JP3235662B2 - Routing control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ATM device which supports an ATM (Asynchronous Transfer Mode) switching function without a dynamic path control function, and an ATM device such as ATM Forum PNNI.
The present invention relates to a route control method of a route control device including a route connection agent that supplies a function of 1.0.

[0002] The functions of this ATM Forum PNNI1.0 include:
(1) a routing function for dynamically identifying a path between two ATM end systems with which communication is desired;
(2) QOS (Quality) between the above ATM end systems
and a signaling function for setting up a connection that guarantees the service of service).

[0003]

2. Description of the Related Art In recent years, personal computers have been able to process various information such as data, voice, and images with a single personal computer. When the result of processing this information by a personal computer is read from another device, LAN / WAN connection on the same line is desired for physical and economic reasons. As a technique for solving this request, ATM (Asynchronous Trasfer) is used.
Communication by nsfer mode (asynchronous transfer mode) is in the spotlight. In an ATM network, SVC (Swit) is used to set routing information in header information in an ATM cell.
ched Virtual Connection: Virtual Connection Exchange / PVC (P
Before issuing user data, a virtual connection (hereinafter abbreviated as VC) must be set for both “ermanent VirtualConnection” and “end-to-end communication route” as a connection type. Normal V
From the setting of C to the release, the user data passes through the same route.

In such an ATM network, when a data error occurs due to deterioration of the line quality in the network, when the line is exchanged due to periodic maintenance, or when the line-compatible package of the ATM exchange is exchanged, the line passing through the line is exchanged. In some cases, an existing VC is disconnected and communication between end-to-end is interrupted. In this case, in order to secure a communication path between end users, it is necessary to select a line different from the line and switch the VC in the line to another route.

Japanese Patent Laid-Open Publication No. Hei 10-32575 discloses a method of switching to another route. In the switching request issuing side, network topology information from another device connected by ATM Forum P-NNI (ph.1) or the like is used. An acquisition function, a function of searching for a detour route for the VC from the network topology information, and a VPI to the detour route destination
= 0, VCI = 5, a connection request is issued to a detour route destination using a function of issuing a connection request message including detour information, and the detour route relay device has a signaling message exchange function and a connection function. Using the function of analyzing the request message and transferring the VC setting in the own device and the signaling message to the next device,
The connection switching message including the setting of the detour relay VC and the detour information to the next device is transferred, and the detour route terminating device analyzes the connection request message including the detour information and uses the function of switching the VC to be detoured to perform the VC switching. An ATM virtual connection switching method to be realized is described.

[0006]

However, the above A
Although the TM switching device has a PNNI function, a detour network setting function, and the like, it is difficult to determine a detour route, for example, when an ATM switching device without such a function is arranged. . In particular, if a communication failure occurs in an ATM device that supports only PVC (fixed connection), the operator needs to manually set a bypass PVC. If there are few PVCs, it is possible to recover communication in a relatively short time.
When a large number of are set, it takes time to grasp the entire contents, and communication restoration is delayed. Further, since the operator needs to set all the PVCs, setting such as the route is complicated.

The present invention relates to a simple ATM switching apparatus having only a connection setting function that enables a fixed connection in a limited manner, a route for setting a detour route and achieving a PNNI function even in the case of a route failure or the like. It is an object to facilitate setting of a network by using a control agent.

[0008]

According to the present invention, an ATM Forum PNNI1 is provided for an ATM device which supports only an ATM (Asynchronous Transfer Mode) exchange function PVC (fixed connection) without changing the ATM device. .0, to which the path connection agent is connected to the ATM device, wherein the path connection agent
A device status monitoring unit for monitoring the status of the M device;
A device status database that stores the status of the device, an agent database that stores a determination element that can delete a connection according to the status of the ATM device from the device status monitoring unit, and a PNNI (individually) that sets the connection of the ATM device. (Inter-network interface) An interwork processing unit, and a PNNI function unit that sets signaling with the PNNI interwork processing unit.

In the above route control system, the route connection agent issues a status request of the ATM device to the ATM device at predetermined time intervals by a device-agent communication protocol interface, and receives a response from the polling function. And stored in the device status database.

In the above route control system, if the ATM device does not respond even after exceeding a preset number of retries in the polling function,
It is characterized in that the apparatus is determined to be in a non-operating state or a failure.

The present invention also provides an ATM device which supports an ATM (Asynchronous Transfer Mode) switching function,
The ATM which applies the function of ATM Forum PNNI1.0 to the device
In a path control device comprising a path connection agent connected to a device, the path connection agent includes an agent function unit and a PNNI (individual network) for determining an optimal route to be used in a private network or ATM Internet to distinguish it from a public network. Interface) function section,
A communication function unit for communicating with the ATM device and a maintenance network, wherein the agent function unit
The PNN comprising a control management unit of the TM device, a device interface for transmitting and receiving data to and from the ATM device to be managed, a status monitoring unit of the ATM device, an agent database, and a device status database;
The I interface includes a PNNI signaling interface for communicating with the PNNI function unit and the PNN.
I function unit and a PNNI interwork processing unit that communicates with each other.
A driver for transmitting and receiving data to and from the TM device, a protocol interface for device-agent communication for performing data conversion with the driver and transmitting and receiving data to and from the device interface, and the maintenance network for a network for agent communication And a second driver for transmitting and receiving data to and from the second driver, and a protocol interface for agent communication connected to the second driver and exchanging with the PNNI interface.

Further, the present invention relates to an ATM (Asynchronous T
ransfer Mode (asynchronous transfer mode) Provides a configuration for applying the functions of the ATM Forum PNNI1.0 to ATM devices that support only PVC (Permanent Virtual Connection) such as a cross connector without making any changes to the ATM devices. . PNNI (Private Network-Network Interface)
By applying ace), dynamic routing can be performed even in an ATM device that supports only PVC.

In the present invention, referring to FIG. 1, the ATM network N1 is a network composed of ATM devices that support only PVC. ATM
Each ATM device (D1, D2, D
3 and D4) have routing agents (A
1, A2, A3, A4) are connected in the same manner as the connection method of the maintenance terminal. Each routing agent can communicate with each other through the maintenance network N2.

The routing control agent comprises: (1) a device management unit of the ATM device; (2) a function unit of the ATM Forum PNNI 1.0; and (3) a PN for associating the device status with the PNNI.
An NI interface, and (4) a communication function unit.
The routing control agent determines that each of the connected A
Monitor the status of the TM device and set / delete the PVC,
Further, according to the procedure of ATM Forum PNNI 1.0, it is possible to calculate the optimal route between each ATM device. In the event of a network failure, the path control agent sets a bypass PVC for the ATM device based on the obtained optimum path.
This enables dynamic path control in a network by an ATM device having no dynamic control function.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments according to the present invention will be described.
This will be described in detail with reference to the drawings.

(1) Description of Configuration First, FIG. 1 shows a conceptual diagram of a system according to the present embodiment.

In FIG. 1, the maintenance networks N2 and A
The maintenance network N2 is connected to the TM network N1, and the maintenance network N2 receives information from each of the route connection control agents A1 to A4.
Maintains an ATM network N1 to which each of the ATM devices D1 to D4, which is agented by the agent, is connected.

The ATM network N1 is a PVC
(Permanent Virtual Circuit: permanent connection).

The ATM devices (D1 to D4) may have an ATM management function by normal configuration management, fault management, performance management, device management, and setting management of addresses and the like.
In the present embodiment, the ATM device supports only a PVC in which a connection is fixedly set between terminals, and has an ATM switch having a switching function for directing an ATM cell transmitted like a so-called ATM exchange to target destination information. The device is an ATM-LAN control function, ATM cell transfer function, connection control (signaling), routing, traffic control (congestion control, resource management / allocation), network management function, IP over ATM, LAN Emulat
ATM that mainly processes the physical layer among functions such as ion
It is understood as an ATM switching device as a simple switcher having only a cell transfer function, and can be said to be an ATM switching device having no dynamic control function.

The route connection control agents A1 to A
4 has a function of executing a process based on autonomous judgment while supplementing a lacking function according to the intention of the ATM device.
According to an ATM forum in an independent network such as an AN, it provides further advanced functions. Therefore, in FIG. 1, although shown as a device independent of the ATM device, it can also be applied as an adapter of the ATM device, and an additional agent box is provided in the connector portion of the conventional ATM device, or inside the ATM device. It may be built in as a slot box, and can also be set to improve the functions of the ATM device and add missing functions.

Each of the ATM devices (D1, D2, D3, D4) included in the ATM network N1 has a routing control agent (A1, A2, A3, A4), respectively.
The connection is made using the same connection cable as the maintenance terminal. Each routing agent can communicate with each other through the maintenance network N2.

FIG. 2 shows a routing control agent (A
1, A2, A3, A4) and internal signal paths.

In FIG. 2, a routing control agent 1 exchanges information on the status of each link between an agent function unit 2 and each link used in a private network or ATM Internet to distinguish it from a public network.
P for recognizing the topology between switches in the network and resources in the network and determining the optimal route
It comprises an NNI (Private Network-Network Interface) function unit 3 and a communication function unit 4 for exchanging with an ATM device or a maintenance network. Routing agent 1
The agent function unit 2 includes a device management unit 5 and a PNNI
The device management unit 5 includes a PNNI interface 6 for exchanging with the function unit 3, and a device interface 11 for transmitting and receiving data from a communication device to be managed.
A device state monitoring unit 9, an agent database 7,
It comprises a device control unit 10 and a device status database 8.

The PNNI interface 6 has a P
It comprises an NNI signaling interface 14 and a PNNI interwork (interconnection) processing unit 12 having a processing unit 13 for performing an interconnection process. Also,
The communication function unit 4 includes a driver 16 for transmitting and receiving data to and from the ATM device of the communication device to be managed, and a driver 16.
A device-agent communication protocol interface 15 for converting data between the agent, a driver 18 for transmitting and receiving data to and from a maintenance network of the agent communication network, and an agent-to-agent communication protocol interface 17 connected to the driver 18. Consists of

[Device Status Monitoring Processing Unit] In this embodiment, the operation of the status monitoring processing unit 9 of the ATM device in the device management unit 5 of the agent function unit 2 shown in FIG. 2 will be mainly described. The agent function unit 2 makes it possible to apply the PNNI function to an ATM device having no PNNI function. Hereinafter, the state monitoring processing unit 9 of the agent function unit 2 will be described.

FIG. 3 shows a communication timing chart between the communication device of the ATM device to be managed and the routing control agent 1. FIG. 4 shows a flowchart of a specific operation. The routing control agent 1 sends data for causing the ATM device to report the status of the ATM device at predetermined time intervals. The routing control agent 1 periodically sends an ATM device status request at a polling interval time to check the status of the device. Acquisition and operation status of the device are determined.

In FIG. 3, first, in the initial state / device non-operation state, a request is sent from the agent function unit 2 of the routing control agent 1 for notification of the state of the ATM device to be managed (a). The communication device to be managed responds to the polling notification (b). Further, in the case of the device operating state, the routing control agent 1 sends a device status request at every polling interval time (p time) (c), and the communication device to be managed, which is an ATM device, receives the request. , The data corresponding to the request is detected, and the state of itself is responded as data (d).

If the ATM device to be managed is out of order, or a fault in the transmission line or a fault in the drive 16 of the route control agent 1, the route control agent 1
, A polling notification of the device status request is made, and if there is no response, the process is repeated again for the number of times of polling / retry.
If there is no response for the number of retries, the managed AT
The M device determines that the above-described ATM device has failed or is another failure, and notifies the maintenance network of the failure.

A description will be given based on the flowchart of the agent function unit 2 of the ATM device state monitoring unit shown in FIG. In advance, in this polling, a polling interval time is set as ptime, and the number of polling retries is set as pretry, and the current time is constantly monitored as current time (S0).

First, in the initial state, the ATM device to be managed is determined to be inactive (S1). A at regular intervals
In order to make a request for the status of the TM device, the current time is monitored, and a timer and a counter for the number of retries are initialized (S2), and then a device status request for the ATM device is made for polling (S3). The time elapsed since the request for the device state of the ATM device is calculated and compared with the polling interval time (S4). If it is within the polling interval, it is checked whether a response has been received (S5). If a response has been received, the ATM device is determined to be operating (S
6) Acquire the ATM device status from the response and update the device status database / PNNI database of the ATM device (S7). If no response is received within the polling interval in step 4, the device status request is repeated for the number of polling retries (S10, S9). If a response is not received within the number of polling retries in steps S10 and S9, it is determined that the ATM device is not operating (S11), and the device status database /
The PNNI database is updated (S7). If a response has not been received in step S5, the timer is shifted to step S4 according to the current time (S8), it is determined whether or not the current time is within the polling interval, and the flow shifts to step S7. From this database update process, the polling interval time and the number of polling retries are determined according to the characteristics of the ATM device to be managed.

[Device Control Processing Unit 10] Next, the device control processing unit 10 performs device control processing relating to registration / deletion of PVC by an ATM device that supports only PVC, with reference to FIG. PVC registration / deletion is performed by a request from the PNNI function unit.

The case where a new PVC is registered by the operator will be described with reference to FIG. When registering a new PVC, the operator inputs information required for PVC setting (S21). Further, the route information DTL (Designated Transit List) generated by the PNNI function unit 3 is acquired (S
22), SETU for appropriate PNNI signaling configuration
A P message is generated (S23) and transmitted to the PNNI function unit 3 via the processing unit 13 of the PNNI interworking unit 12 (S24). A new PVC is registered by the above steps.

Next, referring to FIG.
The case where C is deleted will be described. The operator selects the PVC to be deleted (S31). The information of the PVC to be deleted is acquired from the device status database, a RELEASE message for call disconnection in PNNI signaling is generated (S32), and transmitted to the PNNI function unit 3 through the processing unit 13 of the PNNI interwork processing unit 12 (S32). S33). Through these steps, the PVC is deleted.

Next, in FIG.
A case where a C registration request is received will be described. PNN
Upon receiving the PVC registration request from the I function unit 3 (S4
1), a PVC registration request is transmitted to the device interface 11 (S42). It is confirmed whether the PVC has been registered in the ATM device (S43). If the PVC registration is successful, the device status database 8 is updated via the device status interface 11 (S44), and the PVC setting ends (S45).
If PVC registration has failed in step S43, the PVC registration request is repeated for the number of retries (S46). If the number of retries has been exceeded, abnormality processing is performed (S47), and the device status database 8 is updated via the device status interface 11 (S45).

Next, referring to FIG.
The case where a deletion request is received will be described. PNNI
When a PVC deletion request is received from the functional unit 3 (S51),
A PVC deletion request is transmitted to the device interface 11 (S52). If the PVC deletion is successful (S53), the device status database is updated (S54). If the PVC deletion has failed in step S53, the PVC deletion request is repeated for the number of retries (S57, S53). If the number of retries has been exceeded (S57), abnormal processing is performed (S5).
8) The PNNI function unit 3 ends the PVC deletion request processing (S59). Next, a failure occurs in the relay node,
In order to confirm whether the PVC has been deleted, the deleted P
It is checked whether the VC calling side node has failed or is itself (S55). If not, the process ends (S
59) If it is, check whether the deletion of the PVC is due to a failure (S56). If the PVC is not deleted due to the failure, the process is terminated. If the cause is the PVC deletion, the route information DTL (Des
(S60), and obtains the appropriate P
A SETUP message for setting NNI signaling is generated (S61) and transmitted to the PNNI function unit 3 via the processing unit 13 of the PNNI interworking unit 12 (S62), and the PV
The update registration request processing for C is terminated (S59).

Referring to FIG. 9, a description will be given of the processing when a port failure occurs or when the apparatus is in the non-operation state. First, the device status is acquired from the device status database 8 (S71), and it is found that a port failure has occurred or the device has become inactive. In the case of a port failure (S72), a PN is assigned to the PVC associated with the port.
An NI signaling release message is generated (S7
3), and transmits it to the PNNI interworking unit 13 (S7)
4). In addition, when the device is in a non-operation state, all PVCs are
A PNNI signaling release message is generated (S73) and transmitted to the PNNI interworking unit 13.

[PNNI Interwork Process 12] PN
The NI interworking process 12 includes a PNNI function unit 3
NNI signaling interface 14, device-agent protocol interface 15, device control unit 5
The relay process of the PNNI message is performed between.

This will be described with reference to FIG. From the device-agent protocol interface 15 to the driver 16
When a PNNI message is received via
1), the route connection agent refers to the device status database 8 to check whether or not the ATM device to be managed is operating (S82), and if not, discards the PNNI message (S85). Further, if the port transmitting and receiving the message is in the failure state (S83) in the case of the operation state in step S82, the PNNI message is discarded (S85). Only when the ATM device is operating and the input / output port for transmission / reception is normal
The NNI message is relayed (S84). If the input or output port for this transmission / reception is not normal, the PNNI
The message is discarded (S85).

[PNNI Signaling Interface 14] The PNNI signaling interface 14
The device status database is updated by associating the PNNI signaling message with PVC registration / deletion. Here, PNNI signaling is an SVC (Switched Virtual CV) that dynamically sets a connection only during communication.
This is a protocol to set / release onnection.

The updating of the apparatus status database will be described with reference to FIG. Route connection agent is PN
Upon receiving the NI signaling message (S91),
The data is transmitted to the PNNI function unit 3 (S92). The PNNI function unit 3 selects an appropriate connection process according to the PNNI procedure (S93). If the connection is to be registered, a PVC registration request is issued.
A VC deletion request is transmitted to the device control unit (S94). Thereafter, the PNNI function unit 3 transmits a PNNI signaling message to the next node if necessary (S93). Here, in step S93 of the processing in the PNNI function unit 3, the PNNI signaling message is transmitted to the PNNI function unit 3 (S92), and the PNNI signaling message is analyzed (S95), and the data in the device state database 8 is referred to. And GCAC (Generic
A path that satisfies the quality of service (QOS) requested from Call Admission Control is selected (S
96), connection processing is performed (S97), and PVC registration /
A deletion request is transmitted to the device control unit (S94), a message is transmitted to the next node (corresponding to an agent) (S98), and the process ends.

[Device Interface 11] The device interface 11 performs a PVC registration request process, a deletion request process, and a device status request process from each functional unit by using an ATM.
The maintenance and management terminal MAT (Maintenance and
Administration Terminal) Converted according to the interface.

The case where the request processing of the device interface 11 is received will be described with reference to FIG. When the MAT interface of the ATM device is a command character string, each request process is received (S101), converted into an appropriate command character string (S102), and transmitted via the device-agent communication protocol interface 15 and the drive 16, AT
The data is transmitted to the M device (S103).

The reception processing from the ATM device will be described with reference to FIG. A character string is received from the ATM device via the device-agent communication protocol interface 15 (S111), the character string is analyzed and stored in an appropriate variable (S112), and the process is returned to each request process (S103).

[Agent Database 7] The agent database 7 is a database storing information for defining the movement of the agent and information for managing the communication address of the other agent for communicating with the other agent. It also stores data required for management of the ATM device.

[Device Status Database 8] The device status database 8 contains settings related to PNNI and device status (AT
M device port connection destination, port status, etc.), PVC
It stores information for managing information, and is inquired at the time of connection setting or at the time of various requests of an ATM device.
Data corresponding to the state change of the M device is written, and the corresponding data is read.

(2) Description of Operation Next, the operation of this embodiment will be described with reference to the drawings. First, it is assumed that a network shown in FIG. 14 is configured by four ATM devices that support only PVC. Each ATM device (D1, D2, D3, D4) has a routing control agent (A1, A2, A3, A
4) is connected. Each of the routing control agents (A1, A2, A3, A4) is connected to the maintenance network, and is notified of the state of the corresponding ATM device to be managed to the maintenance network. A1, A
(2, A3, A4).

FIG. 15 shows the logical connection between the routing agents. The connection destination of the ATM device to be managed is set in advance in each routing agent (in the case of the ATM device D1, $ D1: 00 port-D2:
01 port #, {D1: 01 port-D3: 00 port}). In accordance with the procedure shown in FIG. 4, each path control agent has finished recognizing the device managed by the operation of the state monitoring processing unit of the ATM apparatus, and the PNNI function unit 3 has completed the path calculation.

Here, the signal passes through the ATM devices D1 to D2,
A case where PVC is set up to D4 will be described (PVC {D1: 05 port-00 port} -PVC
{D2: 01 port-02 port} -PVC D4: 0
0 port-05 port II).

When a failure occurs between the ATM devices D1 and D2, the routing control agents A1 and A2 detect the failure according to the procedure shown in FIG. 4 and FIG. A release message is generated as PNNI signaling for the PVC associated with the failure, and each managed ATM device D
The PVCs 1 and D2 are deleted (PVC {D1: 05 port-00 port} and PVC {D2: 01 port-02 port}). Further, the routing control agent A2 has a PNNI
To send a PNNI signaling RELEASE message to the routing agent A3 by the functional unit, A
PVC of TM device D4 (PVC: $ D4: 00 port-
05 port｝) is also deleted.

When a failure has occurred, the PNNI function unit recalculates the route. In addition, the routing agent reissues the call because the PVC on the calling side has been deleted due to the failure. The PNNI signaling SETUP message transmitted by the routing agent A1 is the PNNI signaling SETUP message.
Based on the route information newly obtained by the functional unit, the AT
By being transferred from the M device D1 to D3, D2, D4, a bypass PVC from the ATM device D1 to D4 is set (FIG. 8), and the failure processing ends.

In the above-described embodiment, the number of ATM devices has been described as four. However, the number of ATM devices need not be limited to four. In the case of ATM devices having four or more devices, they are set hierarchically in the case of PVC setting. Separately into peer groups, PNNI routing may employ a hierarchical source routing scheme that combines the advantages of hop-by-hop routing and source routing.

Although the maintenance network N2 and the ATM network have been described as being separate from each other, the network may be the same using the same cable, and the network configuration may be a ring type. It may be dendritic.

[0053]

According to the present invention, according to the present invention, the agent
The device is monitored, and in the event of a failure, a route for which a bypass PVC should be set can be dynamically acquired by using the PNNI route calculation, so that a bypass PVC can be automatically set when a failure occurs.

Further, by applying the function of PNNI, the relay A can be set only by setting the calling side and the called side of the PVC.
Since the selection of the TM device is automatically performed, the setting of the network is facilitated.

[Brief description of the drawings]

FIG. 1 is a system block diagram showing an ATM device and a network thereof according to the present invention.

FIG. 2 is a configuration block diagram of a route connection agent according to the present invention.

FIG. 3 is an explanatory diagram of a communication routine between an ATM device and a path connection agent according to the present invention.

FIG. 4 is a flowchart of setting a device monitoring state of a route connection agent according to the present invention;

FIG. 5 is a flowchart of obtaining route information of a route connection agent according to the present invention.

FIG. 6 shows a PNNI of a route connection agent according to the present invention.
It is a flowchart of deletion.

FIG. 7 shows a PNNI of a path connection agent according to the present invention.
It is a flowchart of a setting.

FIG. 8 shows a PNNI of a route connection agent according to the present invention.
It is a flowchart of deletion and retry.

FIG. 9 is a flowchart at the time of a device failure of a route connection agent according to the present invention.

FIG. 10 shows an ATM of a path connection agent according to the present invention.
It is a flowchart of operation state detection of an apparatus.

FIG. 11 shows a PNN of a route connection agent according to the present invention.
It is a flowchart of I signaling.

FIG. 12 is a flowchart at the time of request processing of a path connection agent according to the present invention.

FIG. 13 is a flowchart when a character string is received between the ATM device and the route connection agent according to the present invention.

FIG. 14 is a system block diagram showing an ATM device and a network thereof according to the present invention.

FIG. 15 is an explanatory diagram of the operation of the route connection agent according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Route connection agent 2 Agent function part 3 PNNI function part 4 Communication function part 5 Device management part 6 PNNI interface part 7 Agent database 8 Device state database 9 Device state monitoring part 10 Device control part 11 Device interface 12 PNNI interwork processing part 13 Processing unit 14 PNNI signaling interface 15 Device-agent communication protocol interface 16 Driver 17 Agent communication protocol interface 18 Driver

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-11-205331 (JP, A) JP-A-10-303905 (JP, A) JP-A-9-36884 (JP, A) JP-A-63-1988 82145 (JP, A) JP 10-32575 (JP, A) JP 11-15804 (JP, A) JP 2000-49789 (JP, A) 1996 IEICE General Conference B-610 1997 Academic Communication Conference B-6-8 1998 IEICE General Conference B-6-37

Claims (12)

(57) [Claims] 1. An ATM Forum that supports only an ATM (Asynchronous Transfer Mode) exchange function that supports only a PVC (fixed connection) without changing the ATM device at all.
In a path control method in which a path connection agent is connected to the ATM device to which the function of PNNI1.0 is applied, the path connection agent stores a device state monitoring unit that monitors a state of the ATM device and a state of the ATM device. A device state database, and an agent database storing a determination element capable of deleting a connection according to a state of the ATM device from the device state monitoring unit,
A routing control method comprising: a PNNI (individual network interface) interwork processing unit for setting a connection of the ATM device; and a PNNI function unit for setting signaling with the PNNI interwork processing unit. 2. The routing control system according to claim 1, wherein said routing agent is connected to said ATM via a device-agent communication protocol interface.
A routing control method comprising: providing a polling function for generating a status request of the ATM device at a predetermined time interval and receiving a response to the ATM device; and storing the polling function in the device status database. 3. The routing control method according to claim 1, wherein when the ATM device does not respond even after exceeding a preset number of retries during the polling function, the ATM device does not operate. A path control method characterized by determining a state or a failure. 4. The routing method according to claim 1, wherein a polling interval time, a polling retry count, and a current time are set in advance in the polling function, and the ATM device is set for each polling interval time. And transmitting a device status request to the ATM device, and determining that the ATM device is not operating if there is no response from the ATM device even if the number of polling retries is exceeded. 5. The route control system according to claim 1, wherein the route connection agent determines whether the user
A routing control method for instructing a VC registration operation, acquiring routing information from the PNNI function unit, generating a setup message for the PNNI signaling, and transmitting the message to the PNNI interwork processing unit. 6. The route control system according to claim 1, wherein the route connection agent instructs a user to delete the PVC from a user, generates a release in the PNNI signaling, and outputs the release to the PNNI interworking processing unit. Transmitting the release message to the routing control method. 7. The routing control method according to claim 1, wherein when a PVC registration request is received from the PNNI function unit, the PVC setting request is transmitted to the ATM device, and the PVC setting is successful. For example, a routing control method characterized by updating data of the item in the device status database. 8. The routing control method according to claim 7, wherein if the response from the ATM device to the PVC setting request does not exceed the number of retries, the AT
A route control method, wherein it is determined that an abnormality has occurred in the M device, and the PVC setting is terminated. 9. The routing method according to claim 1, wherein when the PNNI function unit requests the ATM device to delete the PVC, the ATM device succeeds in deleting the PVC. The PNNI function unit updates the data of the item in the device status database, and the PNNI function unit according to the path information from the PNNI function unit.
A routing control method for generating a setup message for NNI signaling, transmitting the setup message to the PNNI interwork processing unit, and terminating the deletion of the PVC. 10. The routing control method according to claim 1, wherein when a failure occurs in the ATM device by the device state monitoring unit, the PNNI signaling is sent to the PVC associated with the failure portion. Wherein a release message is generated, transmitted to the PNNI interwork processing unit, and the release of the PVC is terminated. 11. The routing method according to claim 1, wherein, when a PNNI message is received from the ATM device, the routing agent sets the ATM connection.
A routing control method, wherein a response is made as to whether or not the apparatus is in an operating state, and if the apparatus is in an inactive state, the PNNI message is discarded. 12. The routing method according to claim 1, wherein the route connection agent, upon receiving a PNNI signaling message, sends the message to the PNNI function unit, and the PNNI function unit transmits the message to the PNNI function unit. A route control method characterized by analyzing the message with reference to a state database, selecting a route satisfying a predetermined quality of service, and executing a connection process of the ATM device by the route connection agent.