JP2002232480A - Network management system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a network management system where management traffic attended with network management is not produced. SOLUTION: A communication unit 1 being an object to be managed stores management information 7 to a non-use part 26 of a transmitted packet 6 and transmits the resulting packet 6 where the management information and communication data are intermingled. On the other hand, management units 4, 5 receive all packets delivered through a network and discriminate whether or not the management information and the communication data are intermingled in the received packets based on the flag set to the packets. The management units 4, 5 extract the management information from the received packets and store the management information in them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a network management system, and more particularly, to a system for performing management using management information.

[0002]

2. Description of the Related Art In a conventional network management system, communication between a communication device to be managed and a management device is performed by a network protocol (hereinafter, referred to as a management protocol) prepared exclusively for transmitting management information. This is performed using

For example, in a TCP / IP network, SNMP (Sim) is generally used as a management protocol.
ple Network Management Pr
photocol) is used. Management information exchanged by SNMP includes MIB (Management I).
It is constructed based on a database called an nformation base (management information base). MIB
Is composed of a set of an object ID of the management information and a value of the management information. Since the management device and the communication device have the same structure of the MIB, the management device can specify what kind of information the management information transmitted from the communication device is. Basic set of MIB (MIB-II
) Is RFC (Request for C)
Comments) 1213.

Further, M. T. Rose, translated by Takeshi Nishida, "Introduction to TCP / IP Network Management Aiming for Practical Management" (Prentice Hall Toppan)
A method of packetizing management information when transmitting management information from a communication target device to be managed to a management device is disclosed.

Here, a brief description will be given of a flow of packetizing management information when transmitting management information from a communication device to be managed to a management device. First, MI
The management information constructed based on B is encoded using SNMP and becomes an SNMP message.

FIG. 16 shows a UDP (User Datag).
FIG. 4 is a diagram illustrating a configuration of a UDP packet format of a “ram Protocol” datagram. The SNMP message is encoded using UDP to become a UDP packet.

FIG. 17 shows an IP (Internet Pr).
FIG. 4 is a diagram showing a configuration of an IP packet format of an (autocol) datagram. The UDP packet is encoded using the IP as a UDP message, and transmitted as an IP packet to the management device. Thus, in the TCP / IP network, the management information is
It is packetized and transmitted from the communication device to be managed to the management device.

[0008] The IP packet created by the above-described packetization is a packet used only for transmitting management information. Therefore, the IP packet will be referred to as a management packet. In addition, traffic generated by transmission and reception of management packets is referred to as management traffic. On the other hand, a packet storing only data exchanged between communication devices (hereinafter, referred to as communication data) is referred to as a communication packet, and traffic generated by transmitting / receiving the communication packet is referred to as communication traffic.

[0009]

A method of transmitting management information by a management packet, as described in "Introduction to TCP / IP Network Management and Aiming at Practical Management", is a communication device to be managed. As a result, an increase in the number of management packets results in an increase in the number of management packets transmitted in proportion thereto. That is, the management traffic increases. An increase in management traffic causes a reduction in communication traffic. As a result, there arises a problem that the data communication performance of the network is impaired.

Therefore, an object of the present invention is to provide a system capable of transmitting management information without using a management packet.

[0011]

Means for Solving the Problems and Effects of the Invention In order to achieve the above object, the present invention has the following features.

According to a first aspect of the present invention, when packet communication is performed between a plurality of communication devices interconnected via a network, one or more management devices connected to the network transmit from any communication device. A network management system for managing communication devices based on management information included in a received packet, wherein each communication device detects whether communication data to be transmitted to another communication device exists. Communication data presence / absence detection means, management information presence / absence detection means for detecting whether there is management information to be transmitted to the management device, and operation in response to detection results of the communication data presence / absence detection means and management information presence / absence detection means If only communication data to be transmitted exists, only the communication data is stored in the packet and transmitted, and the communication data to be transmitted and the management information exist. Transmission means for storing both communication data and management information in a packet and transmitting the data. Each management device includes a reception unit for receiving all packets transmitted from an arbitrary communication device, and a reception unit. Determining means for determining whether or not the received packet contains the management information; and, as a result of the determination by the determining means, extracting the management information from the received packet when the received packet contains the management information. Management information extracting means.

As described above, according to the first aspect, the communication device to be managed mixes the management information into the packet in which the communication data is stored, thereby transmitting the management packet storing only the management information. The management information can be sent to the management device without generating it. Therefore, it is possible to suppress an increase in traffic due to the generation of the management packet. As a result, normal traffic is not suppressed by the generation of management traffic, and the generation of management traffic does not impair the data communication performance of the network.

[0014] The second invention is an invention according to the first invention, in which a packet has a data storage unit for storing communication data as standard and a special use purpose is not determined. When only communication data to be transmitted exists, the transmission unit stores the communication data in the data storage unit of the packet and transmits the communication data, and the communication data to be transmitted and the management information exist. In this case, the communication data is stored in a data storage unit of the packet, and the management information is stored and transmitted in an unused portion of the packet.

[0015] According to the second aspect of the present invention, the communication device stores management information in an unused portion of the packet, thereby effectively utilizing the unused portion of the packet and transmitting the management information and the communication data. Can be transmitted in a single packet.

A third invention is according to the second invention, wherein the transmission means stores communication data of a packet when management information to be transmitted exists and a predetermined condition is satisfied. The management information is forcibly stored and transmitted in the section

According to the third aspect of the present invention, if predetermined conditions are determined in advance, it becomes possible to forcibly and promptly transmit management information to the management device when the conditions are satisfied. . Thereby, the management device can acquire the management information under various conditions, and can perform more flexible management.

A fourth invention is an invention according to the third invention, wherein the transmitting means has been in a state where the management information is not transmitted, but the management information has not been transmitted for a certain period of time, despite the existence of the management information to be transmitted. In this case, the management information is forcibly stored and transmitted in the communication data storage unit of the packet.

As described above, according to the fourth aspect, it is possible to forcibly store and transmit the management information in a packet when the unstable state in which the management information is not transmitted has elapsed for a predetermined time. Thus, more stable network management can be performed.

A fifth invention is an invention according to the third invention, wherein a priority transmission designation as to whether the management information should be transmitted with priority is predetermined in the management information, When the management information to be transmitted is the management information designated to be transmitted preferentially, the transmitting unit forcibly stores the management information in the communication data storage unit of the packet and transmits the packet regardless of the presence or absence of the communication data to be transmitted. It is characterized by the following.

As described above, according to the fifth aspect, priority management can be designated in advance for management information requiring urgent transmission, and only management information is designated for priority transmission. Is stored in a packet and transmitted to the management device. As a result, the management information can be transmitted under the uniform condition of priority transmission designation, and network management can be made more stable.

A sixth invention is an invention according to the second invention, wherein the transmitting means has a size such that the management information to be transmitted has a size that cannot be stored in an unused portion of the packet at a time. The management information is divided into a plurality of parts, and the divided management information is transmitted by using a plurality of continuous packets. The management information extracting means transmits one management information divided into a plurality of packets and stored. In the case where a packet is received, a part of the management information is extracted from each of a series of received packets and temporarily stored, and when it is determined that the end of the management information is included in the received packet, the information is stored. It is characterized in that the original management information is reconstructed on the basis of a series of existing information.

As described above, according to the sixth aspect, the communication device can divide even long management information and transmit the divided management information to the management device in order. The management information can be reconstructed into the original management information. Therefore, even with complicated management information having a large amount of information, it is possible to exchange between the communication device and the management device.

[0024]

FIG. 1 is a diagram showing a configuration of a network according to an embodiment of the present invention. In FIG. 1, a communication device 1, a communication device 2, a communication device 3, a management device 4, and a management device 5 construct a network connected in a bus type. The communication device 1, the communication device 2, the communication device 3, the management device 4, and the management device 5 can mutually transmit and receive the packet 6. All packets 6
An unused portion 26 is included.

In this embodiment, the management information exchanged between the communication device and the management device is an object ID.
And the value of the variable. The object ID indicates the type of management information, and is determined in advance. The value of the variable indicates the state of the management information, and is a value that fluctuates within a predetermined range.

The management device and the communication device to be managed are determined in advance to indicate what kind of management information the object ID represents and what kind of management information the variable value represents. And a common database (hereinafter, referred to as a management information database). The management device, based on the management information database,
The type of management information sent from the communication device or the state of the management information can be recognized.

The communication device to be managed has an application for monitoring the content to be managed by itself. The communication device can acquire management information by operating the application.

Here, in order to understand the embodiment of the present invention, the relationship between the communication device and the management device and the management information will be described more specifically. As a network, a LAN network connected in a bus type is assumed. It is assumed that a personal computer as a communication device and a server as a management device are connected to this network. It is also assumed that a printer that can be used by a personal computer as a communication device is connected to this network. Also, it is assumed that the personal computer as a communication device has an application that constantly monitors the connection status with the printer.

Under such an assumption, "connection status with a printer" can be considered as the type of management information. As an example, the user adds the object ID “123” to the type of management information “connection status with printer”.
4 "is set in advance. On the other hand, the connection status with the printer may be" normal connection "or" abnormal connection ". The user assigns “1” to this “connection successful” value,
“0” is made to correspond to the value of “connection abnormality” in advance. As described above, the user determines in advance the possible values of the variables representing the state of the management information.

An application that constantly monitors the connection status with the printer includes, as management information, a set of “connection status with printer” and “normal connection” or “connection status with printer” and “abnormal connection”. You will get one of the pairs. These pieces of management information include the object ID
And the value of the variable as (1234, 1) or (1233, 0). Hereinafter, in the case of management information, it refers to a set of this object ID and a variable.

An application that constantly monitors the status of connection with the printer records the acquired management information in a management information file in a personal computer as a communication device. Thereafter, the personal computer as the communication device stores the recorded management information in a packet and transmits the packet to the server as the management device. The management information file will be described later.

Thereafter, the server, which is the management device, extracts management information from the packet transmitted from the personal computer, which is the communication device, and accumulates the management information. The server, which is a management device, performs operations such as displaying management information on a display in response to a user request. At this time, the server, which is the management device, displays the contents of the management information in a format that can be recognized by the user based on the management information database. Based on this displayed information,
The user can detect the abnormality of the printer and take some action.

In the above specific example, the management information indicating the connection status of the printer has been described for easy understanding, but other management information indicating other management items such as charging information and fault information may also be included. Conceivable.

In the network management system of the present invention configured as described above, the following three packets are transmitted from the communication device.

The first transmission packet is a packet that does not include any management information in the packet, that is, a communication packet that includes only communication data (hereinafter, this packet type is referred to as a “communication packet type”). The second transmission packet is
The management information is stored in the unused portion 26 of the packet, and the packet is a packet in which communication data and management information are mixed (hereinafter, this packet type is referred to as “unused portion storage type”). The third transmission packet is a packet including only management information, that is, a management packet (hereinafter, this packet type is referred to as a “management packet type”).

FIG. 1 schematically shows transmission of an unused part storage type packet. The communication device 1 stores the management information 7 in the unused portion 26 of the packet 6, and transmits the packet 6 including the management information. This storage method will be described later.

Here, it is assumed that the object to be managed is the communication device 1 in the network. Further, since the network is a bus network, the management devices 4 and 5 can receive all packets flowing on the network. Therefore, the management devices 4 and 5 can receive the packet 6 transmitted from the communication device 1. It is also assumed that a management device ID is assigned to each management device on the network by a user.

FIG. 2 is a diagram showing a more specific configuration of the packet 6 used in the embodiment of FIG. The configuration of this packet is common to each of the above-mentioned communication packet type, unused part storage type, and management packet type transmission packets.

In FIG. 2, the packet 6 is composed of a header 2
1 and a payload section 22. The header section 21 includes a source address storage section 23 and a destination address storage section 24.
, A payload length storage unit 25, and an unused portion 26.

The source address storage unit 23 stores an address of a source device that transmits a packet. The destination address storage unit 24 stores the address of a device on the network that is the destination of the packet. The payload length storage unit 25 stores the size of the payload unit 22.

The unused portion 26 stores all "0" as an initial value. However, when the packet is transmitted as the unused portion storage type described above, the unused portion 26 stores the control code and the management information. The storage method will be described later.

The payload section 22 includes a data storage section 27. The data storage unit 27 stores communication data or management information. When a packet is transmitted as the above-described communication packet type or unused part storage type, the data storage unit 27 stores communication data. On the other hand, when a packet is transmitted as the above-described management packet type, the data storage unit 27 stores management information.

FIG. 3 is a diagram showing the configuration of the unused portion 26 shown in FIG. The unused portion 26 includes a control code portion 36
And a management information section 37. The control code unit 36 includes a management flag storage unit 31, a management device ID storage unit 32, an extension flag storage unit 33, and an end flag storage unit 34. The management information section 37 includes a management information storage section 35.

The management flag storage unit 31 stores a management flag. The management device ID storage unit 32 stores a management device ID. The extension flag storage unit 33 stores an extension flag. The end flag storage unit 34 stores an end flag. The management information storage unit 35 stores management information.

Hereinafter, the management flag stored in the management flag storage unit 31 is MF31, the management device ID stored in the management device ID storage unit 32 is MID32, and the extension flag stored in the extension flag storage unit 33 is EX33. The end flag stored in the end flag storage unit 34 is set to EN34.
And the management information stored in the management information storage unit 35
35.

The MF 31 indicates whether the packet contains management information. If the packet includes the management information, the MF 31 sets “1”. If the packet does not include the management information, the MF 31 sets “0”.

The MID 32 is the management device I of the management device that wants to receive the management information contained in the packet to be transmitted.
Represents D. When the MID 32 is “0”, the management information included in the packet to be transmitted indicates that all the management apparatuses can receive the management information, that is, indicates that the broadcast is specified.

EX 33 indicates whether the management information is stored in the packet data storage unit 27 or the management information storage unit 35. If the management information is stored in the data storage unit 27, EX is set to “1”. On the other hand, if the management information is stored in the management information storage unit 35, EX is set to “0”. I do.

EN 34 indicates whether or not the data stored in the management information storage 35 includes the end of the management information. If the data stored in the management information storage unit 35 includes the end of the management information, EN is set to “1”; otherwise, EN is set to “0”.

Here, it is assumed that the size of the management information in this embodiment is larger than the size of DAT35.

The DAT 35 is an area used when storing management information in unused part storage type packets. Basically, the DAT 35 stores all “0” as an initial value. Therefore, in the communication packet type packet and the management packet type packet, the DAT35
Becomes all “0”.

On the other hand, in the packet of the unused part storage type, the management information is stored in the DAT 35.
In the present embodiment, since the size of the management information is larger than the size of the DAT 35, the management information is
When the information is stored in T35, the management information is cut out by the size of DAT35 and stored. Therefore, a part of the management information that has been cut off remains in the communication device.

When a part of the management information that has been cut off and stored is stored in an unused part storage type packet, the part of the management information is not always larger than the size of the DAT 35. Therefore, if a part of the management information is
When the data is stored in the T35, if the size is smaller than the size of the DAT35, a part of the management information and the initial value “0... 0” are stored in the DAT35.

As described above, the management information stored in the management information storage unit 35 includes the object ID and the value of the variable. The object ID is a value indicating the type of the management information. For example, when “operation information”, “billing information”, and “failure information” are the types of management information, the user sets the object ID of the operation information to “1111” as an example.
, The object ID of the billing information can be set to “2222”, and the object ID of the failure information can be set to “3333”. The value of the variable is a value indicating the state of the management information. For example, when the type of the management information is “charging information”, the status of the management information is “charged amount”, and the value of the variable is “1000”. When the type of the management information is “fault information”, the status of the management information is “fault number”, and the value of the variable is “1234”.

As described above, the management information storage unit 35 stores the object ID of the management information and the value of the variable.

FIG. 4 is a block diagram showing a more specific configuration of communication device 1 shown in FIG. Although FIG. 4 shows the configuration of the communication device 1 as a representative, it should be pointed out in advance that the other communication devices 2 and 3 have the same configuration as the communication device 1. In FIG. 4, the communication device 1
Is a processing unit 41, a communication data input buffer 42, a management information file 43, a management information buffer 44, a transmission option table 45, a timer 46,
And a D storage unit 47.

The processing section 41 is a section for executing the operation of the communication device 1. The communication data input buffer 42 holds communication data input by the user to the communication device 1 until the processing unit 41 processes the communication data. The management information file 43 records management information, that is, object IDs and values of variables. The management information buffer 44 temporarily stores the management information in order to perform a division process of the management information to be transmitted.

FIG. 5 shows the management information file 4 in FIG.
FIG. 3 is a diagram showing the configuration of FIG. As shown in FIG. 5, the management information file 43 stores a table describing object IDs and values of variables. In this table, a plurality of pieces of management information waiting for transmission are recorded.
Each management information recorded in this table is sequentially extracted by the processing unit 41 and stored in the management information buffer 44.

FIG. 6 shows the management information buffer 4 in FIG.
FIG. 4 is a diagram showing the configuration of FIG. 6 shows, as an example, a state in which the management information (0123, 0002) recorded in the first line of the management information file 43 in FIG. 5 is extracted by the processing unit 41 and stored in the management information buffer 44. . That is, in the management information buffer 44,
A set of management information to be transmitted next is stored.

When the management information is stored in a management packet type packet, a set of management information existing in the management information buffer 44 is stored in the data storage unit 27 by the processing unit 41. Usually, since the size of the data storage unit 27 is larger than the size of the management information, the management information is stored in the data storage unit without being divided.

On the other hand, when the management information is stored in the unused part storage type packet, a set of management information existing in the management information buffer 44 is stored in the management information storage unit 35. However, if the size of the management information is larger than the size of the management information storage unit 35, the management information is stored in the management information storage unit 3.
Does not fit in 5. Therefore, when the size of the management information is larger than the size of the management information storage unit 35, the processing unit 41 cuts out a part of the management information and stores it in the management information storage unit 35. That is, in this case, the management information is divided and stored in the management information storage unit 35.

FIG. 7 shows the management information buffer 4 in FIG.
4 shows the remaining management information when a part of the management information is cut off. In FIG. 7, “*” schematically represents a cut-out portion. A part of the management information (***, * 00
2) is stored in the packet and transmitted when the processing unit 41 next stores the management information in the packet.

FIG. 8 is a diagram showing the configuration of the transmission option table 45 in FIG. In FIG. 8, the transmission option table 45 includes an object ID 61
, A management device ID 62, and a priority transmission designation 63. The object ID 61 is an ID for identifying management information. The management device ID 62 is specified for each object ID 61, and the object ID
Is a management device ID of a management device capable of receiving the management information according to the above. If all management devices can receive the management information related to the object ID, the management device ID is not specified. The priority transmission designation 63 is represented by ON and OFF, and is ON when the management information is transmitted irrespective of the presence or absence of communication data, and OFF otherwise.

The timer 46 shown in FIG. 4 has a counter for counting a clock (not shown). That is, the count value of the counter increases at regular intervals in synchronization with the clock. The count value of the counter is output as a timer value. The timer 46 has two operating states, ON and OFF. In the ON state, the counter is started to increase the timer value. In the OFF state, the counter is stopped and the timer value is set to 0. Further, the timer 46 holds a predetermined threshold value.

The management device ID storage unit 47 temporarily stores the management device ID specified in the transmission option table 45.

The processing section 41 of the communication device 1 sequentially retrieves the management information existing in the management information file 43 and temporarily stores it in the management information buffer 44. The processing unit 41 refers to the transmission option table, determines a management device to which the management information is to be transmitted, stores the management information in a packet, and transmits the packet. The operation of the processing unit 41 will be described later in detail.

FIG. 9 is a block diagram showing a more specific configuration of the management device 4 in FIG. In FIG. 9,
Although the configuration of the management device 4 is typically shown, it is pointed out in advance that the other management devices 5 have the same configuration as the management device 4. In FIG. 9, the management device 4 includes a processing unit 51
, A plurality of management information buffers 52, a management target list 53, a management information file 54, and a management device ID storage unit 55.

The processing section 51 is a section for executing the operation of the management device 4. The management information buffer 52 is used for temporarily storing the management information extracted from the packet received by the processing unit 51 and reconstructing the management information. The management information buffer 52 is created corresponding to the source address of the packet.

The management target list 53 is a table in which addresses of communication devices existing on the network to be managed by the management device 4 are stored. The management target list 53
Predetermined by the user. Management information file 5
4 records the management information reconstructed by the management information buffer 52. The management device ID storage unit 55 stores the management device ID assigned to the management device 4 by the user.

The processing section 51 of the management apparatus 4 determines whether or not the received packet is a packet containing management information to be managed by itself. When determining that the received packet is a packet including management information to be managed by itself, the processing unit 51 extracts the management information from the received packet and temporarily stores the management information in the management information buffer 52. After that, the processing unit 51 records the management information reconstructed in the management information buffer 52 in the management information file 54. The operation of the processing unit 51 will be described later in detail.

Hereinafter, the operation of the network management system according to this embodiment will be described. Here, the operation when the management device 4 manages the communication device 1 will be described as an example, but the same operation is performed when any management device manages any communication device.

FIG. 10 is a flowchart showing a packet transmission operation executed by the processing unit 41 in FIG.
Hereinafter, the packet transmission operation in the communication device 1 will be described in more detail with reference to FIG.

The processing section 41 executes the timer 46 as an initial operation.
Is turned off (step S101). In response, timer 46 stops the counter and returns the timer value to zero.

Next, the processing section 41 sets the management information file 4
3 to determine whether there is management information, and based on the result, determine whether there is management information to be transmitted (step S
102). Here, when there is no management information to be transmitted, the processing unit 41 checks whether or not communication information exists in the communication data input buffer 42, and determines whether or not there is communication data to be transmitted based on a result thereof ( Step S10
3).

If there is no communication data in the communication data input buffer 42, the processing section 41 returns to the operation of step S102. Conversely, when communication data is present in the communication data input buffer 42, the processing unit 41 generates a packet and stores the communication data in the packet data storage unit 27 (step S104). Further, the processing unit 41 sets the MF 31 relating to the unused area 26 of the packet to “0” (Step S105). Next, the processing unit 41 transmits the communication packet (step S106), and proceeds to step S106.
The operation returns to operation 102. The packet transmission here is the communication packet type packet transmission described above.

If the management information to be transmitted exists in the management information file 43 in step S102,
The processing unit 41 extracts the management information from the management information file 43 and stores the management information in the management information buffer 44 (Step S107).

Next, the processing section 41 refers to the transmission option table 45 and determines whether or not the management device ID is specified as the object ID of the management information (step S108). If the management device ID is specified,
The processing unit 41 stores the management device ID in the management device ID storage unit 47 (Step S109). If the management device ID has not been specified, the processing unit 41 stores “0” in the management device ID storage unit 47 (Step S110). This “0” means that all the management devices on the network are designated, and so-called broadcast is designated.

Next, the processing section 41 refers to the transmission option table 45 again and determines whether or not priority transmission is specified in the object ID of the management information (step S111). Here, the priority transmission means that the management information is stored in a management packet type packet regardless of the presence or absence of the communication data, and the management information is immediately transmitted to the management device. That is, it can be said that the management information for which the priority transmission is specified is management information having contents to be sent to the management device immediately.

If priority transmission is specified in the object ID of the management information, the processing section 41 performs a management packet creation process (step S112). The management packet creation process is a process of storing management information in the packet data storage unit 27 and creating a management packet. The management packet creation process (step S112) will be described later in detail. Next, the processing unit 41 transmits the created management packet (Step S113), and returns to the operation of Step S102. The packet transmission here is the above-described management packet type packet transmission.

This operation (steps S111 to S113)
Accordingly, for the management information for which priority transmission is specified, the processing unit 41 can store the management information in a packet as soon as possible and transmit the packet to the management device. Thus, it is effective to designate priority transmission for urgent management information.

On the other hand, in the determination in step S111,
If priority transmission is not specified in the object ID of the management information, the processing unit 41 turns on the timer 46,
The counting of the timer value is started (step 114).

Next, the processing section 41 determines whether or not the timer value has exceeded a threshold value (step S115). If the timer value does not exceed the threshold value, the processing unit 41 determines whether there is communication data to be transmitted in the communication data input buffer 42 (step S117). If there is no communication data to be transmitted, the processing section 41 returns to the operation of step S115.

This operation (steps S115 and S11)
7) indicates that transmission of management information is suspended until communication data to be transmitted is generated. However, suspending the transmission of management information for a long time is not preferable from the viewpoint of network stability. This is because the management device cannot receive any management information from the communication device and cannot know any abnormality or the like occurring in the communication device.

Therefore, when the communication data to be transmitted does not occur even after the lapse of a certain time, that is, when the timer value exceeds the threshold value (step S115), the processing unit 4
1 performs a management packet creation process of storing management information in a management packet type packet (step S112), and performs an operation of transmitting a packet storing only the management information to the management device (step S113). It should be noted that, when the timer value exceeds the threshold value, the processing unit 41 turns off the timer 46, returns the timer value to 0, and stops the counter when the timer value exceeds the threshold value (for a while). Step S116). The management packet creation processing will be described later in detail.

In this way, it is possible to avoid an unstable state in which the management information from the communication device is not transmitted to the management device for a long time.

On the other hand, in the aforementioned step S117,
When there is communication data to be transmitted, the processing unit 41
The timer 46 is turned off, the timer value is returned to 0, and the counter is stopped (step S119). After that, the processing unit 4
1 generates a communication packet having the size of the communication data as the payload length, creates the header section 21, and stores the communication data in the packet data storage section 27 (step S1).
20). Next, the processing unit 41 performs a management information storage process of storing management information in which a control code is added to the unused part 26 of the communication packet storing the communication data (step S1).
21). This management information storage processing corresponds to creation of an unused part storage type packet. The management information storage processing will be described later in detail.

Next, the processing section 41 transmits a packet storing communication data and management information (step S1).
22). By this operation, the management information can be stored in the unused portion of the packet and transmitted together with the communication data.

In the present embodiment, since the size of the management information is assumed to be larger than the size of the management information storage unit 35, the processing unit 41 stores the management information in the management information storage unit 35 at one time. Impossible. Therefore, when the management information is stored in the management information storage unit 35 and the packet is transmitted, it is necessary to divide the packet several times to store the management information and transmit the packet. In the management information buffer 44, there is a part of the management information that cannot be stored in the management information storage unit 35 and remains.

Therefore, in order to transmit a part of the management information left in the management information buffer 44, the processing unit 41 determines whether the management information remains in the management information buffer 44 (step S123). . If the management information buffer 44 is empty, the processing unit 41 returns to the operation in step S102. On the other hand, if a part of the management information remains in the management information buffer 44, the processing unit 41 proceeds to step S1.
Returning to the operation of 14, the operation of transmitting the management information left in the management information buffer 44 is performed (steps S114 to S122).
Or S114 to S113).

FIG. 11 is a flowchart showing the management packet creation process (step S112) in FIG. 10 in more detail. Hereinafter, the management packet creation process will be described with reference to FIG.

First, the processing unit 41 sets the management information buffer 4
A packet having the same payload length as the size of the management information stored in No. 4 is generated, and the header section 21 of the packet is created (step S131). Next, the processing unit 41
The MF 31 of the unused portion 26 is set to "1" (step S132). This means that the packet contains management information. Next, the processing unit 41 stores the value of the management device ID stored in the management device ID storage unit 47 into the MID 32
(Step S133).

Next, the processing section 41 sets the unused portion 26
Is set to "1" in EX33 (step S134).
Further, the processing unit 41 sets the EN 34 of the unused portion 26
Is set to "1" (step S135).

A set of these flags (MF, EX, EN)
= (1,1,1) means a management packet in which management information is stored in the payload portion of the packet. That is, it means that the packet is a management packet type packet.

Finally, the processing section 41 takes out the management information stored in the management information buffer 44 and stores the management information in the data storage section 27 of the packet (step S136).

FIG. 12 is a flowchart showing the management information storing process (step S121) in FIG. 10 in more detail. First, the processing unit 41 sets “1” to the MF 31 of the unused portion 26 of the communication packet (step S1).
41). Next, the processing unit 41 stores the management device I in the MID 32.
The value of the management device ID stored in the D storage unit 47 is set (Step S142). Further, the processing unit 41 sets “0” to EX 33 of the unused portion 26 of the communication packet.

Next, the processing section 41 sets the management information buffer 4
4 is cut out by the size of the management information storage unit 35 and stored in the management information storage unit 35 (step S144).

In this embodiment, the size of the management information is
It is assumed that the size is larger than the size of the management information storage unit 35. Therefore, the management information buffer 44 includes a part of the management information that has been cut off and left. If the operation of cutting the management information by the size of the management information storage unit 35 and storing the cut management information in the management information storage unit 35 is repeated several times, the size of the management information remaining in the management information buffer Is the management information storage unit 35
May be less than the size.

As described above, when a part of the management information stored in the management information storage unit 35 is smaller than the size of the management information storage unit 35, the processing unit 41 stores the management information corresponding to the size of the management information storage unit 35. I can't cut it out. In such a case, the processing unit 41 extracts all of the management information left in the management information buffer 44, and
The remaining management information is stored in the storage area. Therefore, at this time, the management information is stored in the first half of the management information storage unit 35, and the initial value “0” is stored in the second half.

Next, the processing section 41 sets the management information buffer 4
Then, it is determined whether or not a part of the management information remains in No. 4 (step 145). When the management information data remains in the management information buffer 44, the processing unit 41 sets EN34 to “0” (step S146). Conversely, if no management information data remains, the processing unit 41
Is set to "1" (step S147).

A set of these flags (MF, EX) =
(1, 0) indicates that the packet is an unused portion 2 of the packet.
6 is a communication packet in which management information is stored. In other words, this means that the packet is of the unused part storage type described above.

Here, in the above-mentioned three types of packets, it is confirmed what value each flag of the control code section 36 takes.

When a packet is transmitted as a communication packet containing no management information in the packet, that is, when the packet is transmitted as a packet of the above-mentioned communication packet type, a set of flags (MF, MID, EX, EN)
Is (MF, MID, EX, EN) = (0, 0, 0,
0) (steps S104 and S105).

On the other hand, when the management information is stored in the unused portion 26 of the packet and the packet in which the management information and the communication data are mixed is transmitted, that is, the packet is transmitted as the previously described unused portion storage type packet. In this case, the set of flags (MF, MID, EX, EN) is (MF, MID,
EX, EN) = (1, value of management device ID, 0, 0),
(1, value of management device ID, 0, 1), (1, 0, 0,
0) or (1, 0, 0, 1) (step S1).
41 to S147).

When a packet is transmitted as a management packet containing only management information, that is, when a packet is transmitted as a packet of the above-mentioned management packet type, the set of flags (MF, MID, EX, EN) is MF, M
ID, EX, EN) = (1, value of management device ID, 1,
1) or (1, 0, 1, 1) (step S1).
32 to S135).

FIG. 13 is a flowchart showing the management information receiving operation executed by the processing unit 51 in FIG.
Hereinafter, the packet receiving operation in the management device 4 will be described in more detail with reference to FIG.

First, the processing section 51 receives a packet (step S201). Here, since the management device exists on a network connected in a bus form, it can receive all packets flowing on the network.

Next, the processing unit 51 reads the value of the MF 31 relating to the unused portion 26 of the received packet, and
It is determined whether 1 is "1" (step S20).
2).

If the MF 31 is “1”, the received packet contains management information. on the other hand,
If the MF 31 is not “1”, that is, if the MF 31 is “0”, the received packet does not include the management information.

Therefore, when the MF 31 is “0”, the processing section 51 performs the packet receiving process again (step S 201). On the other hand, when the MF 31 is “1”, the processing unit 51 performs the operation of step S203a and thereafter, and determines whether the management information is to be extracted by itself.

At step S203a, the processing section 51
Reads the value of MID32 and determines whether or not MID32 is "0" (step 203a). If M
If the ID 32 is “0”, it indicates that the management information included in the received packet is management information to be extracted by all the management devices. That is, MID32
Is "0", it means that the broadcast is the designated management information. on the other hand,
If the MID 32 is not “0”, the value of the MID is the value of the management device ID that should receive the management information.

Therefore, when MID32 is "0",
The processing unit 51 performs an operation of extracting the management information from the received packet in step S205 and subsequent steps. on the other hand,
If the MID 32 is not “0”, the processing unit 51
It is determined whether the value of D32 is the same as the value of the management device ID storage unit 55 (step S203b).

The MID 32 value and the management device ID storage unit 55
Are the same, the processing unit 51 proceeds to step S2
In the case of 05 or lower, the operation of extracting the management information from the received packet is performed. On the other hand, the value of MID32 and the management device I
If the value of D55 is different, the processing unit 51 refers to the management target list 53 and determines whether or not the transmission source address 23 of the received packet is included in the management target list 53 (step S204).

When the source address 23 of the received packet is not included in the management target list 53, the management information of the received packet is not the management information of the communication device to be managed by the management device 4. Therefore, the processing unit 51
It returns to the operation of the packet receiving process (step S201).
On the other hand, when the source address 23 of the received packet is included in the management target list, the management information of the received packet is the management information of the communication device to be managed by the management device 4. Therefore, the processing unit 51 performs an operation of extracting the management information from the packet by the operation after step S205.

By the operation of step S204, the management device can forcibly acquire the management information of the communication device to be managed by itself. Therefore, when the communication devices on the network are grouped, the user can specify the management device that manages a certain group by defining the management target list 53 of the management device.

The operation of the processing section 51 in step S205 and thereafter will now be described. Step S205
By the following operation, the processing unit 51 extracts management information from the received packet, reconstructs the management information, and records the reconstructed management information in the management information file 54.

First, the processing unit 51 determines whether or not the management information buffer 52 corresponding to the source address 23 of the received packet exists in the management device 4 (Step S).
205).

If the management information buffer 52 corresponding to the source address 23 of the received packet does not exist in the management device 4, the processing unit 51 creates the management information buffer 52 corresponding to the source address 23 of the received packet. (Step S205), and the next operation (step S207).
I do. On the other hand, the source address 23 of the received packet
When the management information buffer 52 corresponding to the received packet already exists in the management device 4, the processing unit 51 performs the next operation (step S207) without creating the management information buffer 52 corresponding to the source address 23 of the received packet. )I do.

The management information buffer 52 in the above operation is used for reconstructing the management information.

In step S207, the processing section 51
EX 33 relating to the unused portion 26 of the received packet
Is read, and it is determined whether EX33 is "0".
When EX33 is not “0”, that is, EX33 is “1”
, The management information is stored in the data storage unit 27 of the received packet. Accordingly, the processing unit 51 extracts the management information stored in the data storage unit 27 of the received packet, and adds the extracted management information to the management information buffer 52 corresponding to the source address of the received packet, and Is reconstructed (step S20).
8).

On the other hand, when EX 33 is “0”, the management information is stored in the management information storage unit 35. Therefore, the processing unit 51 sets the unused portion 26 of the received packet.
The management information stored in the management information storage unit 35 of the received packet is extracted, and the extracted management information is added to the management information buffer 52 corresponding to the source address of the received packet to reconstruct the management information (step S209). ).

Next, the processing section 51 reads the value of EN 34 relating to the unused portion 26 of the received packet,
It is determined whether 4 is "0" (step S210).

When EN34 is "0", the received packet does not include the end of the management information. Therefore, the processing unit 51 returns to the operation of step S201, continues the packet receiving process (step S201), and reconstructs the management information divided and transmitted from the communication device.

On the other hand, when EN34 is not "0", that is, when EN34 is "1", the received packet includes the end of the management information. Therefore,
The management information buffer 52 storing the management information in the previous step S208 or S209 contains the end of the management information. That is, the reconstruction of the management information has been completed. Therefore, the processing unit 51 records the contents of the management information buffer 52 corresponding to the source address of the received packet in the management information file 54 (Step S211).

Next, the processing section 51 deletes the management information buffer 52 corresponding to the source address of the received packet (step S212). By this operation, when new management information is transmitted from the same communication device, the processing unit 51
Can create the management information buffer 52 again and start reconstructing new management information. Next, the processing unit 51 returns to the operation of step S201, and continues the packet receiving process.

Next, the operation will be described more specifically by giving various conditions to the network management system in this embodiment.

First, it is assumed that the communication device 1 to be managed, the communication device 2 to be managed, the management device 4 and the management device 5 exist on the network. Communication device 1
And the communication device 2 have the same structure. It is assumed that the management device 4 and the management device 5 have the same structure.

Here, the user sets “4” as the management device ID in the management device 4 and the management device I in the management device 5.
It is assumed that “5” is assigned as D. FIG.
Is the transmission option table 1 held by the communication device 1.
40. FIG. 15 is a transmission option table 150 of the communication device 2.

Further, it is assumed that the management target list of the management device 4 includes the address of the communication device 1 and the address of the communication device 2. That is, the management device 4 always acquires management information of the communication device 1 and the communication device 2. It is also assumed that the management target list of the management device 5 does not include the address of the communication device 1.

The unused portion 26 of the packet is assumed to be 2 octets. Further, it is assumed that the MF 31 has 1 bit, the MID 32 has 5 bits, the EX 33 has 1 bit, the EN 34 has 1 bit, and the DAT 35 has 8 bits.

The first operation example is based on the assumption that the object ID “1234” and the corresponding variable value “0001” exist in the management information file 43 of the communication device 1 as management information. This is the operation with the device 4. In the management information file 43, the object ID and the value of the variable are handled as one set, so that the management information will be represented as (1234,0001).

First, the processing section 41 of the communication device 1 determines whether or not management information to be transmitted exists in the management information file 43 (step S102). In this case, since there is management information to be transmitted, the processing unit 41 stores the management information (1234, 0001) of the management information file 43 in the management information buffer 44 (step S107).

Next, the processing section 41 of the communication device 1 determines whether or not the management device ID is specified in the object ID “1234” of the management information to be transmitted with reference to the transmission option table 140 (step S108). ). The processing unit 41 refers to the transmission option table 140 and
It is known that “4” is specified as the management device ID of the object ID “1234”. Therefore, the processing unit 4
1 stores the management device ID “4” in the management device ID storage unit 47 (Step S109).

Next, the processing unit 41 of the communication device 1 refers to the transmission option table 140 again and determines whether or not priority transmission is specified in the object ID “1234” of the management information to be transmitted (step S1). S111). Since priority transmission is not specified for the object ID “1234”, it is not necessary to transmit this management information immediately. Therefore, the processing unit 41 turns on the timer 55 (step S114), and waits for transmission of management information until communication data to be transmitted is obtained or the timer value exceeds a threshold value (steps S115 and S115). S117
Loop).

Here, it is assumed that the processing unit 41 of the communication device 1 has obtained communication data to be transmitted before the timer value exceeds the threshold value. In this case, the processing unit 41 turns off the timer 46 (step S119), generates a packet, and stores the communication data in the packet (step S12).
0).

Next, the processing section 41 sets each flag of the control code section 36 of the unused portion 26. Since the packet to be transmitted contains management information, the MF 31
It becomes "1" (step S141). Also, MID32
Becomes "4" of the management device ID (step S14).
2). Further, since the management information is stored in the management information storage unit 35, the EX 33 is set to “0” (step S14).
3).

Next, the processing unit 41 of the communication device 1 executes the management information (1234,000) stored in the management information buffer 44.
1) is cut out by 8 bits of the size of the DAT 35 and stored in the management information storage unit 35 (step S14).
4). That is, the processing unit 41 of the communication device 1
The first eight bits “1” in (4,0001) are cut out and stored in the management information storage unit 35. Therefore, the management information buffer has a part (234, 0001) of the management information remaining after being cut off.

Therefore, the processing section 41 determines that the management information buffer 44 is not empty (step S145),
N34 is set to "0" (step S146). Thereby, it is possible to indicate that there is a continuation in the management information stored in the packet.

Next, the processing section 41 stores the management information storage section 35
Then, a packet in which the management information is stored is transmitted (step S122). This is the transmission of the previously described unused part storage type packet.

Next, the receiving operation on the management device side will be described. The management device 4 receives the packet transmitted from the communication device 1 earlier (step S201). The processing unit 51 of the management device 4 knows that the MF 31 is “1” (Step S202). That is, the received packet includes the management information.

Next, the processing unit 51 of the management device 4
32 is found to be its own management device ID "4" (step S203b). That is, the received packet includes the management information to be managed by the management device 4.

Therefore, the processing section 51 of the management apparatus 4 performs processing for extracting management information from the received packet in the operation after step S205.

The processing unit 51 of the management device 4 reads the source address from the source address storage unit 23 of the received packet, and determines whether or not the management information buffer 52 corresponding to the source address exists ( Step S20
5). Here, since the head of the management information has been sent from the communication device 1 for the first time, the management information buffer 52 corresponding to the source address does not exist. Therefore, the processing unit 51 of the management device 4 newly creates the management information buffer 52 corresponding to the source address (Step S206).

Next, the processing unit 51 of the management device 4 reads the EX 33 of the received packet and determines whether EX 33 is “0” (step S 207). here,
Since the management information is stored in the management information storage unit 35,
EX33 is "0". Therefore, the processing unit 51 of the management device 4 takes out a part of the management information from the management information storage unit 35 of the received packet, stores it in the management information buffer 52 corresponding to the transmission source address, and starts reconstructing the management information. .

Thereafter, the processing unit 51 of the management device 4 reads the EN34 of the received packet and sets EN34 to "0".
Is determined (step S210). Here, since the management information stored in the packet is the head of the management information, the end of the management information is not included in the received packet. Therefore, EN34 is
It is "0". Therefore, the receiving unit 51 of the management device 4 performs the packet reception process (S201) again to receive the remaining management information.

On the other hand, in the communication device 1, a part (23) of the management information (1234, 001) is stored in the management information buffer 44.
4,0001) still remain (step S12).
3), the processing unit 41 of the communication device 1
The process of storing and transmitting the remaining management information in the packet is repeated until 4 becomes empty (steps S114 to S123).

The processing unit 51 of the management device 4 stores a part of the management information divided and transmitted to the management information buffer 5.
2 (step S209), and the management information is reconstructed.

[0147] If EN34 is "1" (step S210), the received packet includes the end of the management information. Therefore, the processing unit 51 of the management device 4 takes out the reconstructed management information from the management information buffer 52 and records it in the management information file 54 (Step S211).

Next, the processing unit 51 of the management device 4 deletes the management information buffer 52 corresponding to the source address of the received packet (Step S212).

According to the first operation, the processing unit of the communication device stores the management information in an unused portion of the packet storing the communication data, and transmits the packet in which the communication data and the management information are mixed. It becomes possible. Further, the processing unit of the communication device may divide management information that cannot be stored in an unused portion of a single packet, store the management information in a plurality of packets, and transmit the packet as a packet including a part of the management information. Becomes possible. Further, the processing unit of the communication device can specify a management device that receives the management information transmitted by itself. In addition, the processing unit of the communication device can extract a part of the management information from the packet including the part of the management information, reconstruct it as one piece of connected management information, and record it.

The second operation example is different from the first operation example in that
This is the operation of the system when the timer value in step S115 exceeds the threshold value. The operation of the processing unit 41 of the communication device 1 up to step S115 is the same as the operation of the processing unit 41 in the first operation example, and thus the description is omitted.

If the timer value exceeds the threshold value in step S115, the processing unit 41 of the communication device 1 turns off the timer (step S116) and sets the same size as the remaining management information existing in the management information buffer 44. A packet having the data storage unit 27 is generated (step S13).
1). It is not preferable that the state where the management information is not transmitted continues for a long time in consideration of the stability of the network. Therefore, when the timer value exceeds a certain threshold value, the processing unit 41 of the communication device 1 performs an operation for forcibly transmitting management information.

Thereafter, the processing section 41 of the communication device 4 sets the MF 31 of the unused portion 26 of the packet to "1" (step S132), indicating that the packet contains management information. Next, the processing unit 41 of the communication device 4
Management device ID value “4” stored in the D storage unit 47
Is set to the value of the MID 32 (step S133).

Next, the processing unit 41 of the communication device 1
3 is set to "1" (step S134), indicating that the data storage unit 27 of the packet contains management information. Next, the processing unit 41 of the communication device 1 sets EN34 to “1” (step S135), indicating that the packet includes the end of the management information.

Next, the processing section 41 of the communication device 1 stores all of the remaining management information in the management information buffer 44 in the packet data storage section 27 (step S136).
The packet is transmitted (step S113). This is the transmission of the management packet type packet described above.

The processing section 51 of the management device 4 receives the packet transmitted from the communication device 4 and extracts the management information.
This operation is the same as that of the first operation example up to step S207, and thus the description is omitted.

The processing section 51 of the management device 4 executes step S2
At 07, it is determined that EX33 of the received packet is "1". Therefore, the management information is stored in the data storage unit 27 of the packet.

Next, the processing unit 51 of the management device 4 takes out all the remaining management information from the data storage unit 27 of the received packet, and takes out the data taken out into the management information buffer 52 corresponding to the source address of the received packet. Is added, and the management information is reconstructed (step S208). Subsequent operations of the processing unit 51 of the management device 4 are the same as those of the first operation example, and thus description thereof is omitted (steps S210 to S210).
212).

According to the second operation, when the communication device to be managed has no communication data to be transmitted for a certain period of time, the processing unit 41 of the communication device stores the management information in the data storage unit 27. Thus, the management information can be forcibly transmitted as a management packet.

[0159] The third operation example is the operation of the management device 5 for the packet transmitted from the communication device 1 in the first operation example. In this case, the operation of the processing unit 51 in the management device 5 from step S201 to step S203a is the same as the operation performed by the processing unit 51 in the management device 4 in the first operation example, and a description thereof will be omitted.

The processing unit 51 of the management device 5 determines in step S2
At 03b, it is read from the unused portion 26 of the received packet that the value of the MID 32 is "4". This is different from the management device ID “5” of the management device 5 (Step S203b). That is, the management information included in the received packet is not the management information specified by the communication device to be received by the management device 5. Therefore, the processing unit 51 of the management device 5 performs the operation of step S204 next.

Since it is assumed that the communication device 1 is not included in the management target list 53 of the management device 5, the processing unit 51 ignores the received packet. Therefore, the processing unit 51 of the management device 5 does not acquire the management information included in the received packet.

By the third operation, the management device can select a communication device to be managed.

The fourth operation example is based on the assumption that the object ID “1234” and the corresponding variable “0001” exist in the management information file 43 of the communication device 2 as management information. This is the acquisition operation.

The operation of the processing unit 41 in the communication device 2 is as follows.
Since the operation is the same as that of the communication device 1 in the first operation example, the description is omitted. In this case, based on the transmission option table 150, the processing unit 41 of the communication device 2
32 is set to “5”. In the management device 4, step S
The operation up to the operation 203a is the same as the operation of the management device 4 in the first operation example, and thus the description is omitted.

The processing unit 51 of the management device 4 executes step S2
At 03b, it is read that the value of the MID 32 is "5". Since this is different from its own management device ID “4”, the processing unit 51 of the management device 4 proceeds to step S20
4 is performed.

Since the communication device 2 is set as a management target in the management target list 53 of the management device 4 in the above assumption, the processing unit 51 of the management device 4 extracts the management information included in the received packet. There is a need. Therefore,
The processing unit 51 of the management device 4 performs an operation of extracting management information from the received packet by the operation after step S205.

According to the fourth operation example, the management device can forcibly acquire the management information of the communication device to be managed by itself, regardless of the designation from the communication device side.

The fifth operation example is an operation when it is assumed that an object ID “5678” and a variable “9999” corresponding to the object ID exist in the management information file 43 of the communication device 1.

The operation of the processing section 41 of the communication device 1 is the same as that of the first operation example from step S101 to step S108, and the description is omitted. Processing unit 4 of communication device 1
1 knows that the management device ID is not specified in the object ID “5678” of the management information to be transmitted by referring to the transmission option table 140 (step S10).
8). Therefore, this management information is management information to be managed in all management devices.

Next, the processing section 41 stores “0” in the management apparatus ID storage section (step S110). Subsequent operations in the communication device 1 are the same as in the first operation example and the second operation example, and a description thereof will be omitted.

On the other hand, management device 4 and management device 5 receive the packet transmitted from communication device 1. At this time, in step S203a, the processing unit 51 of each management device stores the received packet from the management device ID storage unit 32
Since it is determined that the MID 32 is “0”, step S
From 205 onward, a process of extracting the management information of the received packet is performed. This processing is the same as in the first operation example, and will not be described.

By the fifth operation, the predetermined management information can be determined on the communication device side so that all the management devices can receive it.

The sixth operation example is based on the assumption that the object ID “0123” and the corresponding variable “8888” are present in the management information file 43 of the communication device 1. Operation.

The operation of the processing section 41 of the communication device 1 is the same as that of the first operation example up to step S111, and thus the description is omitted. In step S111, the processing unit 41 of the communication device 1 refers to the transmission option table 140 and transmits the object ID “012” of the management information to be transmitted.
3 ”indicates that priority transmission is specified. Therefore, the management information is management information to be transmitted to the management device immediately.

Therefore, the processing section 41 performs management packet creation processing (step S112) and transmits management information. The operation of the management packet creation process is the same as that of the second operation example, and the description is omitted.

According to the sixth operation, regarding the management information for which priority transmission is specified in advance, the communication device forcibly downloads the management information using the payload portion of the packet regardless of the existence of communication data. It is possible to send at once. Therefore, urgent management information is transmitted as soon as possible.

In the above embodiment, the managed object is the communication device 1 or the communication device 2, but the managed object may be the communication device 3 separately. In this case, the communication device 3
It is necessary to have the same structure as the communication device 1. In addition, by providing the management device with the function of the communication device, the management device can be a communication device to be managed.

In the above embodiment, when communication data and management information are mixed and stored in a packet, the storage location of the management information is set to an unused portion of the packet. May be provided in advance, and the processing unit may store the management information in the fixed area, and store the communication data and the management information in the packet in a mixed manner.

Further, the management information file 43 of the communication device
May be a storage unit such as a memory other than the file.

In the above embodiment, when priority transmission is specified in the management information or when the timer value exceeds the threshold value, the management information is stored in a management packet type packet and the packet is transmitted. However, an operation of storing management information in a management packet type packet when certain other conditions are satisfied may be added.

Note that a communication device having another network management system and a management device may coexist on the network in this embodiment. In this case, if the management device of the present invention knows in advance the initial value of the unused portion when the packet is initialized in another network management system, the management device in the network management system of the present invention will use the value of MF31 Can be determined to determine whether the packet includes management information required by itself or a packet not including management information.

Further, in this embodiment, a bus network is assumed as the network, but a ring network may be employed as the network. Also in this case, the user can specify the management device that receives the management information using the transmission option table. The communication device to be managed stores the management device ID to be received in the unused portion of the packet. The management device can extract the management information by determining whether or not its own management device ID is included in the unused portion of the received packet.

In a ring type network,
The user can determine the management target list in the management device in advance. Even in the above-described ring network, the management device, even if its own management device ID is not specified in the received packet, if the address of the communication device of the transmission source is included in the management target list of the management device, It is possible to forcibly acquire management information.

[Brief description of the drawings]

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

FIG. 2 is a diagram showing a more specific configuration of a packet 6 used in the embodiment of FIG.

FIG. 3 is a diagram showing a configuration of an unused portion 26 shown in FIG. 2;

FIG. 4 is a block diagram showing a more specific configuration of the communication device 1 shown in FIG.

FIG. 5 is a diagram showing a configuration of a management information file 43 in FIG.

FIG. 6 is a diagram showing a configuration of a management information buffer 44 in FIG.

FIG. 7 shows a management information buffer 44 in FIG.
It is a figure showing the remaining management information when a part of management information is cut.

8 is a diagram showing a configuration of a transmission option table 45 in FIG.

9 is a block diagram showing a more specific configuration of the management device 4 in FIG.

FIG. 10 is a flowchart showing a packet transmitting operation performed by a processing unit 41 in FIG. 4;

11 is a flowchart showing the management packet creation process in FIG. 10 in more detail.

12 is a flowchart showing the management information storage processing in FIG. 10 in more detail.

FIG. 13 is a flowchart showing a management information receiving operation executed by a processing unit 51 in FIG. 9;

FIG. 14 is a diagram showing a transmission option table held by the communication device 1 in an operation example.

FIG. 15 is a diagram illustrating a transmission option table held by the communication device 2 in an operation example.

FIG. 16 is a diagram showing a configuration of a UDP packet format of a UDP datagram.

FIG. 17 is a diagram showing a configuration of an IP packet format of an IP datagram.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 communication device 2 communication device 3 communication device 4 management device 5 management device 6 packet 7 management information 21 header portion 22 payload portion 23 source address storage portion 24 destination address storage portion 25 ... Payload length storage unit 26 ... Unused part 27 ... Data storage unit 31 ... Management flag storage unit 32 ... Management device ID storage unit 33 ... Extension flag storage unit 35 ... End flag storage unit 36 ... Control code unit 37 ... Management information unit 41 processing unit 42 communication data input buffer 43 management information file 44 management information buffer 45 transmission option table 46 timer 47 management device ID storage unit 51 processing unit 52 management information buffer 53 management target list 54 ... management information file 55 ... management device ID storage unit 140 ... transmission option table 150 ... transmission Deployment table

Claims (6)

[Claims] When performing packet communication between a plurality of communication apparatuses interconnected via a network,
A network management system in which one or a plurality of management devices connected to the network manage communication devices based on management information included in a packet transmitted from an arbitrary communication device, wherein each of the communication devices is Communication data presence / absence detection means for detecting whether communication data to be transmitted to another communication device exists; and management information presence / absence detection means for detecting whether management information to be transmitted to the management device exists Operates in response to the detection result of the communication data presence / absence detection means and the management information presence / absence detection means, and when only communication data to be transmitted exists, stores only the communication data in the packet and transmits the packet; Transmission means for storing both communication data and management information in a packet when there is communication data and management information to be transmitted, A management device, receiving means for receiving all packets transmitted from any communication device, determining means for determining whether or not the packet received by the receiving means includes management information; and A network management system comprising: a management information extracting unit that extracts management information from a received packet when the received packet includes management information as a result of the determination. 2. The packet includes, as a part thereof, a data storage unit for storing communication data in a standard manner and an unused part for which a special purpose of use is not determined. If only the communication data exists, the communication data is stored and transmitted in the data storage of the packet. If the communication data to be transmitted and the management information exist, the communication data is stored in the data storage of the packet. 2. The network management system according to claim 1, wherein the management information is stored in an unused portion of the packet and transmitted. 3. The transmitting means forcibly stores and transmits the management information in a communication data storage unit of a packet when management information to be transmitted exists and a predetermined condition is satisfied. 3. The network management system according to claim 2, wherein the network management system is characterized by: 4. The transmitting means forcibly stores the management information in a communication data storage unit of a packet when a state in which the management information is not transmitted has passed for a certain period of time, despite the presence of the management information to be transmitted. 4. The network management system according to claim 3, wherein the network management system stores and transmits the stored data. 5. A priority transmission designation as to whether or not the management information is to be transmitted with priority is predetermined in the management information, and the transmission means determines that the management information to be transmitted is the priority transmission designation. 4. The network according to claim 3, wherein when the management information is transmitted, the management information is forcibly stored in the communication data storage unit of the packet and transmitted regardless of the presence or absence of communication data to be transmitted. Management system. 6. When the management information to be transmitted has a size that cannot be stored in an unused portion of the packet at a time, the transmitting unit divides the management information into a plurality of portions, and The management information is transmitted using a plurality of continuous packets, and the management information extracting means, when one management information is divided and stored in a plurality of packets and transmitted, receives management information from a series of received packets. Of the management information is temporarily stored, and when it is determined that the received packet includes the end of the management information, the original management information is determined based on the stored series of information. The network management system according to claim 2, wherein the network management system is reconfigured.