JP2001217830A - Communication network system and failure notifying method in communication network system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a communication network system which complements the management of network state information by a routing protocol and appropriately manages the network state information. SOLUTION: In this communication network system in which each of nodes 1 to 6 in the network stores the network state information, notifies all of the nodes 1 to 6 in the network of failure information by the routing protocol, changes the network state information of each of the nodes 1 to 6 and transfers a disconnected call message by reversely tracing the route through which a call setting message is transferred in the case of detecting a failure during call setting processing. Each of the nodes 1 to 6 transferring the disconnected call message changes the network state information of its own node, based on the failure information included in the disconnected call message.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication network system employing a source routing system in which each node has static connection information of a network topology fixed in advance, and a source node determines routing information to a destination. Regarding a failure notification method in a communication network system, in particular, by a routing protocol,
The present invention relates to a communication network system that manages network state information held by each node, and a failure notification method in the communication network system.

[0002]

2. Description of the Related Art As a conventional communication network system, for example, PNNI 1.0 (Priva
te Network-Network Interface Specification Version
1.0) and JP-A-10-285214. According to these communication network systems, when a failure is detected, a release message (call disconnection message) including information on the location of the failure is transmitted. The information of the failure point included in the release message is used only by the originating node or the equivalent of the originating node related to the call setting (the entrance node of the subnet when the subnet is configured), and the other nodes are not used.
Further, the information on the failure location is not reflected on the information on the network state of the topology data held by each node. Management and change of network state information held by each node has been performed only by a routing protocol.

[0003]

However, according to the above-mentioned prior art, the routing protocol has various imperfections such as delay, loss, and unreachability of the routing message. Since the management of the network state information is performed only by the protocol, there is a problem that the management of the network state information may not be performed properly. In addition, although the failure information is included in the call disconnect message, the failure information is not reflected in the network status information, so that the failure information included in the call disconnect message is not fully utilized. There was also.

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and has a problem in a communication network system which complements management of network state information by a routing protocol and appropriately manages network state information, and a failure in the communication network system. The purpose is to obtain a notification method.

[0005]

Means for Solving the Problems To solve the above-mentioned problems,
In order to achieve the object, in a communication network system according to the present invention, in a communication network system in which a plurality of node devices are communicably connected, each of the node devices has a holding unit for holding network state information; Routing protocol communication means for notifying information of a failure to all node devices in the network by a routing protocol and changing information of a network state of each of the node devices, and information of the failure when a failure is detected during a call setup process. Call disconnection message generating means for generating a call disconnection message including: a call disconnection message transfer means for transferring the call disconnection message generated by the call disconnection message generation means by reversing the route along which the call setup message was transferred. The call disconnection message transfer means of the own device When forwarding messages, characterized by comprising a first information changing means for changing information in the network status of the own apparatus based on the information of the failure to be included in the call disconnect message.

According to the present invention, the holding means holds the information on the network status, and the routing protocol communication means notifies the failure information to all the node devices in the network by the routing protocol, and the network status of each node device. When the call disconnection message generating means detects a failure during the call setup processing, the call disconnection message generation means generates a call disconnection message including the information of the failure, and the call disconnection message generation means generates the call disconnection message generation means. The call disconnection message is transferred by reversing the route to which the call setup message was transferred, and the first information changing means comprises:
When the call disconnection message transfer unit of the own device transfers the call disconnection message, the information of the network status of the own device is changed based on the failure information included in the call disconnection message. This makes it possible to change the network status information of each node device by effectively using the fault information included in the call disconnection message.

[0007] In the communication network system according to the next invention, when a failure is detected in communication other than the signaling protocol, a message generating means for generating a message including information on the failure, and a message generated by the message generating means. Transferring the message to another node device, and, when the message transferring device of the own device transfers the message, changing the network status information of the own device based on the failure information included in the message. 2 information changing means.

According to the present invention, when the message generation means detects a failure in communication other than the signaling protocol, the message generation means generates a message including information on the failure, and the message transfer means converts the message generated by the message generation means into another message. And the second information change means changes the network status information of the own device based on the failure information included in the message when the message transfer means of the own device transfers the message. Thus, the failure notification can be performed by a method other than the signaling protocol (such as a data transfer protocol with or without call setting).

In the communication network system according to the next invention, when each of the node devices detects a failure in communication by the connectionless transfer protocol, a message generating means for generating a message including information on the failure; A message transfer unit for transferring the message generated by the message generation unit to another node device, and a network of the own device based on information on a failure included in the message when the message transfer unit of the own device transfers the message. And second information changing means for changing state information.

According to the present invention, when the message generation means detects a failure in communication by the connectionless transfer protocol, the message generation means generates a message including information of the failure, and the message transfer means transmits the message generated by the message generation means. When the message is transferred to another node device, and the message transfer unit of the own device transfers the message, the second information changing unit changes the information on the network state of the own device based on the failure information included in the message. As a result, the failure notification can be performed by the connectionless transfer protocol.

[0011] In a communication network system according to the next invention, the message generation means adds source routing information indicating a transfer route to the message.

According to the present invention, the message generating means adds the source routing information indicating the transfer route to the message, so that the message can be transferred by following the route of the transfer data in reverse.

[0013] In the communication network system according to the next invention, when each of the node devices changes the information of the network state by means other than the routing protocol, it does not perform flooding for synchronizing the information of the network state. Features.

According to the present invention, when each node device changes network state information by means other than the routing protocol, flooding for synchronizing the network state information is not performed, thereby reducing an increase in control traffic. be able to.

In the communication network system according to the next invention, the information on the network state includes information on a failure level corresponding to a transfer failure factor for each communication function unit or each communication protocol of the node device. It is characterized by the following.

According to the present invention, fault management can be appropriately performed by including information on the fault level corresponding to the cause of the transfer fault for each communication function unit of the node device in the information on the network state. .

[0017] In a communication network system according to the next invention, the source node device determines routing information to a destination based on the failure level information.

According to the present invention, the source node device determines the routing information to the destination based on the failure level information, thereby increasing the probability that the control message or data can be transferred.

In the failure notification method in the communication network system according to the next invention, failure information is notified to all node devices in the network by a routing protocol, and the network status information held in each node device is changed. A first information change step of performing a call disconnection message by reversing the route to which the call setup message was transferred when a failure is detected during the call setup processing; A second information change step of changing the network state information based on the failure information included in the call disconnection message in each of the forwarding node devices.

According to the present invention, in the first information change step, failure information is notified to all the node devices in the network by the routing protocol, the network state information held in each node device is changed, and the message is changed. If a failure is detected during the call setup process in the transfer process, the call disconnection message is forwarded by reversing the route to which the call setup message was forwarded, and the call disconnection message is forwarded in the second information change process. In each node device, the network status information is changed based on the fault information included in the call disconnection message, thereby effectively utilizing the fault information included in the call disconnection message to check the network status of each node device. Information can be changed.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a communication network system and a failure notification method in the communication network system according to the present invention will be described in detail with reference to the drawings. The present invention is not limited by the embodiment.

FIG. 1 is a configuration diagram showing a configuration of a communication network system according to an embodiment of the present invention.
This communication network system has a plurality of communication network devices (nodes) 1, 2, 3, 4, 5, and 6, and each of the nodes 1 to 6 has a line 11, 12, 13, 14, 15,.
They are communicably connected by 16, 17, and 18.
Communication is performed between the nodes 1 to 6 by a routing protocol, a signaling protocol, a data transfer protocol with or without a call setting other than the signaling protocol, or the like, or without any protocol.

FIG. 2 is a functional block diagram showing a configuration example of the node according to this embodiment shown in FIG. Each of the nodes 1 to 6 has the same configuration, and has a routing function unit 21 for executing a routing protocol for notifying information of a failure to all node devices, and a signaling function unit 23 for executing a call connection by the signaling protocol.
And a data transfer function unit 2 for transferring data by a data transfer protocol other than the signaling protocol (such as a connectionless protocol) or independently of the protocol.
4, a topology data storage unit 25 for storing topology data including information on network status, and a topology management unit 22 for managing the topology data stored in the topology data storage unit 25.

When a failure is detected, the routing function unit 21 generates a routing message including information on the failure and floods the routing message. Also, if a routing message containing failure information is received from another node,
It instructs the topology management unit 22 to change the topology data based on the failure information included in the received routing message, and floods the routing message.

When a failure is detected during the call setup processing, the signaling function unit 23 generates a call disconnection message including information on the failure, and reverses the generated call disconnection message by reversing the route to which the call setup message was transferred. Follow the transfer. Further, when a call disconnection message is received from another node, the topology control unit 22 instructs the topology management unit 22 to change the topology data based on the failure information included in the received call disconnection message, and Is transferred in the reverse order of the route from which the call setup message was transferred.

When a failure is detected, the data transfer function unit 24 generates a message including source routing information indicating the data transfer path and information on the failure, and transfers the message by following the reverse of the data transfer path. Also, when receiving this message from another node, it instructs the topology management unit 22 to change the topology data based on the failure information included in this message,
This message is transferred following the reverse of the data transfer path. The topology management unit 22 includes the routing function unit 2
1. The topology data stored in the topology data storage unit 25 is changed according to instructions from the signaling function unit 23 and the data transfer function unit 24.

Each of the nodes 1 to 6 is involved in components other than the routing function unit 21 even when the topology data of the own node (the topology data stored in the topology data storage unit 25 of the own node) changes. When the change is topology data, flooding is not performed.
The topology data includes static connection information of the network topology, network state information, and routing information. The information on the network state may include information on a failure level corresponding to a cause of a transfer failure for each communication function unit or each communication protocol.

The operation of this embodiment in the above configuration will be described. For example, from node 1 to node 6
When a call is made to the node 1, the node 1 selects one piece of normal route routing information from the routing information from the node 1 to the node 6 stored in the topology data storage unit 25 of the node 1 itself. Here, all nodes 1 to 6
Recognizes that all the nodes 1 to 6 and the lines 11 to 17 are normal, and the node 1 passes through the line 14, the node 4, the line 18, the node 5, the line 16, the node 3, and the line 13. It is assumed that the routing information of the route to be selected is selected.

Node 1 receives a call request from a terminal (not shown) connected to node 1 and attempts to transfer a call setup message to node 6 to which a destination terminal (not shown) is connected. At this time, line 1 connecting node 3 and node 6
Assuming that a failure occurs in which the call setup message cannot be transferred, the routing function unit 21 of each of the nodes 3 and 6 connected to the failed line 13 instantaneously recognizes the failure and outputs the failure information. Attempt to flood a routing message containing (failure information) to all nodes. However, it is assumed that the node 1 has already transmitted the call setup message.

FIG. 3 is a sequence diagram showing a flow of a flooding message according to this embodiment. The nodes 3 and 6 recognize a failure that has occurred between the nodes 3 and 6, and transmit a flooding message (a routing message including failure information) relating to the failure to all adjacent nodes (nodes 2, 5, 6 and nodes 3 and 5). Send to However, the routing message may not be transmitted between the nodes 3 and 6 depending on the failure state. This is because failures range from failures specific to call setup (such as inability to secure resources such as bandwidth) to physical line disconnections. In the former case, a routing message can be sent, but in the latter case, In such a case, the routing message cannot be transmitted.

The node receiving this routing message recognizes the line state (network state) and sets the topology data to the line state. That is, the topology data of the own node is changed based on the failure information included in the routing message. Further, the routing message is further flooded to nodes adjacent to the own node (excluding the node that has transmitted the routing message).

FIG. 3 shows a point in time when the flooding message is flooded only to the nodes adjacent to the nodes 3 and 6 (nodes 2, 5, 6 and nodes 3 and 5). In FIG. 3, the flooding message from the node 3 and the flooding message from the node 6 are vertically shifted for easy viewing, but they occur almost simultaneously. At this point, as shown in FIG. 4, the topology data of the nodes 2, 3, 5, and 6 have been set to the line state,
In the topology data of No. 4, the setting of the line status has not been completed. In other words, although the failure information is reflected in the topology data of the nodes 2, 3, 5, and 6,
The failure information is not reflected in the topology data of.

At this point, since the node 1 has not recognized the failure yet, the node 6
It recognizes that the route to is normal and has already sent a call setup message. FIG. 5 is a sequence diagram showing a flow of a call setting message according to the embodiment. The call setup message transmitted from the node 1 is transferred to the node 3 via the nodes 4 and 5, but cannot be transferred to the node 6 using the line 13, and a failure is detected.

The signaling function unit 23 of the node 3 cannot transfer the call setup message using the line 13, detects a failure, generates a call disconnection message for rejecting the call setup message, and generates a call setup message. Is returned to the source node 1 on a route opposite to the route that has passed. here,
Failure information (failure point information) indicating that transfer between the nodes 3 and 6 is not possible is set in the call disconnection message. The failure point information includes at least the nodes 3 and 6
The information includes information indicating that there is an obstacle and information indicating that a failure has occurred.

Each node that has received the call disconnection message including the failure point information sets a failure state in its own topology data. That is, the failure information is reflected on the topology data of each of the nodes 3, 5, 4, and 1 of the transfer route. FIG. 6 is an explanatory diagram showing a change in topology data due to the call setting message according to this embodiment, and shows a point in time when the call disconnection message is transferred to the node 4. The nodes 3, 5, and 4 recognize the failure of the line 13 by the call disconnection message and change the topology data of the own node.

For example, as shown in FIG. 4, when a routing message has not arrived at the nodes 1 and 4 due to various factors such as processing delay, operation order, loss, and unreachability, the routing message is sent to the nodes 1 and 4.
No change is made to the topology data of No. 4. However, as shown in FIG. 6, if the call disconnect message arrives at the node 4, the failure information is transmitted by the call disconnect message to the node 4.
Can be reflected in the topology data. That is, by changing the topology data of each node by the routing message and changing the topology data of each node also by the call disconnection message,
Even if the routing message has not arrived or has not arrived, the topology data can be changed if the call disconnection message has arrived.

Thus, for example, when there is a call request from a terminal connected to node 4 to a terminal connected to node 6, the first route (route having the highest priority) to node 6 is set. Route via line 13 (line 1
Even if the route is via node 8, line 5, node 16, node 3 and line 13, and so on, the route avoiding line 13 recognized as having a fault (route via line 18, node 5 and line 17) Etc.) can be selected. That is, quick call setting is possible. The node 1 can also perform appropriate communication.

Next, a description will be given of an operation in a case where the originating node performs duplex switching in a state where a failure has occurred in the network and forgets all the network state information stored before the switching. . If the flooding message of the routing protocol transmitted when a failure occurs does not reach all the nodes in the network due to loss or the like, the topology data of each node in the network does not match. To avoid such network-wide topology data discrepancies,
In this communication network system, a flooding message of a routing protocol is also transmitted periodically.

For example, it is assumed that, in a state where a failure has occurred in the line 13, the node 1 performs duplex switching, and thereafter, a periodic flooding message has not been transmitted yet. In this case, as shown in FIG. 7, the topology data of the nodes other than the node 1 includes the line 13
Information that a failure has occurred is reflected,
Information that a failure has occurred in the line 13 is not reflected in the topology data of the node 1. Here, when the first route of the node 1 to the node 6 is a route via the line 14, the node 4, the line 18, the node 5, the line 16, the node 3, and the line 13, the call setting message is An attempt is made to make a call to node 6 via the route.

However, in this case as well, a failure is detected when the call setup message transmitted from the calling node 1 is transferred from the node 3 to the node 6 using the line 13. In the node 3, failure point information indicating that transfer between the nodes 3 and 6 is impossible is set in a call disconnection message rejecting the call setup message, and the originating node is routed in a reverse route to the route through which the call setup message has passed. Send to 1. Each node receiving the call disconnect message including the failure point information,
Set failure status in topology data.

When the call disconnection message is transferred to the originating node 1, the topology data of the node 1 is also stored in the line 1
The status that a failure has occurred is reflected in Step 3. As a result, a route that does not pass through the line 13 can be selected in the next call setting from the calling node 1.

FIG. 8 is an explanatory diagram showing the structure of a flooding message of a routing protocol according to this embodiment. The flooding message of the routing protocol includes, for example, a message header indicating a message type and a message length, a generation node ID that is an ID (identifier) of a node that generated (first transmitted) the flooding message, a node and a link, and the like. PT which is information indicating which information is shown below
SE (PNNI Topology State Element) type and PTS
A PTSE identifier which is a number set for uniquely identifying the information indicated by the E type, and a PSE which is information for ensuring that the routing message is the latest.
It is composed of a TSE sequence number and the contents of PTSE, which is the content to be notified by a flooding message such as the link status. PTSE is The ATM Foru
It is a unit defined by PNNI of m.

For example, as shown in FIG. 9, between node 1 and node 2, in addition to line 11, another line 1
Assuming that there are nine, the node 1 has the lines 19, 11, 1
A, b, and c are set as numbers that uniquely identify 4. In the node 2, a, b, and c are set as numbers for uniquely identifying the lines 19, 11, and 15, and in the node 4, a and b are set as numbers for uniquely identifying the lines 14 and 15. . In this case, Example 1 or Example 2 shown in FIG. 10 can be considered as the flooding message of the routing protocol transmitted from the node 1. In Example 1, a line number unique within the node 1 is used as the PTSE identifier, and in Example 2, a line number unique within the network is used as the PTSE identifier.

FIG. 11 is an explanatory diagram showing information in the topology data stored in the topology data storage unit 25 of each node according to this embodiment. Information in the topology data includes, for example, a node ID that is a unique node ID in the network, a node state indicating the operation state of the node, and a PTSE sequence number (for node information) for checking the freshness of the node information. ) And a line ID which is a number for uniquely identifying the line within the node
, A network line ID which is a number for uniquely identifying a line in a network, a line state indicating a line state, and a PTSE for checking the freshness of line information.
And a sequence number (for line information). The line ID corresponds to a, b, and c shown in FIG. 9, and the network line ID corresponds to 11, 14, 15, and 19 shown in FIG.

Next, the operation of each node will be described. FIG. 12 is an explanatory diagram illustrating the operation according to the routing protocol in the node according to the present embodiment. When any of the nodes 1 to 6 receives the flooding message 30 of the routing protocol, first, the routing function unit 21 performs message processing. In this message processing, message analysis and format check are performed.

Next, the routing function unit 21 checks the freshness of the information included in the flooding message 30, and in this information, the number set to the node or the line and the position information (global) for globally identifying these. In the example of FIG. 8, a query is made by passing the generation node ID and the PTSE identifier) to the topology management unit 22 (3 in FIG. 12).
1). The topology management unit 22 that has received the inquiry from the routing function unit 21 collects predetermined information from the topology data stored in the topology data storage unit 25. The predetermined information is retrieved and collected from the routing function unit 21 using, as keys, numbers set for nodes and lines and position information for globally identifying these.

The flood message 30 has a sequence number (PTS in the example of FIG. 8) of the flood message 30 so that its freshness can be confirmed.
E sequence number). This sequence number may be any number as long as the information can be uniquely identified. For example, the sequence number may be updated every time a flooding message is generated, or a time when the flooding message is generated may be set. You may. Since the time in the node is always measured by the built-in battery, if you set the time when the flood message was generated and set it as the sequence number, the sequence number will return to the initial value when the node is restarted Failures can be prevented.

This sequence number is passed from the routing function unit 21 to the topology management unit 22 together with the numbers set for the nodes and lines and the position information for globally identifying these. The information of the topology data in the topology data storage unit 25 also includes a sequence number (in the example of FIG. 11, a PTSE sequence number (for node information) and a PTSE sequence number (for line information)). The topology management unit 22 manages information in the topology data (node ID, node state, line ID, network line ID, line state, and the like in the example of FIG. 11) based on the sequence number.

For example, flood message 30
Is the message format shown in Example 1 of FIG. 10, the topology management unit 22 searches the topology data using the generation node ID and the PTSE identifier (a unique line number within the node) as keys. When the topology data includes the information shown in FIG. 11, first, a node ID is found from the generated node ID. Then, a line ID is found from the node ID and the PTSE identifier,
The PTSE sequence number (for line information) corresponding to this line ID is found.

On the other hand, the flooding message 30
In the case of the message format shown in Example 2 of FIG. 10, the topology management unit 22 searches the topology data using the PTSE identifier (a unique line number in the network) as a key. In this case, the line ID is found from the PTSE identifier, and the PTS corresponding to the line ID is found.
The E sequence number (for line information) can be found. In this case as well, the generation node ID is first changed to the node ID.
May be found. The above-described search method changes depending on the configuration of the topology data, the ID assignment policy, and the like.

The topology management unit 22 compares the sequence number of the flooding message 30 from the routing function unit 21 with the sequence number of the topology data obtained by searching, and
It determines the freshness of the information included in the information 0 and notifies the routing function unit 21 of the determination result. For example, if the sequence number is to be incremented, the flooding message 30
Is “1” and the sequence number of the topology data obtained by the search is “0”, the flooding message 3
It is determined that the information included in 0 is the latest.

When the up-to-dateness of the information included in the flooding message 30 becomes clear (when it becomes clear that the information of the flooding message is newer than the information of the topology data), the routing function unit 21 stores the topology data storage unit. The topology management unit 22 is requested to set new information (information of the flooding message 30) in 25. At this time, the sequence number of the information of the topology data is updated.

The sequence number can be updated only for the own node or a line connected to the own node (a line viewed from the own node), and is not updated for a line not connected to another node or the own node. The initial setting of the sequence number is performed when the node starts up or when a line is generated (recognizing the line). The update of the sequence number is performed at the time of periodic notification of a change in the network state or a flood message. Topology management unit 22
Confirms that the sequence number has been updated, sets the latest information in the topology data and transmits a state change notification 32 to the routing function unit 21.

The routing function unit 21 that has received the status change notification 32 performs flooding on an adjacent node other than the node that has transmitted the flooding message 30. In the case of a periodic notification or when a failure is detected, a routing message is generated by itself, so that the generated routing message is flooded to all adjacent nodes.

FIG. 13 is an explanatory diagram showing the operation according to the signaling protocol in the node according to this embodiment. When any of the nodes 1 to 6 receives the call disconnect message 40 of the signaling protocol, first, the signaling function unit 23 performs message processing. In this message processing, message analysis and format check are performed. Next, the signaling function unit 23 makes an inquiry to the topology management unit 22 to set the failure point information included in the call disconnection message 40.

As in the case of the routing protocol,
The topology management unit 22 that has received the inquiry collects predetermined information from the topology data recorded in the topology data recording unit 25, and the signaling function unit 23 adds new failure information (included in the call disconnection message 40) to the topology data. It requests the topology management unit 22 to set (failure point information) (41 in FIG. 13). However, unlike the routing protocol, since the sequence number does not exist in the message of the signaling protocol, comparison and setting of the sequence numbers are not performed. In this case, since the sequence number is not updated, the topology management unit 22
Does not send a status change notification to the routing function unit 21,
The routing function unit 21 does not perform flooding.

The management method of such topology data can be paraphrased as follows. That is, the failure point information based on a message of a protocol other than the routing protocol (such as a signaling protocol) is only a transient one or a complement of the routing protocol. It is only the routing protocol that synchronizes the topology data of the entire network, and in this respect the functions are clearly divided.

Even when topology data is changed by a signaling protocol, flooding is performed, and if an attempt is made to synchronize the entire network, control traffic increases. In addition, coexistence with a control message of a routing protocol causes synchronization of the entire network. Fluctuations occur. As described above, when the topology data is changed by a protocol (such as a signaling protocol) other than the routing protocol, the flooding is not performed, so that the number of control messages for synchronizing the network is increased without increasing the topology data. Can be improved.

FIG. 14 is an explanatory diagram showing the operation according to the data transfer protocol in the node according to this embodiment. In each of the nodes 1 to 6, data transfer is performed not only when a communication path is secured by a signaling protocol but also by connectionless transfer such as UDP without call setup. Further, it is performed by a protocol based on call setting other than the signaling protocol. Even in such a case, a failure point notification (notification of failure information) is possible.

In the case of connectionless transfer, the data transfer function unit 24 of the source node adds routing information to the destination node to the connectionless transfer data. If a failure point is encountered during the transfer of connectionless transfer data, the data transfer function unit 2 of the node that detected the failure
4 generates a failure point notification message (a message corresponding to a call disconnection message of the signaling protocol) including the failure point information and the routing information, and transmits the message to the source node. The transmitted failure point notification message is transferred along the reverse of the transfer path of the connectionless transfer data according to the routing information.

Each node that transfers the failure point notification message sets the failure information in the topology data in the same manner as in the case of the above-described signaling protocol. In this case, the data transfer function unit 24 performs processing instead of the signaling function unit 23. When each node receives the failure point notification message 50, the data transfer function unit 24 requests the topology management unit 22 to perform processing to set the failure point information in the topology data (51 in FIG. 14). In the data transfer by a protocol based on a call setting other than the signaling protocol and the data transfer not by the protocol, the failure information is similarly reflected in the topology data.

The above-mentioned fault information can be set in more detail. For example, in addition to the information that the line 13 connecting the nodes 3 and 6 is a failure point,
It is also possible to set information such as a type of a failure (failure factor) such as a protocol failure or a failure due to congestion. The failures include failures in which all protocols and communication function units (routing function unit 21, signaling function unit 23, data transfer function unit 24) cannot be transferred, and failures due to factors depending on each protocol and communication function unit ( There is a failure that prevents transfer by some protocols or communication function units). A failure factor for each protocol or communication function unit and a failure level corresponding to these failure factors may be set in the topology data of each node.

FIG. 15 is a table showing a correspondence between a failure factor and a failure level for each protocol according to this embodiment. In this communication network system, a failure factor 61 depending on a protocol type 60 such as a routing protocol, a signaling protocol, or another data transfer protocol is associated with a failure level 62 that determines whether call setting or data transfer is possible. The fault level 62 may be any level, but here, it is assumed that the fault level is divided into three stages: a severe fault, a medium fault, and a light fault. A severe failure is a failure in which all protocols and communication functions cannot be transferred, and a medium failure is a failure in which transfer cannot be performed due to factors depending on each protocol and communication functions. Is a failure that cannot be transferred basically due to factors depending on each protocol and the communication function unit, but may be transferable depending on the situation.

For example, if the routing protocol detects a physical line failure and recognizes that transfer is impossible,
Since transfer is impossible in all other protocols, it is associated with a serious failure. In addition, a resource shortage caused by an overflow of a bandwidth allocated for data transfer in a call setup of a signaling protocol is a meaningless (communicable) failure for a protocol that does not allocate a bandwidth such as connectionless transfer, so that a medium failure occurs. Is associated with.

In the case of transfer failure due to temporary congestion due to control data or user data transfer, it is considered that temporary burst traffic has occurred, and it is expected that protocol messages can be transferred immediately. Is associated with. In this way, by setting the failure factors for each protocol or communication function unit and the failure level corresponding to these failure factors in the topology data, it is possible to centrally manage the failures, and to set the failure factors and failures set in the topology data. Using the level, control messages and data can be transferred as much as possible.

The routing information may be selected using the information on the failure level. FIG. 16 is a flowchart illustrating the flow of the routing information determination process according to the present embodiment. In the routing information determining process, when the routing information is requested from the data transfer protocol or the communication function unit, the topology management unit 22 searches the routing information of the topology data stored in the topology data storage unit 25 (S1).
This routing information is managed for each destination,
The search is performed in order from the first candidate.

Next, the topology management unit 22 determines whether or not the route of the retrieved routing information has a failure (S2). If there is no obstacle in the route of the searched routing information, the searched routing information is selected, the route is determined, and the process is completed. On the other hand, if there is a failure in the route of the retrieved routing information, the failure level of the failure is determined by referring to the failure level information in the topology data (S3). If the failure level of the failure is a severe failure, it is impossible to transfer by any protocol and communication function unit, so it is determined whether there is routing information of the next candidate (S4), and the routing information of the next candidate is determined. If there is, the process returns to step S1. On the other hand, if there is no routing information of the next candidate, transfer is not possible, that is, the fact that there is no corresponding route is notified to the protocol or communication function unit, and the process is terminated.

If it is determined in step S3 that the failure is a medium failure or a minor failure, transfer is possible depending on the protocol or communication function unit, and the cause of the failure for each protocol or communication function unit is specified (S5). . That is, a failure factor relating to the requesting protocol or the communication function unit is specified. Then, a failure level corresponding to the identified failure factor is determined (S6). If the result of the determination is a medium fault,
Since the transfer cannot be performed by the protocol or the communication function unit of the request source, it is determined whether there is the next candidate routing information (S8), and if there is the next candidate routing information, the process returns to step S1. On the other hand, if there is no routing information of the next candidate, transfer is not possible, that is, the fact that there is no corresponding route is notified to the protocol or communication function unit, and the process is terminated.

If it is determined in step S6 that the failure is minor, it is determined whether or not there is routing information for the next candidate to increase the probability of transferability (S7). If there is no next candidate, the routing information is selected, a route is determined, and the process ends. On the other hand, if there is the next candidate routing information, the process returns to step S1.
Later, if you can't find a good route,
The route is determined by selecting the routing information of the route of the minor failure, and the process is completed. If there are many route candidates or it takes a long time to search for route candidates, when a minor failure is detected in a part of the route candidates, the route is notified to the protocol or communication function unit. Is also good. Further, all failure factors depending on each protocol and the communication function unit may be associated with a serious failure.

As described above, according to this embodiment, the topology data of each node is changed not only by the flooding message by the routing protocol but also by the call disconnection message by the signaling protocol. Even when failure information cannot be reflected in topology data due to factors such as delay or loss, more accurate topology state can be recognized and prompt call setup can be performed based on the failure information included in the call disconnect message by the signaling protocol. .

Further, even if network status information is forgotten due to the duplex setting, more accurate topology state can be recognized by the fault information included in the call disconnection message by the signaling protocol, and prompt call setting can be performed. Becomes possible. That is, the fault information included in the call disconnection message according to the signaling protocol can be effectively used to complement the imperfections of the routing protocol, and appropriate communication can be performed.

Further, when topology data is changed by a protocol other than the routing protocol, flooding is not performed, thereby improving the integrity of topology data without increasing the number of control messages for synchronizing networks. Can be done. In addition, since fault information can be notified by a data transfer protocol with or without a call setting other than the signaling protocol, or without depending on the protocol, communication reliability is improved and versatility is improved. Abundant fault monitoring can be performed.

Further, since the failure level associated with the failure factor is set in the topology data, it is possible to centrally manage the failures, and to control the control messages and data using the failure factors and the failure levels set in the topology data. Can be transferred as much as possible. Further, since the failure level is used for searching routing information, control messages and data can be transferred with high probability.

[0074]

As described above, according to the present invention, the holding means holds the information of the network state, and the routing protocol communication means notifies the failure information to all the node devices in the network by the routing protocol. When the call disconnection message generating means detects a failure during the call setup processing, the call disconnection message generation means generates a call disconnection message including the failure information, and the call disconnection message transfer means The call disconnection message generated by the call disconnection message generating means is transferred by reversing the route to which the call setting message was transferred, and the first information changing means transmits the call disconnection message by its own device. Transfer the network status information of the own device based on the failure information included in the call disconnection message. Further to. This makes it possible to change the network status information of each node device by effectively using the fault information included in the call disconnection message. There is an effect that information can be appropriately managed.

According to the next invention, when the message generation means detects a failure in communication other than the signaling protocol, the message generation means generates a message including information on the failure, and the message transfer means transmits the message generated by the message generation means. When the message is transferred to another node device, and the message transfer unit of the own device transfers the message, the second information changing unit changes the information on the network state of the own device based on the failure information included in the message. Accordingly, the failure notification can be performed by using a protocol other than the signaling protocol (such as a data transfer protocol with or without a call setup). Therefore, the reliability of management of network state information can be improved by using a protocol other than the signaling protocol. Thus, there is an effect that the reliability of management of network state information which is rich in versatility can be improved.

According to the next invention, when the message generation means detects a failure in communication by the connectionless transfer protocol, the message generation means generates a message including information of the failure, and the message transfer means generates the message generated by the message generation means. Is transferred to another node device, and when the message transfer unit of the own device transfers the message, the second information change unit changes the information of the network status of the own device based on the failure information included in the message. . Accordingly, the failure notification can be performed by the connectionless transfer protocol, so that the reliability of management of the network state information can be enhanced by the connectionless transfer protocol, and the versatile management of the network state information can be performed. The effect is that the reliability can be improved.

According to the next invention, the message generation means adds the source routing information indicating the transfer path to the message including the failure information, and transfers the message by reversing the route of the transfer data. The effect is that it can be done.

According to the next invention, when each node device changes network state information by means other than the routing protocol, flooding for synchronizing network state information is not performed, thereby reducing an increase in control traffic. Therefore, there is an effect that appropriate communication can be performed.

According to the next invention, since the information on the network state includes the information on the failure level corresponding to the cause of the transfer failure for each communication function unit of the node device, it is possible to appropriately manage the failure. The effect is as follows.

According to the next invention, since the source node device determines the routing information to the destination based on the information of the failure level, the probability that the control message or data can be transferred can be increased. It works.

According to the next invention, in the first information change step, failure information is notified to all the node devices in the network by the routing protocol, and the network state information held in each node device is changed. If a failure is detected during the call setup process in the message transfer process, the call disconnection message is forwarded following the route to which the call setup message was forwarded, and the call disconnection message is forwarded in the second information change process. In each node device, the network status information is changed based on the fault information included in the call disconnection message, thereby effectively utilizing the fault information included in the call disconnection message. Information can be changed, complementing the management of network status information by the routing protocol, and It is possible to manage the information over click state properly, an effect that.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of a communication network system according to an embodiment of the present invention.

FIG. 2 is a functional block diagram illustrating a configuration example of a node according to the embodiment illustrated in FIG. 1;

FIG. 3 is a sequence diagram showing a flow of a flooding message according to the embodiment;

FIG. 4 is an explanatory diagram showing a change in topology data due to flooding according to the embodiment;

FIG. 5 is a sequence diagram showing a flow of a call setup message according to the embodiment.

FIG. 6 is an explanatory diagram showing a change in topology data due to a call setting message according to the embodiment.

FIG. 7 is an explanatory diagram illustrating an example of a state of topology data according to the embodiment;

FIG. 8 is an explanatory diagram showing a configuration of a flooding message of a routing protocol according to the embodiment.

FIG. 9 is an explanatory diagram showing another configuration of the communication network system according to the embodiment.

FIG. 10 is an explanatory diagram illustrating an example of a flooding message of a routing protocol according to the embodiment;

FIG. 11 is an explanatory diagram showing information in topology data according to the embodiment;

FIG. 12 is a diagram illustrating a node according to the embodiment;
FIG. 4 is an explanatory diagram illustrating an operation according to a routing protocol.

FIG. 13 is a diagram illustrating a node according to the embodiment;
FIG. 4 is an explanatory diagram illustrating an operation according to a signaling protocol.

FIG. 14 is a diagram illustrating a node according to the embodiment;
FIG. 4 is an explanatory diagram showing an operation according to a data transfer protocol.

FIG. 15 is an explanatory diagram showing a correspondence between a failure factor and a failure level for each protocol according to the embodiment.

FIG. 16 is a flowchart illustrating a flow of a routing information determining process according to the embodiment;

[Explanation of symbols]

1 to 6 nodes, 11 to 19 lines, 21 routing function unit, 22 topology management unit, 23 signaling function unit, 24 data transfer function unit, 25 topology data storage unit.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5K030 GA12 HA08 HB18 KA05 LB01 LB05 LB18 LD11 LE12 MB01 MC07 5K035 AA03 BB03 CC08 CC09 DD01 EE01 JJ01 MM03 MM06 MM09

Claims (8)

[Claims] 1. A communication network system in which a plurality of node devices are communicably connected to each other, wherein each of the node devices holds network state information, and all node devices in a network receive fault information by a routing protocol. Routing protocol communication means for notifying the node device and changing the network state information of each of the node devices; and a call disconnection message generating means for generating a call disconnection message including the failure information when a failure is detected during the call setup processing. A call disconnection message transfer unit for transferring the call disconnection message generated by the call disconnection message generation unit by reversing the route to which the call setup message was transferred; and If the disconnect message is forwarded, it is included in the call disconnect message Communication network system characterized by comprising a first information changing means for changing information in the network status of the own apparatus based on the information harm. 2. Each of the node devices, when detecting a failure in communication other than a signaling protocol, generates a message including failure information, and transmits the message generated by the message generation device to another node device. A message transfer unit that transfers the message to the second device, and when the message transfer unit of the own device transfers the message, changes the information of the network state of the own device based on information of the failure included in the message.
The communication network system according to claim 1, further comprising: an information changing unit. 3. When each node device detects a failure in communication using a connectionless transfer protocol, the node device generates a message including information on the failure, and transmits the message generated by the message generation unit to another node. A message transfer unit for transferring the message to the device; and a second device for changing information on a network state of the device based on information on a failure included in the message when the message transfer unit of the device transfers the message.
The communication network system according to claim 1, further comprising: an information changing unit. 4. The communication network system according to claim 2, wherein said message generating means adds source routing information indicating a transfer route to said message. 5. The apparatus according to claim 1, wherein each of the node devices does not perform flooding for synchronizing the information on the network state when the information on the network state is changed by means other than the routing protocol. The communication network system according to one. 6. The network status information includes a failure level information corresponding to a cause of a transfer failure for each communication function unit or each communication protocol of the node device. The communication network system according to any one of the above. 7. The communication network system according to claim 6, wherein the source node device determines routing information to a destination based on the information on the failure level. 8. A first information change step of notifying fault information to all node devices in a network by a routing protocol and changing network state information held in each node device, and a fault during a call setup process. Is detected, a message transfer step of transferring the call disconnection message by reversing the route to which the call setup message has been transferred, and in each of the node devices transferring the call disconnection message, the message is included in the call disconnection message. A second information change step of changing information on a network state based on information on a failure; and a failure notification method in a communication network system.