JP7734641B2 - Communication device, communication method, and communication program - Google Patents

Description

The present invention relates to a communication device, a communication method, and a communication program, and in particular to a communication device, a communication method, and a communication program that executes a program involving communication using a web browser equipped with a program execution engine with limited communication capabilities.

Web browser program execution engines place restrictions on the communication functions that programs can use, limiting some communication functions such as some protocols, two-way communication, and communication standby from external devices.

Non-Patent Document 1 discloses WebSocket as a standardized protocol technology for creating a bidirectional communication channel over a single TCP connection. WebSocket is a protocol that establishes a TCP connection using a pre-established HTTP connection using HTTP used on the Web, and bidirectionally exchanges non-HTTP messages between a web browser and a web server in frames with shorter header lengths than HTTP.

Patent Document 1 discloses a technology that consolidates communication paths in the browser by running a local proxy within the browser running on the device, and provides functions such as proxy authentication for applications running within the terminal and processing of page data displayed on the browser.

Patent No. 4353487

IETF RFC 6455

The WebSocket technology disclosed in Non-Patent Document 1 uses HTTP to establish connections, which places restrictions on communication between web servers and web browsers. Therefore, it cannot be used for communication between web browsers or for connecting to database servers that do not support HTTP.

Patent Document 1 assumes that HTTP will be used for communication via the local proxy, and does not convert protocols or change destination information in the local proxy. As a result, it is not possible to achieve two-way communication from a program running on a program execution engine within a web browser using a protocol other than HTTP that is not supported by the program execution engine, or by directly connecting to a program from an external device.

As such, the following challenges exist for a program running on a program execution engine within a web browser to achieve two-way communication with an external device.

First, a means is needed to extend the protocols and network functions available to programs running on the program execution engine within a web browser.

Secondly, when a message is sent from an external device to a program executed by a program execution engine within a web browser, a means is required to notify the program of the message contents.

The object of the present invention is to solve the above technical problems and provide a communications device, a communications method, and a communications program that implements protocols, network functions, and two-way communications compatible with the program execution engine within the web browser by placing a proxy function within the communications device and having the proxy function perform communications that the web browser cannot handle due to communication function limitations.

To achieve the above objectives, the present invention places a proxy function within the device and performs processing such as protocol conversion and destination information modification on messages sent and received between external devices, thereby compensating for communication functions that web browsers cannot support due to communication function limitations, thereby enabling message exchange using protocols and communication methods not provided by the program execution engine.

Messages sent by a program running on a web browser are sent using HTTP between the device and a proxy function running within the device, which then performs processes such as protocol conversion and destination changes to communicate with external devices using the desired protocol.

The present invention can be realized not only as a communications device equipped with such characteristic processing units, but also as a communications method for a communications device that includes steps in such characteristic processing, or as a communications program for a communications device that causes a computer to execute such steps.

The present invention achieves the following effects:

(1) By using a proxy function placed within the device to process messages, programs running within a web browser can exchange messages with external devices using protocols not provided by the program execution engine.

(2) A proxy function placed within the device processes and temporarily stores messages, allowing a program running within a web browser to receive messages sent from an external device.

(3) A proxy function located within the device processes the message and forwards it to a pre-established two-way communication channel, allowing a program running within a web browser to receive messages sent from an external device.

(4) By adding additional information when a program sends a message to the proxy function, the proxy function can select the content and method of message processing, such as the destination and protocol to be used.

(5) An identifier is assigned to each program, allowing the proxy function to distinguish between multiple programs running within a web browser, and the external device sends a message to the identified program. Therefore, even if the connection established between the program execution engine and the proxy function is terminated, the message can be sent to the correct program based on the identifier.

(6) The proxy function can obtain the control method for its own message processing unit from an external server, making it possible to change the control method collectively from an external server even when there are a large number of devices.

(7) By providing a control interface for the proxy function, the control method can be changed from an external device or a program running in a web browser, making it possible to change the content and method of message processing performed by the proxy function on a program-by-program basis.

1 is a functional block diagram showing the configuration of a main part of a communication device according to an embodiment of the present invention; 1 is a sequence flow (part 1) illustrating a procedure for a program to send a message to an external device. 10 is a sequence flow (part 2) illustrating a procedure for a program to send a message to an external device. FIG. 10 is a functional block diagram of programmatic message reception (Push). This is a sequence flow (part 1) showing the procedure for receiving (Pushing) a message by a program. This is a sequence flow (part 2) showing the procedure for receiving a message (Push) by a program. FIG. 10 is a functional block diagram of programmatic message reception (polling). This is a sequence flow (part 1) showing the procedure for receiving a message (polling) by a program. This is a sequence flow (part 2) showing the procedure for receiving a message (polling) by a program. This is a sequence flow (part 3) showing the procedure for receiving a message (polling) by a program. This is a sequence flow (part 4) showing the procedure for receiving messages (polling) by a program. FIG. 1 is a diagram showing an example of a scene in which the present invention is used.

Embodiments of the present invention will be described in detail below with reference to the drawings. Figure 1 is a functional block diagram showing the configuration of the main parts of a communication device 1 according to one embodiment of the present invention, which includes a web browser 10 and a proxy function 11. A web server 2 and an external device 3 are connected to the device 1 via a network.

Such a device 1 can be configured by implementing an application (program) that realizes each of the functions detailed below on a general-purpose computer or server equipped with a CPU, ROM, RAM, bus, interface, etc. Alternatively, it can be configured as a dedicated or single-function machine in which part of the application is implemented as hardware or software.

The web browser 10 includes a program execution engine 101 for executing programs loaded from the web server 2. The program execution engine 101 is a conventional engine that executes programs written in ECMAScript, JavaScript, Web Assembly (WASM), and other widely used web standard technologies.

Programs P1 and P2 are obtained from Web server 2, loaded into program execution engine 101, and execute the specified processing described in the program. When executing processing, programs P1 and P2 can exchange messages with external device 3 by calling the communication functions of program execution engine 101 via an interface provided by program execution engine 101. However, there are restrictions on the communication functions that programs P1 and P2 can use, and they are limited to communication functions for which program execution engine 101 provides an interface (hereinafter referred to as browser-compatible communication functions).

Browser-compatible communication functions include protocols such as HTTP (Hypertext Transfer Protocol), which is used for web communications, and WebSocket, a standard for two-way communication between web servers and web browsers over HTTP. Browser-compatible communication functions are, in principle, limited to client-type communication functions that connect to external servers, so it is not possible to connect directly from external device 3 to programs P1 and P2.

The proxy function 11 mainly consists of a local transmission/reception unit 111, a message processing unit 112, and a remote transmission/reception unit 113, and can compensate for the limited communication functions by executing communication functions that the web browser does not support due to the limitations of the communication functions.

The local sender/receiver 111 listens on one or more ports of the local loopback address within the device and executes the server function of the protocol included in the browser-compatible communication function. Programs P1 and P2 send messages on behalf of the external device 3 to the port on which the local sender/receiver of the local loopback address is listening. At this time, programs P1 and P2 add additional information to the message content, such as destination information for the external device 3 (the original connection destination) and the converted protocol, and can notify the proxy function 11 of the necessary information.

The local transmission/reception unit 111 transfers messages received from programs P1 and P2 to the message processing unit 112. The message processing unit 112 performs message processing such as protocol conversion and destination change according to predetermined processing content or additional information added by programs P1 and P2, and then transfers the message to the remote transmission/reception unit 113.

The remote transmission/reception unit 113 sends the message processed by the message processing unit 112 from the network interface of the device 10. This allows messages to be sent to the external device 3 using any protocol that the web browser 10 does not support. The remote transmission/reception unit 113 can also execute server functions using any protocol that the web browser 10 does not support, and wait for connections from the external device 3.

Figures 2A and 2B are sequence flows showing the steps for program P1 to send a message to external device 3.

At time t1, a user of device 1 accesses a URL from web browser 10 to launch program P1 on web server 2. At time t2, web browser 10 requests program P1 from web server 2. At time t3, web server 2 responds to the request by providing program P1 to web browser 10.

At time t4, the web browser 10 requests the program execution engine 101 to start program P1, and the program execution engine 101 starts program P1 at time t5. Program P1 performs a predetermined process at time t6 and requests the program execution engine 101 to call a communication function at time t7.

At time t8, the program execution engine 101 responds to the call request and sends a message via HTTP to the local transmission/reception unit 111. At time t9, the local transmission/reception unit 111 forwards the message to the message processing unit 112.

At time t10, the message processing unit 112 changes the destination of the message to the external device 3, converts the protocol from HTTP to MQTT, and transfers the message to the remote transmission/reception unit 113 at time t11. The remote transmission/reception unit 113 then transmits the transferred message to the external device 3 via MQTT at time t12.

At time t13, the external device 3 sends a message response to the remote transceiver unit 113 using MQTT. The remote transceiver unit 113 forwards the message response to the message processing unit 112 at time t14.

At time t15, the message processing unit 112 changes the destination of the transferred message response to program P1, converts the protocol from MQTT to HTTP, and sets a response code. Any code can be set as the response code depending on the content of the received response message. For example, if a PUBACK message, which indicates receipt of a message in MQTT, is received as a response, the HTTP response code can be set to 200 OK, indicating a successful request. Furthermore, if a response message is not received within a certain period of time, the HTTP response code can be set to 408 Request Timeout. The response message is transferred from the message processing unit 112 to the local transceiver 111 at time t16.

At time t17, the local transmission/reception unit 111 transfers the response message to the program execution engine 101 using the HTTP protocol. At time t18, the program execution engine 101 responds with a communication function to program P1. At time t19, program P1 processes the response result.

In this embodiment, a program running within a web browser can exchange messages with an external device 3 using a protocol not provided by the program execution engine, by having the proxy function 11 located within the device 1 process messages.

Figure 3 is a functional block diagram of message reception by program P1, and Figures 4A and 4B are sequence flows showing the steps for receiving a message. Here, we will explain an example in which device 1 receives a message sent by external device 3 using a push operation. In this embodiment, the HTTP server function is already activated in the local transceiver 111, and the MQTT server function is already activated in the remote transceiver 113.

At time t31, a user of device 1 accesses a URL for launching program P1 on web server 2 from web browser 10. At time t32, web browser 10 requests program P1 from web server 2. At time t33, web browser 10 obtains program P1, which web server 2 sends in response to the request.

At time t34, the web browser 10 requests the program execution engine 101 to start program P1, and the program execution engine 101 starts program P1 at time t35. At time t36, program P1 requests the program execution engine 101 to call a communication function, and the program execution engine 101 sends a program registration message to the local transmission/reception unit 111 via HTTP at time t37.

At time t38, the local transmission/reception unit 111 registers the program in the message processing unit 112. At time t39, the message processing unit 112 sends a program registration message response to the local transmission/reception unit. At time t40, the local transmission/reception unit 111 sends the program registration message response to the program execution engine 101 via HTTP.

At time t41, the program execution engine 101 responds with the registration result to program P1. At time t42, program P1 requests WebSocket from the program execution engine 101. At time t43, the program execution engine 101 sends a WebSocket connection request to the local transmission/reception unit 111 via HTTP. At time t44, the local transmission/reception unit 111 sends a WebSocket connection response to the program execution engine 101 via HTTP. At time t45, the program execution engine 101 reports the establishment of WebSocket to program P1.

After that, at time t51, the external device 3 requests the remote transmitter/receiver 113 to establish a connection using MQTT to send a message. At time t52, the remote transmitter/receiver 113 returns a connection establishment response using MQTT. At time t53, the external device 3 sends message M1 to the remote transmitter/receiver 113 using MQTT. In this embodiment, as shown in FIG. 3, message M1 is sent with the protocol "MQTT," the destination "Device 1," the identifier "86f021," and the data "abc."

At time t54, the remote transmission/reception unit 113 transfers the message M1 to the message processing unit 112. As shown in FIG. 3, at time t55, the message processing unit 112 converts the protocol of the message M1 from MQTT to WebSocket and changes the destination to program P1 [local host:35001], and at time t56, transfers the message m1, whose protocol and destination have been modified, to the local transmission/reception unit 111.

The local transmission/reception unit 111 transmits the received message m1 to the program execution engine 101 via WebSocket at time t57. The program execution engine 101 notifies the program P1 of the message m1 at time t58. The program P1 processes the message m1 at time t59 and transmits the processing result to the program execution engine 101 via WebSocket at time t60.

At time t61, the program execution engine 101 transmits the processing result to the local transmission/reception unit 111 via WebSocket. At time t62, the local transmission/reception unit 111 transfers the processing result to the message processing unit 112. At time t63, the message processing unit 112 changes the destination of the processing result to the external device 3, converts the protocol to MQTT, and transfers it to the remote transmission/reception unit 113 at time t64. At time t65, the remote transmission/reception unit 113 responds to the external device 3 by MQTT to notify that the message response has been completed.

Figure 5 is another functional block diagram of message reception by program P1, and Figures 6A to 6D are sequence flows showing the steps for receiving a message. Here, we will explain an example in which device 1 receives a message sent by external device 3 using a Polling operation. In this embodiment, the HTTP server function is activated in advance in the local transceiver unit 111, and the MQTT server function is activated in the remote transceiver unit 113.

At time t71, a user of device 1 accesses a URL for launching program P1 on web server 2 from web browser 10. At time t72, web browser 10 requests program P1 from web server 2. At time t73, web browser 10 obtains program P1, which web server 2 sends in response to the request.

At time t74, the web browser 10 requests the program execution engine 101 to start program P1, and the program execution engine 101 starts program P1 at time t75.

At time t76, program P1 requests the program execution engine 101 to call a communication function. At time t77, the program execution engine 101 responds to the call request and sends a program registration message to the local transmission/reception unit 111 via HTTP. At time t78, the local transmission/reception unit 111 registers the program in the message processing unit 112.

At time t79, the message processing unit 112 sends a program registration message response to the local transmission/reception unit 111. At time t80, the local transmission/reception unit 111 sends a program registration message response to the program execution engine 101 via HTTP. At time t81, the program execution engine 101 sends a registration result response to program P1.

After that, at time t91, external device 3 requests device 1 to establish a connection using MQTT in order to send a message. At time t92, the remote transmitter/receiver 113 replies with a connection establishment response using MQTT. At time t93, external device 3 transmits a message to the remote transmitter/receiver 113 using MQTT. In this embodiment, as shown in Figure 5, message M1 is transmitted, with the protocol set to "MQTT," the destination set to "device 1," the identifier set to "86f021," and the data set to "abc."

At time t94, the remote transmission/reception unit 113 transfers the message M1 to the message processing unit 112. At time t95, the message processing unit 112 extracts the identifier "86f021" and the data "abc" from the message M1, as shown in Figure 5, and stores them in the message cache 114 at time t96. Furthermore, at time t97, the message processing result is notified to the remote transmission/reception unit 113. Note that if the notified processing result is a failure, the remote transmission/reception unit 113 terminates the processing without responding.

After that, program P1 repeatedly requests the program execution engine 101 to call the communication function at a predetermined interval, and repeatedly receives messages via Polling. In this embodiment, when program P1 requests the program execution engine 101 to call the communication function at time t101, at time t102, the program execution engine 101 sends a reception confirmation message to the local transmission/reception unit 111 via HTTP. At time t103, the local transmission/reception unit 111 sends a reception confirmation to the message processing unit 112.

At time t104, when the message processing unit 112 requests the message cache 114 to retrieve a message, if the message is stored in the message cache 114, the message cache 114 sends a message response to the message processing unit 112 at time t105. At time t106, the message processing unit 112 changes the destination of the message to program P1 and adds an HTTP header to the message response. The message is transferred to the local sending/receiving unit 111 at time t107.

At time t108, the local transmission/reception unit 111 sends the message to the program execution engine 101 via HTTP. At time t109, the program execution engine 101 sends a communication function response to program P1. At time t110, program P1 processes the response result.

After sending the message to the local transceiver 111 at time t107, the message processing unit 112 notifies the remote transceiver 113 of the message transmission result at time t111. The remote transceiver 113 then sends a message transmission completion response to the external device 3 using MQTT at time t112.

In contrast, if no messages are stored in the message cache 114, the message cache 114 notifies the message processing unit 112 at time t113 that there are no messages.

At time t114, the message processing unit 112 notifies the local transmission/reception unit 111 that there are no messages. At time t115, the local transmission/reception unit 111 notifies the program execution engine 101 by HTTP that there are no messages. At time t116, the program execution engine 101 sends a communication function response to program P1.

In this embodiment, the proxy function 11 located within the device 1 processes and temporarily stores messages, allowing messages sent from the external device 3 to be received by a program running within the web browser 10.

Figure 7 shows an example of a usage scenario for the present invention, in which a user owns a smartphone 4 and a personal computer 5 as the device 1. The smartphone 4 is equipped with a VR program along with a web browser and proxy function, and the personal computer 5 is equipped with a video processing server program along with a web browser and proxy function.

The VR program on the smartphone 4 runs on a web browser, and by using a proxy function, it can send and receive video and control signals to and from the camera 6 (an IoT device) using MQTT, which is not supported by web browsers. It can also use a proxy function to link with applications such as container virtualization platforms on the cloud using the gRPC protocol, which is not supported by web browsers. It can also send and receive data and messages to and from the PC 5 using HTTP.

Similarly, the video processing server program on PC 5 runs on a web browser and can send and receive various data and messages with Camera 6 via MQTT, with the container virtualization platform on the cloud via the gRPC protocol, and with PC 5 via HTTP.

The use of proxy function 11 is not limited to proxy processing that enables the sending and receiving of messages, etc., but can also be used to provide encryption and authentication functions for messages sent by programs P1 and P2. This eliminates the need to implement encryption and authentication functions for each program, and allows for bulk processing by proxy function 11.

The proxy function 11 may also be configured to provide a function for permitting or prohibiting the sending of messages that programs P1 and P2 are attempting to send based on the destination and content of the message, or a function for sending messages sent by programs P1 and P2 to multiple pre-registered destinations.

Note that, although the above embodiment has been described using WebSocket as an example of a bidirectional communication channel, the present invention is not limited to this and can be implemented in the same way using other bidirectional communication channel technologies such as WebRTC.

Furthermore, according to the above embodiment, by implementing a proxy function on a device equipped with a web browser, it becomes possible to use communication functions such as protocols that are restricted by the web browser's program execution engine, two-way communication, and communication standby from external devices. This makes it possible to contribute to Goal 9 "Build resilient infrastructure and promote inclusive and sustainable industrialization" and Goal 11 "Make cities inclusive, safe, resilient and sustainable" of the United Nations-led Sustainable Development Goals (SDGs).

1...Device, 2...Web server, 3...External device, 10...Web browser, 11...Proxy function, 101...Program execution engine, 111...Local transmission/reception unit, 112...Message processing unit, 113...Remote transmission/reception unit, 114...Message cache

Claims (12)

A communication device that executes a program involving two-way communication using a web browser equipped with a program execution engine with limited communication capabilities,
Implement a proxy function that acts as a proxy for two-way communication with external devices via the network that web browsers cannot handle due to the limitations of the communication functions.
Acquire the program,
The program notifies the proxy function of additional information regarding destination changes and protocol conversions for two-way communications;
the proxy function processes the redirection and protocol conversion based on the additional information;
A communication device characterized in that the proxy function processes redirection and protocol conversion to cause the external device to receive communications from the program to the proxy function and to cause the program to receive communications from the external device to the proxy function . The communication device described in claim 1, characterized in that the proxy function provides the program with a push message reception function. The communication device according to claim 2 , wherein the proxy function converts an incoming message in a protocol that is not supported by the web browser into an incoming message in a protocol that is supported by the web browser. The communication device described in claim 1, characterized in that the proxy function provides the program with a message reception function via polling. 5. The communication device according to claim 4 , wherein the proxy function provides a server function for caching received messages, and responds to a polling request from the program by reading the cached received messages. The communication device according to claim 5 , wherein the proxy function converts the protocol of the cached received message into a protocol supported by a web browser. The communication device of claim 1, wherein the proxy function provides encryption functionality for outgoing messages. The communication device of claim 1, wherein the proxy function provides authentication functionality for outgoing messages. The communication device described in claim 1, characterized in that the proxy function allows or prohibits the sending of a message based on the destination and content of the message that the program is attempting to send. The communication device described in claim 1, characterized in that the proxy function sends messages that a program attempts to send to multiple pre-registered destinations. A communication method for a communication device that executes a program involving two-way communication in a web browser equipped with a program execution engine with limited communication capabilities, comprising:
Implement a proxy function that acts as a proxy for two-way communication with external devices via the network that web browsers cannot handle due to the limitations of the communication functions.
obtaining the program;
a step in which the program notifies the proxy function of additional information regarding destination redirection and protocol conversion of two-way communication;
said proxy function processing said redirection and protocol conversion based on said additional information;
A communication method for a communication device, characterized in that the proxy function processes destination changes and protocol conversions that cause the external device to receive communications from the program to the proxy function and cause the program to receive communications from the external device to the proxy function . A communication program for a communication device that executes a program involving two-way communication in a web browser equipped with a program execution engine with limited communication capabilities,
Implement a proxy function that acts as a proxy for two-way communication with external devices via the network that web browsers cannot handle due to the limitations of the communication functions.
obtaining the program;
a step in which the program notifies the proxy function of additional information regarding destination change and protocol conversion for two-way communication;
the proxy function processes the redirection and protocol conversion based on the additional information;
A communication program for a communication device, characterized in that the proxy function processes destination changes and protocol conversions that cause the external device to receive communications from the program to the proxy function and cause the program to receive communications from the external device to the proxy function .