. The control communication unit 21 is used as a means for communicating with the path management unit 20 in another node device. In each node device,
Control information is extracted from the received signal by the main signal processing unit 22 and passed to the control communication unit 21. The control communication unit 21
Information such as a logical path from the control information is transferred to the path management unit 20.
To accept. When transmitting, they are received in the reverse order. Actual communication is performed by packet communication. Further, the packet information may be performed using a data communication channel (DCC) in the overhead provided in the multiplexed frame signal or a channel in another signal frame by wavelength multiplexing.

FIG. 8 is a diagram showing an example of a route setting algorithm in the communication network according to the embodiment of the present invention. The route setting algorithm according to the embodiment of the present invention does not use the operation system at the time of a logical path opening request, and the node device which has generated the logical path opening request individually accesses the route to the end node device to each node device to determine the idle state. Set sequentially while checking. Specifically, the exchange between the node devices is performed by exchanging control information between the path management units 20 shown in FIG. In FIG. 8, the node device A requested to open a path to the node device E passes through the node device C which is the shortest path to the ring β since the target node device E is not the own ring α but the ring β. Is selected, first, the possibility of setting a route to the node device B is confirmed (FIG. 8 (1)). In the node device B, after confirming the vacant state and performing temporary registration, the same confirmation is performed for the node device C (FIG. 8 (2)). The node device C selects the route via the node device D which is the shortest route to the node device E after confirming the vacant state and temporarily registering, and performs the same check on the node device D (FIG. 8 (3)). . In the node device D, after confirming the vacant state and temporarily registering, the same confirmation is performed for the node device E as the target node device (FIG. 8)
(4)). The node device E confirms that the own node device is the target node device and that the capacity from the requesting node device to the target node device is secured, and after the connection setting (FIG. 8 (5)), the above-described confirmation order And an instruction to set up / down link is transmitted in the reverse order (FIG. 8 (6)). Node device D
Then, after receiving the setting instruction from the node device E, the setting instruction is sent to the node device C (FIG. 8).
(7)). Hereinafter, similarly, the setting is completed in the node device A,
The route setting ends (FIGS. 8 (8) and 8 (9)).

FIG. 9 is a diagram showing an example of class A route setting in the communication network according to the embodiment of the present invention. The node device A requested to open the class A logical path requests the setting of two routes that are distributed differently using the clockwise route I and the counterclockwise route II. 9, the node device A transmits the target node device J as information to the node device F via the clockwise route (FIG. 9 (1)). In the node device F, after confirming the vacant state and temporarily registering, the node device E
Transmits the information from the node device A to the server (FIG. 9 (2)).
The node device E performs the same processing (FIG. 9 (3)). The node device D determines that the own node device is a bridge node device to the ring β as the clockwise route, selects the clockwise route also in the ring β, and transmits information to the node device J (FIG. 9 ( 4)). The node device J confirms that the node device itself is the target node device and that the capacity from the requesting node device to the target node device is secured, and after the connection is set (FIG. 9 (5)), And send out setting instructions in reverse order. On the other hand, the node device A also transmits the target node device J to the node device B as information along the counterclockwise route (FIG. 9 (6)). The node device B transmits the information from the node device A to the node device C after confirming the vacant state and temporarily registering (FIG. 9 (7)). The node device C determines that the own node device is a bridge node device to the ring β as the counterclockwise route, and also selects the counterclockwise route in the ring β to transfer information to the node device G.
(FIG. 9 (8)). The node device G transmits the information from the node device A to the node device H after confirming the vacant state and temporarily registering (FIG. 9 (9)). Similar processing is performed in the node devices H and I (FIG. 9 (10), FIG. 9 (1)
1)). The node device J confirms that the own node device is the target node device and that the capacity from the requesting node device to the target node device is secured, and after connection setting (FIG. 9 (12)), the above-described confirmation order And send out setting instructions in reverse order. With such a processing flow, the setting of a route having two routes that are distributed by different routes is completed.

FIG. 10 is a diagram showing an example of setting a class B route in the communication network according to the embodiment of the present invention. Since the logical path of class A is composed of two paths for different path distribution, a failure can be dealt with by selecting a normal path on the receiving side. The route of class C does nothing at the time of failure because it is a relief by facility restoration. On the other hand, a logical path of class B needs to search for another path and recover it when a failure occurs. In the present invention, restoration of the logical path of class B is performed using the route setting algorithm shown in FIG.
FIG. 10 shows a case where a failure occurs between the node devices B and C. In the node device A, a failure occurs in the ring α, and the route B from the own node device to the node device J
-1 is disconnected. Therefore, the node device A changes the route B-1 composed of the ring α-counterclockwise and the ring β-clockwise to the route B-2 composed of the ring α-clockwise and the ring β-clockwise. I do.
This change of the route is set while the node device A accesses the node devices F, E, and D, as described with reference to FIGS.

(Summary of Embodiment) In the communication network according to the embodiment of the present invention, a logical path to a target node device is set by setting a first path and a second path distributed in different paths, and a logical path is set when a failure occurs. Class A that switches path information without interruption
A logical path of class B, which searches for a new logical path route and recovers the logical path information when a failure occurs, and a class C logical path which recovers the logical path information by facility recovery without recovering the logical path information at the time of failure. By using only three logical paths, important information can be transmitted at any time, and information giving priority to economy can be transmitted extremely cheaply.

Further, by managing the logical paths between the node devices with only three large-capacity paths classified into classes, the number of paths to be managed in the communication network can be reduced, and the load on the operation system can be reduced.

Further, a plurality of node devices connected by logical paths are connected in a ring shape, a plurality of the ring networks are arranged in a plane, and the ring networks are connected by two or more node devices. In addition to ensuring high reliability and survivability as a communication network such as easy recovery in the event of a failure, using a ring-based communication network allows logical paths to be set clockwise and counterclockwise. Limited as
Path setting and resetting functions for opening a logical path or restoring a logical path in the event of a failure can be simplified, the hardware scale and algorithms for path editing can be reduced,
An economical communication network can be configured.

Each node device is provided with control communication means for transmitting and receiving control signals to and from other node devices, and when a logical path is opened, the node device which has issued a logical path opening request is sent to the end node device. By selecting the route to each node device sequentially without using an individual operation system and checking the free state by directly accessing each node device, individual operation systems and operation systems conventionally required The connection device that connects the node device can be deleted. Also, when setting up a logical path route, the node device selects the route while grasping the logical path accommodation status of other node devices, eliminating the need for huge database management conventionally required for logical path accommodation design. In addition, a route selection tool based on the huge database becomes unnecessary, and an economical communication network can be realized.

Further, the route setting of the first route constituting the logical path of the class A and the second route dispersed in the different route is performed clockwise and counterclockwise in the ring using the above-described route setting algorithm. In two node devices that are separately connected as a first route and a second route, and that connect between rings, a route connected clockwise is a clockwise route, and a route connected counterclockwise is a counterclockwise route. Around the first path and the second path without crossing each other, and when a failure occurs on a class B logical path, the failure is determined using the above-described path setting algorithm. By re-establishing the logical path by re-establishing the path that avoids the problem, the path setting algorithm for opening the logical path and the failure recovery algorithm at the time of self-healing are designed independently as in the past. Rather, by utilizing both for opening and for disaster recovery the routing algorithm, can reduce the load of the operating system, the economic can realize a communication network.

[0050]

As described above, according to the present invention,
A logical path having a plurality of transport functions can be set. The present invention can set a logical path capable of transmitting information without loss of information even when a failure occurs in highly reliable communication information, and perform economical information transmission for communication information that does not require reliability. Can be. Further, a ring network that can ensure high reliability and survivability can be easily configured.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of a communication network according to an embodiment of the present invention.

FIG. 2 is a block diagram of a node device according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating routing of a class A logical path;

FIG. 4 is a diagram illustrating routing of a logical path of class B;

FIG. 5 is a diagram illustrating routing of a class C logical path.

FIG. 6 is a diagram showing a form of arrangement of node devices in the communication network according to the embodiment of the present invention.

FIG. 7 is a diagram showing a form of node device arrangement in the communication network according to the embodiment of the present invention.

FIG. 8 is a diagram showing an example of a route setting algorithm in the communication network according to the embodiment of the present invention.

FIG. 9 is a diagram showing an example of setting a class A logical path route in the communication network according to the embodiment of the present invention.

FIG. 10 is a diagram showing an example of setting a class B logical path route in the communication network according to the embodiment of the present invention.

FIG. 11 is a conceptual diagram of a conventional communication network.

[Explanation of symbols]

1-1, 1-2 logical path 10 Logical path data collection unit 11 Logical path route setting unit 12 Service class identification part 13 Multiplexed frame signal termination processing unit 14 Route connection processing unit 15 Path selection processing unit 20 Path Management Department 21 Control communication unit 22 Main signal processing unit 30 connecting device AK node device B-1, B-2 path route ID identifier OpS operation system α, β ring I and II routes

Continuation of the front page (56) References JP-A-5-91103 (JP, A) JP-A-5-292111 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04L 12 / 56 H04L 12/437 H04L 29/14

Claims (7)

(57) [Claims] A plurality of node devices; and a physical transmission line connecting the plurality of node devices, wherein one of the node devices and a start node of the node devices via the physical transmission lines are provided. In a communication network in which a logical path for transmitting an information signal between the device and one end node device is set, a plurality of logical paths having different transmission qualities are set in advance between the start node device and the end node device, The information signal includes an identifier of a service class, the source node device recognizes the identifier,
Means for selecting one of the plurality of logical paths according to the service class , wherein three service classes are provided, and an upper class of the service class is one of the logical paths.
A plurality of different routes are provided for the route, and the service
The middle class of the class is assigned to one path on the logical path.
When a part of the route fails,
Means for bypassing the
Is generated for one route on the logical path.
A communication network characterized by having no alternative for a failed fault . 2. A plurality of node devices and a plurality of nodes
A physical transmission line connecting between the devices,
And the node device via the physical transmission path.
From one source node device to one end node device
Communication network with a logical path for transmitting information signals between
Transmission between the source node device and the destination node device in the network
Multiple logical paths with different qualities are set in advance and
The information signal includes an identifier of a service class, the source node device recognizes the identifier,
Of the plurality of logical paths according to the service class.
Means for selecting one, wherein the plurality of routes are
Distributed to at least a part of multiple node devices
Autonomous and autonomous by the route setting means provided
A communication network characterized by being set . 3. The apparatus according to claim 2, wherein said route setting means includes :
Service can be performed from multiple routes that connect to the destination node device.
Select and set the route in order from the starting point according to the scrus
The communication network according to claim 2, further comprising a routing algorithm . 4. A plurality of node devices are connected in a ring.
Multiple ring networks are configured, and
Network between two network devices via two or more node devices
And the path setting algorithm is linked to one link.
Clockwise and counterclockwise in a network
To set two routes as duplicate routes
4. The communication network of claim 3 , including a stage . 5. A connection between a plurality of node devices and the node devices.
In a network that includes
Information between the point node device and one end node device
A logical path for selecting a path of a logical path for transmitting a signal.
A path between the start node device and the end node device.
Pre-configure three logical paths of different quality
In advance, the service class installed in the incoming information signal
Path for transmitting the information signal according to the identifier of
Selecting from a plurality of logical paths
Logical path route selection method. 6. A connection between a plurality of node devices and the node devices.
In a network that includes
Information between the point node device and one end node device
A logical path for selecting a path of a logical path for transmitting a signal.
In the network path selection method, the network includes a plurality of node devices as physical transmission paths.
Including a ring type network connected in a ring shape , transmission between the start node device and the end node device
Set multiple logical paths of different quality in advance.
Of the service class mounted on the incoming information signal
A path for transmitting the information signal according to the identifier
Select from among the number of the logical path, the transmission Quality high logical
Each path on the logical path goes on the ring network
Two paths going clockwise and counterclockwise
Logical path setting characterized by being set in duplicate by
Road selection method. 7. A plurality of said ring networks are formed.
And connect the multiple ring networks to two or more nodes.
7. The logical path route selection method according to claim 6, wherein the logical path routes are interconnected via a device .