JP2001094628A - Arrival confirmation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a data arrival confirmation method by which a fault location is located by specifying a reception node from which no reply comes so as to always keep the reliability of a network system. SOLUTION: In the network system that is provided with a plurality of nodes operated in autonomous distribution and where each of reception nodes 2 returns information denoting reception of data from a transmission node 1 to the transmission node 1, in the case that each of the reception nodes 2 returns information denoting the reception of the data to the transmission node 1, the transmission node 1 adds an ID to identify the reception nodes 2 to the data, the transmission node 1 stores the ID to a group ID table 1ca assigned respectively to the reception nodes 2 so as to locate a reception node 2 from which no reply comes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a network system having a plurality of nodes forming a group, which is used for a disaster prevention system, a security system, a home automation system, a building automation system, and the like. It relates to an arrival confirmation method for confirming whether or not arrival has been reached.

[0002]

2. Description of the Related Art A node for transmitting data (transmitting node)
With reference to FIG. 4, a description will be given of a conventional arrival confirmation method in group communication in which a Group frame is transmitted to a node (reception node) that receives data, and the reception node returns a Response frame. FIG. 4 is a schematic diagram showing a configuration of each node in the conventional group communication. FIG. 4A is a schematic diagram showing a configuration of a transmission node, and FIG.
Is a schematic diagram illustrating a configuration of a receiving node.

A transmitting node 1 and a plurality of receiving nodes 2 are connected by a network (not shown). The transmitting node 1 and the receiving node 2 are respectively provided with MAC processing units 1a and 2a and N
It has ET processing units 1b and 2b and APL processing units 1c and 2c.

[0004] The transmitting node 1 and the receiving node 2 use an ISO.
The configuration conforms to the OSI reference model of
The C processing units 1a and 2a perform the functions of the physical layer, the data link layer and the network layer, the NET processing units 1b and 2b perform the functions of the transport layer and the session layer, and the APL processing unit 1
c and 2c support the functions of the presentation layer and the application layer.

[0005] Each of the MAC processing units 1a and 2a of the transmission node 1 and the reception node 2 holds a source address SA which is its own MAC address and a group number GN indicating a group to which it belongs.

[0006] From the transmitting node 1 to the group (receiving node 2
), The data to be transmitted is passed from the APL processing unit 1c to the MAC processing unit 1c via the NET processing unit 1b, and the MAC processing unit 1c transmits the Group frame including the data. And flows a Group frame over the network.

[0007] The Group frame includes a transaction number TN indicating the number of the Group frame, data to be transmitted, information on the type of service, a source address SA, and a group number GN.

[0008] Upon receiving the Group frame, the MAC processing units 2a of all the receiving nodes 2 compare the group number GN held by itself with the group number GN in the Group frame, and determine the group to which the group belongs. It is determined whether the data is addressed to.

As a result, if the data is not data addressed to the group to which the user belongs, the Group frame is discarded. If the data is data addressed to the group to which the user belongs, the received G frame is discarded.
The transaction number TN in the group frame is recorded, and the data in the group frame is transferred to the APL processing unit 2c via the NET processing unit 2b.

The APL processing unit 2c processes data received from the MAC processing unit 2a via the NET processing unit 2b,
The processed data is again transmitted via the NET processing unit 2b.
Transfer to the MAC processing unit 2a.

[0011] Then, the MAC processing unit 2a returns a Response frame as an acknowledgment (an arrival message indicating that the data has arrived) to the transmitting node 1. Re
The response frame includes the data received from the APL processing unit 2c, and the transaction number TN and the source address SA in the received Group frame.

On the other hand, the MAC processing unit 1a of the transmitting node 1, which has transmitted the Group frame, transmits the returned R
The source address SA in the response frame determines whether the information is addressed to itself. If the information is not information addressed to itself, the Response frame is discarded. If the information is addressed to itself, the number of Response frames is counted.

The MAC processing unit 1a determines the number of receiving nodes 2 belonging to the transmission target group within a reference time determined by the network administrator,
If the number of the ponse frames does not match, the Group frame is again transmitted on the network.

Here, the reference time means that a Group frame is transmitted from the transmitting node 1 to the receiving node 2, and all the receiving nodes 2 that have received data addressed to the group to which the own node belongs transmit a Response frame to the transmitting node 1. This is the time required to reply, and is arbitrarily determined by the network administrator.

Upon receiving the Group frame and determining that the data is addressed to the group to which it belongs, the MAC processing unit 2a of the receiving node 2 determines whether the transaction number TN in the received Group frame has already been recorded. If the data has already been received, the Group frame is discarded. If the data has not been recorded, the Response frame is returned as data has not been received.

Then, the MAC processing unit 1a of the transmitting node 1
Finally, by comparing the number of receiving nodes 2 belonging to the group that transmitted data with the number of Response frames including the transaction number TN of the transmitted data, if the number of Response frames is not enough, If the information that the transmission has failed matches,
The information that the data transmission is successful is passed to the APL processing unit 1c via the NET processing unit 1b.

By doing so, for example, the Group frame transmitted to the receiving node 2 collides with another frame for some reason or the MA of the receiving node 2
The C processing unit 2a is executing another task, and the Group
Even if a transmission error such as not receiving a frame occurs,
Since the receiving node 1 retransmits the Group frame on the network, the data is reliably transmitted to the group to which the data is to be transmitted.

[0018]

However, according to the conventional arrival confirmation method, when some of the receiving nodes 2 in the group are out of order or the communication line is disconnected, the network administrator arbitrarily determines it. By repeating the retransmission of the Group frame up to the upper limit, it can be estimated that the receiving node 2 is faulty or disconnected. However, which receiving node 2 is faulty or the communication line is disconnected depends on a plurality of items. There has been a problem that a failure cannot be identified unless a certain receiving node 2 and communication line are checked one by one.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to replace a conventional MAC processing unit and NET processing unit without changing a receiving node that has not returned a response. It is an object of the present invention to provide a data arrival confirming method that can estimate a failure location by specifying the data and always maintain the reliability of the system.

[0020]

According to a first aspect of the present invention, there is provided a node having a plurality of nodes operating in an autonomous distributed manner, and receiving data when performing data communication between the plurality of nodes. From a node that transmits the data, information that the data has been received, in a network system that returns to the transmission node that transmits the data,
The node that receives the data, when returning information indicating that the data has been received to the node that transmits the data, the node that transmits the data is an ID for identifying the node that receives the data. And the node that transmits the data specifies the node that receives the data that has not returned by recording the ID in a memory area allocated to the node that receives the data.

According to the second aspect of the present invention, the first aspect is provided.
In the arrival confirmation method described above, in the recording format of the memory area, each recording unit is configured by one bit.

According to the third aspect of the present invention, there are provided a plurality of nodes operating in an autonomous distributed manner, and when performing data communication between the plurality of nodes, the node receiving data includes:
In a network system that returns information indicating that the data has been received from a node that transmits the data to a transmission node that transmits the data, a node that transmits the data receives the data that has transmitted the data. By comparing the number of nodes with the number of returned information indicating the reception, it is possible to select a conventional arrival confirmation method for performing arrival confirmation and the arrival confirmation method according to claim 1. .

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment A first embodiment according to the present invention will be described with reference to FIG.
1A and 1B are schematic diagrams illustrating a configuration of each node according to an embodiment of the present invention. FIG. 1A is a schematic diagram illustrating a configuration of a transmission node, and FIG. 1B is a schematic diagram illustrating a configuration of a reception node. is there.

In this embodiment, a group ID table 1ca in which an ID for the transmitting node 1 to identify the receiving node 2 is stored in the APL processing unit 1ca of the transmitting node 1 in comparison with the configuration of each node of the conventional technology. Is added to the APL processing unit 2c of the receiving node 2, the ID recording unit 2ca for recording the ID, and the ID from the ID recording unit 2ca.
A response processing unit 2cb for outputting the ID to the MAC processing unit 2a via the T processing unit 2b is added.

The ID recording unit 2ca stores an ID for the transmitting node 1 to identify itself (the receiving node 2), and outputs the ID in response to a request from the response processing unit 2cb. I have. The response processing unit 2cb
Receives the data from the MAC processing unit 2a, requests the ID from the ID recording unit 2ca, and outputs the ID to the MAC processing unit 2a via the NET processing unit 2b.

[0026] The MAC processing unit 2a includes a response unit TP including a transaction number TN, a source address SA, the ID, and an information Response indicating that data has arrived.
An nse frame is returned to the transmitting node 1. And R
MA of the transmitting node 1 that has received the response frame
The C processing unit 1a outputs the transaction number TN included in the Response frame and the ID to the APL processing unit 1c via the NET processing unit 1b.

In the group ID table 1ca of the APL processing section 1c, for example, a plurality of 1-byte data areas are formed, and each data area has a first receiving node 2, After that, the receiving nodes 2 are assigned in order, such as the second receiving node 2.

As an example, the APL processing unit 1c includes the first, third, and eighth receiving nodes 2 in the first group (group number GN is 1), the second, fourth, and ninth receiving nodes. Reference numeral 2 stores the receiving nodes 2 belonging to each group and their IDs, such as a third group (group number GN is 3).

The APL processing unit 1c determines which group is based on the transaction number TN received from the MAC processing unit 1a and which receiving node 2 is based on the ID.
The data is recorded in the data area corresponding to the ID in the group ID table 1ca so that it is clear which group and which receiving node 2 has sent a reply.

By doing so, the ID of the receiving node 2 for which data transmission has failed is stored in the group ID table 1c.
Since it is not recorded in a, the receiving node 2 from which data transmission has failed can be specified.

The group ID table 1ca of the APL processing unit 1c has been described as having a plurality of 1-byte data areas. However, the group ID table 1ca may be a data area in byte units and is limited to 1 byte. Not.

[Second Embodiment] Next, a second embodiment according to the present invention will be described with reference to FIG.
2A and 2B are schematic diagrams illustrating a configuration of each node according to an embodiment of the present invention. FIG. 2A is a schematic diagram illustrating a configuration of a transmission node according to the present invention, and FIG. FIG. 3 is a schematic diagram showing an example composed of one bit.

The ID recorded in the group ID table 1ca shown in the first embodiment requires a 1-byte data capacity. However, in a large-scale network system, the number of receiving nodes 2 also increases, and a data capacity equivalent to one byte multiplied by the number is required, so that effective use of memory resources cannot be achieved.

Therefore, each recording unit of the group ID table 1ca is composed of one bit. As an example, if the group ID table 1ca having a data capacity of 64 bits is used, 64 receiving nodes 2 can be managed. As in the first embodiment, each data area is provided with one end of the data area. The receiving nodes 2 are assigned in order, such as the first receiving node 2, the second receiving node 2, and so on.

As in the first embodiment, the first, third and eighth receiving nodes 2 include the first group (group number GN is 1), the second and fourth The ninth receiving node 2 stores the receiving node 2 belonging to each group and its ID, such as the receiving node 2 belonging to each group such as a third group (group number GN is 3).

The group ID table 1ca determines which group is based on the transaction number TN included in the Response frame from the receiving node 2 that has received the data and which bit is based on the ID, and sets the corresponding bit. (From 0 to 1).

In this way, the receiving node 2 from which data transmission has failed can be specified from the non-standing bits on the group ID table 1ca.

Third Embodiment Next, a third embodiment according to the present invention will be described with reference to FIG.
FIG. 3 is a schematic diagram showing a configuration of a transmission node used in the arrival method according to the present invention. This embodiment is characterized in that the APL processing unit 1c is provided with a selection unit 1cb, as compared with the first or second embodiment.

When performing data transmission, the selecting unit 1cb performs communication using a conventional arrival confirmation method capable of knowing only whether communication to the group has succeeded or failed, or to which receiving node 2 It is configured such that it is possible to select whether to perform communication using the arrival confirmation method of the first or second embodiment, in which it is possible to know whether the communication has failed.

[0040]

As described above, according to the first aspect of the present invention, since the ID of the receiving node for which data transmission has failed is not recorded in the group ID table, it is possible to specify the receiving node that has not returned a reply. In the case where the receiving node has failed or the communication line is broken, a defective part can be found only by examining the receiving node or the communication line connecting the receiving node, so that maintenance and management is significantly facilitated. The effect is that the reliability of the system can always be maintained.

According to the second aspect of the present invention, there is provided the first aspect.
In addition to the effect of the invention described in the above, the group ID table (memory area) using the method according to the first aspect of the present invention is configured such that each recording unit is composed of one bit, and one byte per one receiving node. Although a memory is required, the group ID table (memory area) of the present invention requires only one bit, so that the memory can be saved and the load on the CPU by reducing the data capacity can be reduced. Further, since a CPU having a small amount of memory and a low processing capacity can be used, there is an effect that cost can be reduced.

According to the third aspect of the present invention, if only the communication result is sufficient, the communication data capacity can be reduced (because ID data is not included in the Response frame). When it is necessary to specify a node that failed in data transmission, the arrival confirmation method according to the first aspect of the invention can be used, and the arrival confirmation method is selected according to the importance of communication. As a result, there is an effect that the CPU and the network resources can be effectively used.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a configuration of each node according to an embodiment of the present invention. FIG. 1A is a schematic diagram illustrating a configuration of a transmission node, and FIG. 1B is a schematic diagram illustrating a configuration of a reception node. FIG.

FIGS. 2A and 2B are schematic diagrams illustrating a configuration of each node according to an embodiment of the present invention. FIG. 2A is a schematic diagram illustrating a configuration of a transmission node according to the present invention, and FIG. FIG. 3 is a schematic diagram showing an example composed of one bit.

FIG. 3 is a schematic diagram illustrating a configuration of a transmission node according to an embodiment of the present invention.

4A and 4B are schematic diagrams illustrating a configuration of each node in the conventional group communication. FIG. 4A is a schematic diagram illustrating a configuration of a transmission node, and FIG. 4B is a schematic diagram illustrating a configuration of a reception node.

[Explanation of symbols]

 Reference Signs List 1 transmitting node (node transmitting data) 1ca group ID table (memory area) 1cc selecting unit 2 receiving node (node receiving data) 2ca ID recording unit 2cb response processing unit

Claims (3)

[Claims] A plurality of nodes operating in an autonomous distributed manner, and when performing data communication between the plurality of nodes, a node receiving data receives the data from a node transmitting the data. In a network system that returns information to the effect that the data is transmitted to a transmitting node that transmits the data, the node that receives the data transmits information that the data is received to a node that transmits the data. A node that transmits data adds an ID for identifying a node that receives the data, and the node that transmits the data stores the ID in a memory area assigned to each of the nodes that receives the data.
, A node that receives the data that has not been replied is specified. 2. The arrival confirmation method according to claim 1, wherein the recording format of the memory area is such that each recording unit is composed of one bit. 3. A system comprising a plurality of nodes operating autonomously in a distributed manner, wherein when performing data communication between the plurality of nodes, a node receiving data receives the data from a node transmitting the data. In a network system that returns information to the effect that the data is transmitted to a transmitting node that transmits the data, the node that transmits the data includes the number of nodes that receive the data that transmitted the data, An arrival confirmation method characterized in that a conventional arrival confirmation method for performing arrival confirmation and a arrival confirmation method according to claim 1 can be selected by comparing the number of pieces of information with each other.