JP3339537B2 - Communication control device and communication control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication controller corresponding to a failure which performs communication control when a failure occurs in a terminal in a network to which a plurality of terminals are connected.

[0002]

2. Description of the Related Art In a network to which a plurality of terminals are connected, a conventional method for exchanging information between terminals when a certain terminal has failed is as follows.
Here, FIG. 4 shows a case where the network is a home bus system (hereinafter, referred to as “HBS”) as an example.
A conventional technique will be described with reference to FIGS.

[0003] The HBS is a unified standard for a signal line system that mainly connects home automation equipment for home information processing. FIG. 4 is a configuration example of a network to which a plurality of home automation devices, that is, terminals 106a to 106c are connected. In HBS, FIG.
, Each terminal is connected to a home bus which is a common transmission path.

FIG. 5 is a block diagram showing a configuration of a conventional terminal. The conventional terminal 106 includes a communication unit 102, a device status display unit 103, a self address storage unit 104, and an application system processing unit 105. still,
In this configuration, the configuration of the terminal is classified into each block from the viewpoint of the function against the failure of the terminal. Communication unit 1
02 receives a frame flowing through the home bus 101 or transmits a frame to the home bus 101.

[0005] The device status display unit 103 indicates the soundness of the operation of the terminal. Specifically, a DC power source for driving a circuit of a home automation device, an AC power source for driving a cooling fan, and a rotation of a motor are provided. Output unit such as a temperature detection sensor and a temperature sensor. Self address storage unit 104
Is composed of a semiconductor memory or the like, and stores an address for uniquely identifying each terminal connected to the home bus.

The application system processing unit 105
Is composed of a CPU or the like, and controls communication via the home bus 101 and controls each component block.
Although not shown, the application system processing unit 105 includes a function as a home automation device unique to each terminal, for example, a function of an air conditioner generally used at home.

FIG. 6 is a diagram showing an example of a frame configuration transmitted and received between terminals in the HBS. The frame is
First priority code (PR) as shown
Starting from 61, a one-byte response code (ACK / NA
K) The configuration ends with 69. The data area (DATA) 66 therein further includes a header code (HD)
661, an operation code (OPC) 662, an operand (OPR) 663, and the like.

The exchange of frames between terminals in the conventional HBS configured as described above will be described with reference to FIGS. Now, by transmitting the control command to the terminal 106b with the terminal 106a serving as a controller,
It is assumed that the terminal 106b is remotely operated. FIG.
10 is a flowchart illustrating an operation in the terminal 106b.

FIG. 8 is a diagram showing exchange of frames between terminals in a normal state where no terminal failure has occurred. First, the terminal 106a transmits to the home bus 101 a frame 80a in which the destination address code (DA) 63 specifies the address of the terminal 106b.
The communication unit 102 of the terminal 106b receives the frame flowing on the network and passes it to the application system processing unit 105 (Step S71).

[0010] Application system processing unit 105
Determines whether the frame is a broadcast frame based on the value of the priority code (PR) 61 (step S7).
2). As a result of the determination, if it is determined that the frame is a broadcast frame, there is no response, and a predetermined process corresponding to the broadcast frame is performed (step S73). On the other hand, when it is determined that the frame is a non-broadcast frame (step S7).
2) Then, it is determined whether the frame is a frame addressed to itself (step S74). This determination is made based on whether or not the value stored in the self address storage unit 104 matches the value of the destination address code (DA) 63 in the frame.

If it is determined that the frame is addressed to itself, the data area (DA) 66 in the frame is decoded, and then information from the device status display unit 103 is obtained. It is determined whether or not the terminal is in a state in which the instructed control can be performed (step S
75). If it is determined that the device is normal, a 1-byte response (ACK) 80b is returned (step S7).
6) Perform the instructed control (step S77).

On the other hand, exchange of frames when a failure has occurred in the terminal 106b is as shown in FIG. That is, in step S75, the application system processing unit 105 of the terminal 106b
If it is determined that the instructed control cannot be performed, a one-byte response (NAK) 91b notifying the fact is returned (step S78), and the frame already received is discarded (step S79).

The transmitting terminal 10 that has learned that the communication has failed
6a normally retransmits the frame to see if the cause is accidental, but the HB in this example
According to the S standard, when a transmission error due to no response such as NAK or timeout is detected, retransmission is repeated up to three times until an ACK response is received. Therefore, such exchange between the terminal 106a and the terminal 106b is repeated three more times (92a to 94b).
b).

For the first time, the terminal 106a is connected to the terminal 10
In step 6b, it is recognized that a failure has occurred (step 95).

[0015]

However, such a conventional method has a problem that when a failure occurs in a terminal, a considerable amount of communication waste is caused.
That is, in the above example, the terminal 10 on the network
Terminals other than 6a and 106b have not yet recognized that a failure has occurred in terminal 106b. The terminal 106c is the terminal 106
In order to recognize the occurrence of the failure b, the same processing (96a to 99b) as that of the terminal 106a must be performed.

Further, since the terminal 106a does not know when the terminal 106b recovers from the failure, the terminal 106a transmits a frame to the terminal 106b if necessary (911a to 914).
b) must do. However, if the failure of the terminal 106b has not been recovered yet, the frame retransmission is repeated three times as described above. Further, the terminal 106b
Even if the terminal recovers from the failure,
a and 106c cannot immediately know the failure recovery. That is, a frame is transmitted to the terminal 106b (9
16a), and only after receiving the one-byte response (ACK) 916b, it is possible to recognize that the failure of the terminal 106b has been recovered (step 917).

As described above, in the conventional method, each terminal
Until communicating with the failed terminal, it was not possible to know that the terminal had failed. Therefore, useless communication is repeatedly performed, and other necessary communication is hindered. In particular, in a high-traffic network, it may be a fatal obstacle. Therefore, the present invention has been made in view of such a problem, and even when a terminal failure occurs in a network or recovers from the failure, the other terminals do not perform unnecessary communication. It is a first object of the present invention to provide a failure handling communication control device that supports a sound network that can recognize a failure.

A second object of the present invention is not only to know the occurrence / recovery of a failure, but also to allow each terminal to know the specific content of the failure and take appropriate measures according to the content. It is an object of the present invention to provide a fault-response communication control device that can perform the above.
Further, a third object of the present invention is to store frames to be transmitted when it is necessary to perform transmission to a failed terminal, and to store the frames when the failure is recovered. An object of the present invention is to provide a failure handling communication control device capable of transmitting a frame.

[0019]

In order to achieve the above object, a communication control apparatus according to the present invention sets a terminal state in a network connecting a plurality of terminals to specific information recognizable by another terminal. Setting means, and transmission means for transmitting the specific information to a plurality of terminals connected to the network, wherein the specific information is first information indicating that the notification is about an abnormality, 2nd shown
Only contains the information, the first information, any two bits of the second information
Or more fields are provided . Further, the specific information may further include third information indicating a terminal address in which an abnormality has occurred or has no abnormality.

Here, the transmitting means duplicates the specific information.
It is characterized by broadcasting to a number of terminals. In addition, the specific
The information is information indicating whether the specific information is broadcast.
It is characterized by including.

[0021]

[0022]

According to the communication control apparatus configured as described above, the setting means is capable of recognizing a state of a terminal in a network to which a plurality of terminals are connected so that another terminal can recognize the abnormality.
First information indicating that it is a report, and whether or not an abnormality has occurred
The specific information is set to the specific information including the second information shown , and the transmitting unit transmits the specific information to a plurality of terminals connected to the network. Here, the specific information further includes an error occurrence
Or including third information indicating a terminal address having no abnormality
It may be.

Here, the transmitting means transmits the specific information.
Broadcast to multiple terminals.

[0024] The transmitting means may determine whether the broadcast is to be made.
The specific information including the information indicating the information is transmitted.

[0025]

[0026]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram illustrating a configuration of a terminal provided with the failure handling communication control device according to the present embodiment. It differs from the conventional terminal shown in FIG. 5 in that a failure handling communication control device is added. That is, the terminal according to the present embodiment includes a failure frame assembling unit 107,
Failure occurrence detection unit 108, failure recovery detection unit 109, failure frame decoding unit 110, failure information storage unit 111, storage information transmission unit 112, transmission information storage unit 113, and transmission control unit 1.
14 is added.

The failure occurrence detecting section 108 includes an A / D converter (not shown), a reference state storage section, a comparator, and the like.
By comparing the operation state of the device indicated by the device state display unit 103 with a predetermined reference state, if the operation state of the device deviates from the reference state, that is, if a failure occurs in the terminal, this fact is notified. Inform the failed frame assembly unit 107.

The failure recovery detecting section 109 includes an A / D converter, a reference state storage section, a comparator, and the like (not shown) similar to the failure occurrence detecting section 108, and the operation state of the apparatus indicated by the apparatus state display section 103. By comparing the operation state of the device with the reference state given beforehand and returning to the reference state again after the operation state of the device has once deviated from the reference state, that is, when the terminal has recovered from the failure, the fact that the failure frame is assembled is determined. Part 107
Tell

The failure frame assembling section 107 assembles a frame for a predetermined simultaneous broadcast based on the failure contents and restoration contents detected by the failure occurrence detecting section 108 or the failure recovery detecting section 109, and divides the frame into the communication section 102. To the home bus 101 for transmission. Failure information storage unit 111
Is composed of a semiconductor memory or the like, and stores information on a failure of another terminal.

The failure frame decoding unit 110 decodes the received frame and, when determining that the frame is a frame for reporting a failure, sends the address of the terminal where the failure has occurred or has been recovered and the information on the failure. The information is stored in the failure information storage unit 111. The transmission information storage unit 113
The transmission frame to the failed terminal is accumulated and stored.

The transmission control unit 114 is provided with the failure information storage unit 11
The transmission destination of the frame is switched to the communication unit 102 or the transmission information storage unit 113 based on the information stored in the communication unit 102 and the transmission destination information of the frame transmitted from the application system processing unit 105. That is, if the destination of the frame is a non-failed terminal, the frame is sent to the communication unit 102 and transmitted to the terminal via the home bus 101. On the other hand, when the transmission destination of the frame is a failed terminal, the frame is stored in the transmission information storage unit 11.
3 to be stored.

The stored information transmitting section 112 reads out the frames stored in the transmitted information storing section 113 by referring to the information stored in the failure information storing section 111,
Send to the terminal that has recovered from the failure. FIG. 2 is a diagram illustrating an example of a frame configuration related to a failure transmitted and received between terminals according to the present embodiment in the HBS. FIG. 2 shows the operation code (OPC) 662 and the operand (OP) in the data area (DATA) 66 of the frame shown in FIG.
R) 663 only (hereinafter, referred to as “command”), and shows four types of formats (FIG. 2).
(1) & (2), (3) & (4), (5) & (6),
(7) & (8)) are defined. The operator can instruct each terminal in advance to report a failure by using a command of any one of these four types.

The reason why the values of the operation code (OPC) 662 are all "FE" (hex) is to use a code that is not reserved in the HBS standard. Is defined as a command for The value of the first byte of the operand (OPR) 663 is for distinguishing the illustrated eight types of commands.

The commands shown in FIGS. 2A and 2B are commands indicating only occurrence / recovery of a failure, and have an advantage that the frame length can be kept short. FIG.
(3) and (4) are obtained by adding information of a terminal address at which a failure has occurred / recovered to the command of FIGS. 2 (1) and (2), and each terminal that has received a frame including this command, The failed terminal can be known from the command at the layer 7 level without having to check the address (SA) 62 at the layer 2 level of the HBS protocol. Therefore, it is possible to reduce the processing load at the application level.

The commands shown in FIGS. 2 (5) and (6) are obtained by adding information relating to the failure content to the commands of FIGS. 2 (1) and (2). The terminal can obtain more detailed information as well as whether or not a failure has occurred / recovered. For example, by adding a code corresponding to the content of a predefined failure, the terminal receiving this frame predicts the time until the failed terminal recovers or provides assistance for recovery. And so on, which leads to an improvement in network reliability.

The commands shown in FIGS. 2 (7) and (8) are the commands of FIGS. 2 (1) and (2) added with the terminal address at which the failure occurred / recovered and information on the content of the failure. 2 (3), (4) and (5), (6) can be obtained in combination. In the conventional HBS configured as described above, exchange of frames between terminals will be described with reference to FIG.

FIG. 3 shows the exchange of frames between the terminals when a failure occurs in the terminal 106b and the failure is subsequently recovered. The failure occurrence detection unit 108 of the terminal 106b knows that a failure has occurred in the terminal by comparing the state indicated by the device state display unit 103 with a predetermined reference state, and notifies the failure frame assembling unit 107 of the fact. (Step S30).

The failure frame assembling section 107, having received the notification from the failure occurrence detecting section 108, assembles a frame for reporting its own failure, and combines the frame with the communication section 102.
(Step S31). Specifically, the failure frame assembling unit 107 converts a command in a format designated in advance from the failure occurrence commands (FIGS. 2 (1), (3), (5), (7)) shown in FIG. (DATA) 66, the self address storage unit 104
, And sets the source address code (SA) 62 and the operand (OPR) 663, sets the priority code (PR) 61 to the value of the broadcast frame, and assembles the frame. 10
Send to 2 for simultaneous broadcast.

Terminal 1 that has received the broadcast frame
At 06a, the failed frame decoding unit 110 determines whether the source address (SA) 62 or the terminal address 23
c and 27c, it is recognized that a failure has occurred in the terminal 106b.
11 (step S32a).

The transmission control unit 114 is provided with the failure information storage unit 11
When a frame transmission to the failed terminal 106b occurs by referring to the information stored in No. 1, the frame is stored in the transmission information storage unit 113 without being transmitted to the communication unit 102 and stored. deep. These operations at the terminal 106a are the same for all other terminals on the network (for example, the terminal 106c) (step S32).
b).

Thus, each terminal can know the occurrence of a failure at the same time as the occurrence of the failure, and can avoid transmission and retransmission of useless frames as in the conventional terminal. Further, when the simultaneously broadcasted frame has information on the details of the failure, each terminal can take an appropriate action according to the details of the failure at an early stage.

Next, when the failure of the terminal 106b is recovered, the failure recovery detecting section 109
Is compared with a reference state given in advance to know that the fault that has occurred has been recovered, and that fact is notified to the faulty frame assembling section 107 (step S
33). Upon receiving the notification from the failure recovery detecting unit 109, the failure frame assembling unit 107 assembles a frame for notifying the recovery of its own failure, and combines the frame with the communication unit 10
2 for simultaneous broadcast (step S34).

More specifically, the failed frame assembling unit 107
Is the failure recovery command shown in FIG. 2 (FIG. 2 (2)
(4) A command of a format designated in advance from (6) and (8) is set in the data area (DATA) 66, the self address stored in the self address storage unit 104 is read, and the source address code (SA) is read. ) 62 and operand (OPR) 663, the priority code (PR) 61 is set to the value of the broadcast frame, and after assembling the frame, the frame is sent to the communication unit 102 for simultaneous broadcast.

Terminal 1 that has received the broadcast frame
In 06a, the failed frame decoding unit 110 determines whether the source address (SA) 62 or the terminal address 24
c and 28c, it is recognized that the failure that has occurred in the terminal 106b has been
Information 26c and 28d on address b and recovery from failure
Is stored in the failure information storage unit 111 (step S35).
a).

The stored information transmitting unit 112 refers to the information stored in the failure information storage unit 111, reads out a frame to be transmitted to the terminal 106b whose failure has been recovered from the transmission information storage unit 113, and transmits the frame to the terminal 106b. I do. The transmission control unit 114 switches the transmission destination of the frame transmitted from the application system processing unit 105 to the communication unit 102 by referring to the information stored in the failure information storage unit 111.

These operations at the terminal 106a are the same for all other terminals on the network (for example, the terminal 106c) (step S35b). in this way,
I want to send a frame to terminal 106b,
The terminal that has refrained from transmitting the frame because of the failure has immediately recognized that the failure of the terminal 106b has been recovered, and
6b can be resumed. This makes it possible to avoid useless transmission and retransmission of frames, which are performed by conventional terminals, even at the time of recovery from a failure.

[0047]

As is apparent from the above description, according to the present invention, when a terminal failure occurs or recovers from the failure in the network, the terminal itself broadcasts a frame relating to the failure simultaneously. All other terminals on the network can obtain information about the failure without performing useless communication with the failed terminal and at the time when they occur.

Further, since the broadcast frame includes not only the presence / absence of the occurrence / recovery of the failure but also information on the specific contents of the failure, each terminal can make an appropriate operation according to the contents. Measures can be taken. Further, the terminal receiving the frame related to the failure stores the frames when it is necessary to transmit the frames to the failed terminal, and stores the frames stored when the failure is recovered. Can be sent.

As described above, according to the present invention, even when a terminal failure occurs in the network, an increase in network traffic due to useless communication can be avoided. Can be taken early, so that there is an effect that a sound network can be constructed.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a terminal provided with a failure handling communication control device according to an embodiment;

FIG. 2 is a diagram illustrating an example of a frame configuration related to a failure transmitted and received between terminals according to the embodiment;

FIG. 3 is a diagram illustrating exchange of frames between terminals when a terminal failure occurs in the present embodiment and the terminal recovers thereafter.

FIG. 4 is a configuration example of a network to which a plurality of terminals are connected.

FIG. 5 is a block diagram showing a configuration of a conventional terminal.

FIG. 6 is a diagram showing an example of a conventional frame configuration transmitted and received between terminals.

FIG. 7 is a flowchart showing the operation of a conventional terminal.

FIG. 8 is a diagram illustrating a conventional frame exchange between terminals in a normal state in which no terminal failure occurs.

FIG. 9 is a diagram showing a conventional frame exchange between terminals when a terminal failure occurs.

[Explanation of symbols]

 102 communication unit 107 failure frame assembling unit 108 failure occurrence detection unit 109 failure recovery detection unit 110 failure frame decoding unit 111 failure information storage unit 112 accumulated information transmission unit 113 transmission information accumulation unit 114 transmission control unit

Continuation of the front page (56) References JP-A-61-212145 (JP, A) JP-A-3-145846 (JP, A) JP-A-55-39438 (JP, A) JP-A-4-125766 (JP) JP-A-2-2247 (JP, A) JP-A-63-300349 (JP, A) JP-A-4-196842 (JP, A) JP-A-63-263940 (JP, A) 55-91252 (JP, U) (58) Fields studied (Int. Cl. ⁷ , DB name) H04L 12/40

Claims (8)

(57) [Claims] 1. A setting unit for setting a state of a terminal in a network to which a plurality of terminals are connected to specific information recognizable by another terminal, and transmitting the specific information to a plurality of terminals connected to the network. Means, wherein the specific information is a
And one of the information, the second information indicating the presence or absence of abnormality seen including, first
Both 1st information and 2nd information are fields of 2 bits or more.
A communication control device characterized in that the communication control device is provided with a password. 2. The communication control device according to claim 1, wherein the specific information further includes third information indicating a terminal address where an abnormality has occurred or has no abnormality. 3. The communication control device according to claim 1, wherein the transmission unit broadcasts the specific information to a plurality of terminals. 4. The communication control device according to claim 1, wherein the specific information includes information indicating whether the specific information is broadcast. 5. A setting step of setting a state of a terminal in a network connecting a plurality of terminals to specific information recognizable by another terminal, and transmitting the specific information to a plurality of terminals connected to the network. A step indicating that the specific information is a notification regarding an abnormality.
And one of the information, the second information indicating the presence or absence of abnormality seen including,
Neither the first information nor the second information has a 2-bit or more field.
Communication control method, wherein a field is provided . 6. The communication control method according to claim 5, wherein the specific information further includes third information indicating a terminal address where an abnormality has occurred or has no abnormality. 7. The communication control method according to claim 5, wherein the transmitting step broadcasts the specific information to a plurality of terminals. 8. The communication control method according to claim 5, wherein the specific information includes information indicating whether the specific information is broadcast.