JP5637406B2 - Data transmitting apparatus and program - Google Patents

Description

The present invention relates to a data transmission device, about your and program.

  In a conventional server-client system, for example, there is a server-based computing system (SBC) in which a desired application program is activated and executed on the server device side by remote operation from the client device. In this SBC system, display drawing data that is processed and updated on the server device side in response to an operation input of the client device is transmitted and transferred from the server device to the client device every time the drawing is updated. As a result, the client device only needs to have a minimum function such as display and input, and resources such as applications are centrally managed by the server device.

  As described above, since the application program is executed on the server device, the SBC system can realize a highly functional computing environment even when the performance of the client device is low.

  Conventionally, the SBC system is designed on the premise of a high-speed network having no delay such as an in-house LAN (Local Area Network). However, when the amount of screen update data is large or the network communication speed (bandwidth) is low (narrow), the screen drawing data generated by the server device in response to the operation input of the client device is It takes time until the data is transmitted and transferred to the client device and is completed and displayed as one screen, which causes a problem of poor responsiveness.

  Therefore, in order to improve the user's apparent response in the client device, a screen transfer device that transmits screen drawing data with low data quality with a small amount of data first, and then transmits high-quality screen drawing data at intervals. (For example, refer to Patent Document 1).

  Further, the drawing data for display transmitted and transferred from the server device to the client device is accumulated and stored in the client device, so that it is not necessary to repeatedly transmit the drawing data once transmitted from the server device, A client server system that can reduce the load on the server device and can improve the operation response of the drawing update as viewed from the client device has been considered (for example, see Patent Document 2).

JP 2006-246153 A JP 2007-065835 A

  In the conventional client-server system, past drawing data once transmitted and stored in the client device can be displayed with good operation response without waiting for re-transmission from the server device. When requesting acquisition of a page and displaying the long page data while scrolling, the page data in the area corresponding to the scroll instruction is transferred to the client device each time the scroll operation is performed. It cannot be displayed with good operation response.

The present invention has been made in view of such problems, the data transmission apparatus becomes possible to display operation with good response, and to provide a contact and program.

Data transmission device according to claim 1, and remembers to Lud over data storage means data as divide divided data, into each of the divided data stored by the data storage means of this and charts setting means for setting a forward position, a transmission timing determining means for determining a timing of transmitting data in accordance with the operation state of the apparatus, the timing of the data transmission is determined by the transmission timing determination unit, before Kide is characterized by comprising a Lud over data transmission means to transmit to the slave have terminal device to order set in front Symbol Position setting means the stored divided data by chromatography data storage means.

According to the present invention, a data transmission apparatus becomes possible to display operation with good response, it can provide a contact and program.

1 is a block diagram showing a configuration of an SBC (Server Based Computing) system according to an embodiment of the present invention. The block diagram which shows the circuit structure of the server apparatus 10 in the said SBC system. The block diagram which shows the circuit structure of the client apparatus 20 in the said SBC system. FIG. 3 is a diagram showing a configuration of software modules in the server device 10 and the client device 20. The figure which shows the main data memories prepared in RAM14 of the said server apparatus 10. FIG. FIG. 3 is a diagram showing a relationship between drawing data G of a Web page HP generated on the client frame buffer 14a of the server device 10 and cache data CD acquired along with generation of the drawing data G. The figure which shows the relationship between the area | region of the drawing data G with respect to the area | region of the web page HP acquired by the application (web browser) of the said server apparatus 10, and scroll width (movement amount) Ds. The figure which shows the transmission format Fhp of the web page HP acquired by the application (web browser) of the said server apparatus 10. FIG. The figure which shows the end format Fhpe of the web page HP acquired by the application (web browser) of the said server apparatus 10. FIG. The transfer priority order to the client device 20 as the cache data CD preset in units of the scroll width (movement amount) Ds of the Web page HP acquired by the application (Web browser) of the server device 10 is set. FIG. The figure which shows the prefetch cache FIFO memory 14d in the prefetch cache memory 14X of the said server apparatus 10, the cache state management buffer 14e, and the screen transmission FIFO memory 14c. The figure which shows the content of the cache data memorize | stored in the prefetch cache FIFO memory 14d of the said server apparatus 10. FIG. The figure which shows the content of the cache status information memorize | stored in the cache status management buffer 14e of the said server apparatus 10. FIG. The flowchart which shows the outline | summary of the cache acquisition transmission process and the scroll corresponding | compatible transmission process which the server apparatus 10 of the said SBC system performs. It is a flowchart which shows the detailed process of acquisition (b) and management / transmission (c) of the cache data CD included in the cache acquisition transmission process of the server device 10. The flowchart which shows the detailed process of step c2-c4 in the said FIG. The flowchart which shows the input event recording process and cache transmission timing [Level-3] determination process which the server apparatus 10 of the said SBC system performs. FIG. 17 is a flowchart showing cache data transmission processing executed following the cache data acquisition processing executed in accordance with the flowcharts shown in FIGS. 15 and 16 and storage processing in the prefetch cache FIFO memory 14d. The figure which shows the transmission format Tds of the cache data accompanying the cache data transmission process in the said FIG. The flowchart which shows the detail of the scroll corresponding | compatible transmission process which the server apparatus 10 of the said FIG. 14 (B) performs. The figure which shows the content of the cache data memorize | stored in the prefetch cache memory 24a of the client apparatus 20 of the said SBC system. 5 is a flowchart showing display processing of the client device 22.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of an SBC (Server Based Computing) system according to an embodiment of the present invention.

  This SBC system includes a server device 10 and a plurality of client devices (thin clients) 20 connected to a network N composed of a wired or wireless LAN (Local Area Network) or WAN (Wide Area Network).

  The server device 10 has a plurality of application programs such as a text creation processing program, a Web browser program, a spreadsheet processing program, and a mail processing program, and an operation input from the client devices 20 connected to the server device 10 ( It is activated in response to the (input event) signal and executes its processing.

  In the server device 10, the display output drawing data G generated on the client frame buffer RAM 14a (see FIG. 2) in accordance with the execution of the application program according to the operation input signal from the client device 20,. , Image transmission and command transmission are combined and transferred to the access source client device 20.

  Then, in the client devices 20,..., The drawing data G transferred from the server device 10 is expanded in the frame buffer RAM 25 (see FIG. 3) and displayed on the display screen of the display device 26.

  That is, each client device (Thin client) 20 in the SBC system has an input function corresponding to a user operation such as a keyboard and a mouse and an output function to an LCD display unit and a printer as main functions. The server device 10 does not have at least various application functions and data file management functions.

  And the data file produced | generated with the various processes started and performed in the server apparatus 10 according to the operation input (input event) signal from the client apparatus 20 ... is fundamentally in the said server apparatus 10. Alternatively, it is stored and stored for each user account or as a shared file in a storage device such as a magnetic disk managed and managed by the server device 10.

  FIG. 2 is a block diagram showing a circuit configuration of the server device 10 in the SBC system.

  The server device 10 includes a CPU 11 as a computer, and a ROM 13, a RAM 14, a frame buffer RAM 15, and a display device 16 are connected to the CPU 11 via a bus 12.

  Further, a communication I / F (interface) 19 with an input device 17 such as a keyboard and a mouse, an external storage device 18, a client device 20,.

  The CPU 11 controls the operation of each part of the circuit by using the RAM 14 as a working memory in accordance with a system program or various application programs stored in advance in the program memory 13a of the ROM 13, and controls key input signals from the input device 17 and communication I / O. The various programs are started and executed in response to a processing command (input event) signal corresponding to a user operation from the client device 20 received via F19.

  In this server device 10, various data generated in accordance with an application program activated / executed in response to an input event signal from the client device 20 is stored in the external storage device 18 in association with the user ID, for example. . The drawing data G for client display is generated using the client frame buffer RAM 14 a in the RAM 14, transferred from the communication I / F 19 to the client device 20, and displayed.

  The RAM 14 includes a prefetch cache memory 14X. In the prefetch cache memory 14X, drawing data G to be displayed on the display screen (26) of the client device 20 is generated in the client frame buffer RAM 14a in accordance with an application program executed in response to an input event signal from the client device 20. As a result, all the data including the area outside the display screen continuously with the drawing data G is stored as cache data. For example, when an input event from the client device 20 is an event for requesting display of the Web page HP, the client device 20 uses the entire data of the Web page HP acquired by the Web browser program of the server device 10 in response to this event. The drawing data G matching the display screen (26) is generated and stored in the client frame buffer RAM 14a (see FIG. 6A), and the entire data of the Web page HP (see FIG. 6B). Is stored in the prefetch cache memory 14X as cache data CD.

  The cache data CD stored in the prefetch cache memory 14X is transferred to the client device 20 at an appropriate timing set separately from the transfer processing of the drawing data G generated in the client frame buffer RAM 14a. It is stored in the memory 24a (see FIG. 3).

  If the drawing data G generated in the client frame buffer RAM 14a is the same as the cache data already stored in the prefetch cache memory 24a, the cache data associated with the cache data is stored. Only the ID is transmitted to the client device 20.

  On the other hand, drawing data to be displayed on the display device 16 of the server device 10 itself is generated on the frame buffer RAM 15.

  FIG. 3 is a block diagram showing a circuit configuration of the client device 20 in the SBC system.

  The client device 20 includes a CPU 21 as a computer, and a ROM 23, a RAM 24, and a frame buffer RAM 25 are connected to the CPU 21 via a bus 22. Then, the drawing data G (see FIG. 6A) written in the frame buffer RAM 25 is displayed on the display screen of the display device 26.

  The CPU 21 is connected to an input device 27, an external storage device 28, and a communication I / F (interface) 29 with the server device 10 via the bus 22.

  The CPU 21 controls the operation of each part of the circuit by using the RAM 24 as a working memory in accordance with a system program stored in the program memory 23a of the ROM 23. The CPU 21 receives the key input signal from the input device 27 via the communication I / F 29. The system program is activated and executed in response to an application response signal, transfer drawing data G, cache data CD, and the like from the server apparatus 10 to be executed.

  In the client device 20, various data generated by executing the application program in the server device 10 is appropriately read and stored in the external storage device 28, and the generated drawing data G for transfer is The data is developed in the frame buffer RAM 25 and displayed on the display device 26.

  Note that cache data such as a web page HP read from the prefetch cache memory 14X of the server device 10 and transferred to the client device 20 is stored in the prefetch cache memory 24a. When a cache ID is received from the server device 10a in response to an input event from the client device 20, cache data associated with the cache ID is read from the prefetch cache memory 24a, and The data is expanded and displayed on the frame buffer RAM 29.

  FIG. 4 is a diagram showing the configuration of software modules in the server device 10 and the client device 20.

  The server control program stored in the program memory 13a of the server device 10 includes an RTT (Round Trip Time) measurement module 13a1, a screen control module 13a2, and a communication module 13a3.

  The RTT measurement module 13a1 has a function of measuring the degree of transmission delay with the client device 20 in the network N and notifying the measurement result to the screen control module 13a2.

  The screen control module 13a2 activates an application program corresponding to an input event from the client device 20 and generates drawing data G to be displayed on the display screen (26) of the client device 20 on the client frame buffer RAM 14a ( (See FIG. 6A). Further, when the drawing data G for client display is generated, a series of drawing data continuous to the drawing data G (for example, as shown in FIG. 6B, when an access event to the Web page HP occurs) Obtains the data (HP) of the entire page and stores it as cache data CD in the prefetch cache memory 14X. Then, the cache data CD stored in the pre-read cache memory 14X is divided into three areas [Level-1 / Level-2 / Level-3] (see FIG. 10) in order of high possibility of screen scrolling. The first timing immediately after the start of acquisition of drawing data (immediately after the start of loading of the Web page HP), the second timing immediately after the end of acquisition of the series of drawing data (immediately after the end of loading of the Web page HP), and the client device The client device 20 is based on the status of the input event from 20, the measurement result of the transmission delay notified from the RTT measurement module 13a1, and the third timing according to the waiting state for transferring the drawing data G to the client device 20. Send to. In addition, when the drawing data G for client display is generated, if cache data matching the drawing data G exists in the prefetch cache memory 14X, the transmission schedule control function for transmitting the cache ID is provided. .

  The communication module 13a3 has a function of passing the input event data and RTT measurement data received from the client device 20 to the screen control module 13a2 and the RTT measurement module 13a1, and the RTT measurement data received from the RTT measurement module 13a1. And has a function of transmitting the drawing data G, the cache data CD, and the cache ID received from the screen control module 13a2 to the client device 20.

  On the other hand, the client control program stored in the program memory 23a of the client device 20 includes a communication module 23a1, an input module 23a2, and a screen display module 23a3.

  The communication module 23a1 transmits / receives data for RTT measurement to / from the server device 10 and the input event data received from the input module 23a2 to the server device 10, and is received from the server device 10. It has a function of delivering the drawing data G for display, the cache data CD, and the cache ID to the screen display module 23a3.

  The input module 23a2 has a function of delivering input event data corresponding to a user operation to the communication module 23a1.

  The screen display module 23a3 has a function of developing the display drawing data G received from the communication module 23a1 in the frame buffer RAM 25 and displaying it on the display device 26 (see FIG. 6A). In addition, the cache data CD received from the communication module 23a1 is stored in the prefetch cache memory 24a. Further, the cache data CD corresponding to the cache ID received from the communication module 23a1 is read from the prefetch cache memory 24a, developed in the frame buffer RAM 25, and displayed on the display device 26.

  FIG. 5 is a diagram showing main data memories prepared in the RAM 14 of the server device 10.

  In addition to the client frame buffer RAM 14a, the RAM 14 includes an RTT memory 14b, a screen transmission FIFO memory 14c, a prefetch cache memory 14X (prefetch cache FIFO memory 14d / cache state management buffer 14e / cache transmission timing level memory 14f), input An event time stamp memory 14g and the like are prepared.

  The RTT memory 14b stores a transmission delay time t between the client device 20 measured by the RTT measurement function of the RTT measurement module 13a1.

  In the screen transmission FIFO memory 14c (see FIG. 11C), the drawing data G (see FIG. 6A) generated by the client frame buffer RAM 14a is buffered as data to be transferred to the client device 20. At this time, only the data in the rectangular area including the portion updated by comparison with the previous drawing data G (n-1) is, for example, the screen scroll set by the application that generated the drawing data G. Is stored in units of width Ds (see FIG. 7).

  In the prefetch cache FIFO memory 14d (see FIGS. 11A and 12), along with the generation of the drawing data G (see FIGS. 6A and 7) for the client frame buffer RAM 14a, the drawing data G is stored. A series of continuous data (for example, the entire data of the Web page HP to be accessed) is buffered as cache data CD. At this time, for example, the drawing data G is generated in the same manner as the screen transmission FIFO memory 14c. Stored in units of screen scroll width Ds (see FIG. 7) set by an application (for example, a Web browser). As the cache data in units of the screen scroll width Ds, a flag indicating the data size (width × height), URL-ID, cache ID, and transfer priority level (Level-1 or level) is included along with the data body. 2 or 3), a data compression method (0: JPEG / 1: PNG /...) Is added and stored (see FIG. 12).

  In the cache status management buffer 14e (see FIGS. 11B and 13), status information (each cache data in units of screen scroll width Ds) stored in the prefetch cache FIFO memory 14d (see FIG. 12) ( Data-specific hash value / cache ID / untransmitted: 0 or transmitted: 1) Jds is stored.

  In the cache transmission timing level memory 14f, the current level for determining the timing to transfer the cache data stored in the prefetch cache FIFO memory 14d to the client device 20 is immediately after the start of the acquisition of the cache data (in the Web page). [Level-1] immediately after the start of loading), [Level-2] immediately after the end of cache data acquisition (immediately after the end of loading of the Web page), and the RTT measurement module after a certain time has elapsed since the input event from the client device 20 [Level-3] when the measurement result of the transmission delay notified from 13a1 is equal to or lower than the threshold and the number of reservations for waiting to transfer the drawing data G to the client device 20 in the screen transmission FIFO memory 14c (in units of Ds) is equal to or lower than the threshold. Set as

  In the input event time stamp memory 14g, the time stamp data acquired with the input event from the client device 20 is updated and stored for each input event.

  FIG. 6 is a diagram showing the relationship between the drawing data G of the Web page HP generated on the client frame buffer 14a of the server device 10 and the cache data CD acquired along with the generation of the drawing data G. .

  FIG. 7 is a diagram showing the relationship between the area of the drawing data G and the scroll width (movement amount) Ds with respect to the area of the Web page HP acquired by the application (Web browser) of the server device 10.

  FIG. 8 is a diagram showing a transmission format Fhp of the Web page HP acquired by the application (Web browser) of the server device 10.

  FIG. 9 is a diagram showing the end format Fhpe of the Web page HP acquired by the application (Web browser) of the server device 10.

  For example, when the input event from the client device 20 is an access request to the Web page HP, the application (Web browser) of the server device 10 is activated, and the Web page HP data corresponding to the user-specified URL is shown in FIG. It is acquired according to the formats Fhp and Fhpe in FIG.

  At this time, drawing data G in which data from the top of the Web page HP is written is generated on the client frame buffer RAM 14a in accordance with the display screen size (26) of the client device 20, and the entire Web page HP is also generated. Are written in the prefetch cache memory 14X as cache data CD.

  The data of the Web page HP written in the prefetch cache memory 14X is managed in units of data of the scroll width (movement amount) Ds according to the “scroll pixel value” described in the transmission format Fhp.

  FIG. 10 shows how the client device 20 as the cache data CD set in advance in units of the scroll width (movement amount) Ds of the Web page HP acquired by the application (Web browser) of the server device 10. It is a figure which shows transfer priority.

  The drawing data G generated in the client frame buffer RAM 14a in response to an input event (Web page access request) from the client device 20 matches the display screen size of the client device 20 from the top of the Web page HP to be accessed. When the entire data of the Web page HP is generated and stored in the prefetch cache memory 14X as the cache data CD, the scroll width (movement amount) having the highest possibility of screen scrolling immediately below the drawing data G is generated. An area [Ds × n] that is n times Ds is set to the first priority transfer level [Level-1]. Subsequently, after the area [Ds × n] of the Web page HP set to the first priority transfer level [Level-1], the scroll width (movement amount) Ds that has the highest possibility of screen scrolling is m times as large. The area [Ds × m] is set to the second priority transfer level [Level-2]. The area up to the lower end of the Web page HP following the area [Ds × m] of the Web page HP set to the second priority transfer level [Level-2] and the area corresponding to the drawing data G are: In either case, the third-priority transfer level [Level-3] is set.

  FIG. 11 is a diagram showing a prefetch cache FIFO memory 14d, a cache state management buffer 14e, and a screen transmission FIFO memory 14c in the prefetch cache memory 14X of the server device 10.

  FIG. 12 is a diagram showing the contents of the cache data stored in the prefetch cache FIFO memory 14d of the server device 10.

  FIG. 13 is a diagram showing the contents of the cache state information stored in the cache state management buffer 14e of the server device 10.

  As described above, the prefetch cache FIFO memory 14d caches a series of data (for example, the entire data of the Web page HP to be accessed) that is continuous with the drawing data G with the generation of the drawing data G for the client frame buffer RAM 14a. As a data CD, a flag indicating the data size (width × height), URL-ID, cache ID, and transfer priority level (Level-1 or 2 or 3) in the unit of screen scroll width Ds. The data compression method (0: JPEG or 1: PNG or...) Is added and stored.

  As described above, the cache state management buffer 14e stores state information (data-specific hash value / cache ID / 0: not yet specified) for each cache data in the screen scroll width Ds stored in the prefetch cache FIFO memory 14d. Send or 1: sent) Jds is stored.

  In the prefetch cache memory 14X, the entire data of the page HP associated with the URL of the Web page HP to be accessed is stored as cache data CD. In the cache status management buffer 14e, status information Jds about the cache data CD is stored for each URL of the Web page HP to be accessed.

  That is, when the determination level of the timing for transferring the cache data CD set in the cache transmission timing level memory 14f is [Level-1] (immediately after starting the loading of the Web page), the prefetch cache FIFO memory 14d has the first The cache data to which the flag [Level-1] indicating the priority transfer level is added is transferred to the client device 20, and when it is [Level-2] (immediately after loading the Web page), the second priority transfer is performed. The cache data to which the flag [Level-2] indicating the level is added is transferred, and [Level-3] (a certain time or more has elapsed from the input event from the client device 20 and is notified from the RTT measurement module 13a1) The measurement result of the transmission delay is less than the threshold and the drawing data G in the screen transmission FIFO memory 14c When the transfer waiting number Booking Ant device 20 is equal to or smaller than the threshold), the cache data where the flag indicating a transfer level of the third priority [Level-3] is added is transferred.

  When the Web page HP is stored in the prefetch cache memory 14X as cache data CD, the cache status information associated with the URL of the Web page HP is already stored in the cache status management buffer 14e. Only the page data in the scroll width Ds unit corresponding to the state information Jds where the hash values are different is rewritten and stored.

  Further, when the drawing data G generated in response to the input event from the client device 20 is transferred to the client device 20, the drawing data G to be transferred is the same as the hash value and the transmission data is “1”. For the portion where the cache data CD (in units of Ds) associated with the state information Jds exists, only the cache ID is transmitted to the client device 20, and the actual data is transmitted for the other portion.

  Next, the operation of the SBC system configured as described above will be described.

  FIG. 14 is a flowchart showing an overview of the cache acquisition transmission process and the scroll compatible transmission process executed by the server device 10 of the SBC system.

  FIG. 15 is a flowchart showing detailed processing of acquisition (b) and management / transmission (c) of the cache data CD included in the cache acquisition / transmission processing of the server device 10.

  FIG. 16 is a flowchart showing detailed processing of steps c2 to c4 in FIG.

  When the input event from the client device 20 is an access request to the Web page HP, an application program (Web browser program) corresponding to the input event stored in the program memory 13a is started and the requested Web site Is loaded (step a).

  Then, data corresponding to the display screen size of the client device 20 from the top of the loaded Web page HP is generated as drawing data G on the client frame buffer RAM 14a (see FIG. 7). At the same time, the entire data of the Web page HP received according to the transmission format Fhp shown in FIG. 8 is acquired as the cache data CD (step b).

  At this time, the drawing data G generated on the client frame buffer RAM 14a is written in the screen transmission FIFO memory 14c in units of the scroll width Ds (see FIG. 11C), and is sent to the event input source client device 20. Sent sequentially.

  The entire data (cache data CD) of the web page HP acquired from the web browser is first divided in units of scroll width Ds (see FIG. 7) (step c1).

  For the cache data CD divided in units of the scroll width Ds, a hash value corresponding to the content of the data is calculated (step c21), initialized to an untransmitted “0” state (step c22), and the cache ID is set. Issued (step c23).

  Then, it is determined whether or not a data area associated with the URL of the Web page HP (cache data CD) acquired from the Web browser has already been created in the cache state management buffer 14e (see FIG. 13) ( Step c31).

  Here, when the input event from the client device 20 is a request to access a new Web site, the cache status management buffer 14e associates the URL with the URL of the Web page HP (cache data CD) acquired this time. If it is determined that the management buffer data area has not been created (step c31 (NO)), as shown in FIG. 13, the management buffer data area associated with the URL is created (step c32). ).

  Then, state information (hash value / cache ID / transmission state: 0) for each cache data in the scroll width Ds obtained in steps c21 to c23 with respect to the data area of the created management buffer (14e). Jds is stored, and the cache data in units of the scroll width Ds is stored in the prefetch cache FIFO memory 14d as shown in FIG. 12 (step c4).

  On the other hand, if it is determined in the cache state management buffer 14e that the data area associated with the URL of the Web page HP (cache data CD) acquired this time has already been created (step c31 (YES)). Based on the state information Jds stored in the data area of the management buffer, cache data in units of the scroll width Ds having the same hash value is determined (step c33).

  Here, the cache data in units of the scroll width Ds determined to have the same hash value is not written into the cache state management buffer 14e and the prefetch cache FIFO memory 14d, including the state information Jds (step c33). (YES)). Only for the cache data in units of scroll width Ds determined that the hash values are different, that is, the data contents have been updated (step c33 (NO)), the cache state management buffer 14e and the prefetch cache FIFO memory 14d are rewritten. Is stored (step c4).

  Accordingly, the prefetch cache FIFO in which the entire data of the Web page HP acquired in response to the input event (request to access the Web page HP) from the client device 20 is divided into the scroll width Ds as the cache data CD. In addition to being stored in the memory 14d (see FIG. 12), state information (hash value / cache ID / transmission state) Jds of each cache data in units of the scroll width Ds is stored in the cache state management buffer 14e.

  FIG. 17 is a flowchart showing an input event recording process and a cache transmission timing [Level-3] determination process executed by the server device 10 of the SBC system.

  The input event recording process and the cache transmission timing [Level-3] determination process in the server device 10 are always activated and executed.

  In the input event recording process shown in FIG. 17A, every time an input event corresponding to the key operation or mouse operation is received from the client device 20 (step R1), the serial number and time stamp of the input event are obtained. The associated event is recorded in the input event time stamp memory 14g (step R2).

  In the cache transmission timing [Level-3] determination process shown in FIG. 17B, for example, when a timer handler that times up every n seconds is started (step S1), the current time stamp is acquired (step S2). Whether or not a certain period of time or more has elapsed from the time stamp of the latest input event recorded in the input event time stamp memory 14g, that is, not only has there been an input event from the client device 20, but also the server device 10 It is determined whether or not the load on the side is not heavy (step S3).

  If it is determined that the current time stamp has passed a certain period of time from the time stamp of the latest input event (step S3 (YES)), then the client device 20 stored in the RTT memory 14b is contacted. Transmission delay time t is acquired (step S4), and it is determined whether or not the transmission delay time t is equal to or less than a threshold value, that is, whether or not the communication state with respect to the client device 20 is good (step S5). .

  Here, if it is determined that the transmission delay time t with the client device 20 is equal to or less than the threshold value (step S5 (YES)), the screen transmission FIFO memory 14c (see FIG. 11C) does not transfer. The screen transfer reservation number of the client drawing data G in units of the scroll width Ds stored in step S6 is acquired (step S6), and is generated according to whether the screen transfer reservation number is equal to or less than a threshold value, that is, according to the input event. It is determined whether the waiting state for waiting to transfer the client drawing data G to the client device 20 is small (step S7).

  When it is determined that the screen transfer reservation number of the drawing data for client G is equal to or less than the threshold (step S7 (YES)), the current cache transmission timing is determined to be the third priority transfer level [Level-3]. The transfer level [Level-3] is stored in the cache transmission timing level memory 14f (step S8).

  Then, the timer is set, and the timer handler is again activated for standby (step S9 → S1).

  On the other hand, the current time stamp does not elapse for a certain period from the time stamp of the latest input event, that is, there is an input event from the client device 20 and the load on the server device 10 is heavy. Is determined (step S3 (NO)) or the transmission delay time t with the client device 20 is not less than the threshold value, that is, it is determined that the communication state with respect to the client device 20 is not in a good state. In this case (step S5 (NO)), or the screen transfer reservation number of the client drawing data G stored untransferred in the screen transmission FIFO memory 14c is not less than the threshold value, that is, the client device 20 of the client drawing data G When it is determined that there is not a small waiting state for transfer to (step S7 (NO)), The timer is set without being determined as the transfer level [Level-3], and again enters a standby state for starting the timer handler (step S9 → S1).

  FIG. 18 is a flowchart showing cache data acquisition processing executed in accordance with the flowcharts of FIGS. 15 and 16 and cache data transmission processing executed subsequent to the storage processing in the prefetch cache FIFO memory 14d.

  FIG. 19 is a diagram showing a cache data transmission format Tds accompanying the cache data transmission processing in FIG.

  When storage of cache data (for example, Web page HP data divided in units of scroll width Ds) is confirmed in the prefetch cache FIFO memory 14d (see FIG. 12) (step c5), the stored scroll width Ds. For the cache data in units, whether a flag (Level-1 or 2 or 3) indicating the level of transfer priority is read and matches the current transmission timing level stored in the cache transmission timing level memory 14f. It is determined whether or not (step c6).

  When it is determined that the flag (Level-1 or 2 or 3) indicating the level of transfer priority of the cache data confirmed in the prefetch cache FIFO memory 14d matches the current transmission timing level (step c6 (YES) )), The cache data is compressed according to a preset compression method (step c7) and transmitted to the event input source client device 20 in the transmission format Tds as shown in FIG. 19 (step c8).

  Then, the untransmitted / transmitted state information stored in the cache state management buffer 14e (see FIG. 13) in association with the cache data transmitted to the client device 20 has been transmitted from the untransmitted “0”. It is rewritten to “1” (step c9).

  That is, for the cache data CD (the entire data of the Web page HP) (see FIG. 7 and FIG. 10) stored in the pre-read cache FIFO memory 14d by being divided in units of the scroll width Ds (see the Web page) When the [Level-1] timing level is set in the cache transmission timing level memory 14f immediately after the start of HP loading), the first priority is most likely to scroll the screen immediately below the drawing data G for client display. Cache data of the area [Ds × n] set to the transfer level [Level-1] is transmitted.

  Further, when the timing level [Level-2] is set in the cache transmission timing level memory 14f immediately after the end of the acquisition of the cache data (immediately after the end of the loading of the Web page HP), the next highest possibility of screen scrolling. Cache data of the area [Ds × m] set to the 2-priority transfer level [Level-2] is transmitted.

  Furthermore, the measurement result of the transmission delay notified from the RTT measurement module 13a1 after a certain time has elapsed from the input event from the client device 20 is less than the threshold value, and the drawing data G in the screen transmission FIFO memory 14c is sent to the client device 20. When it is determined that the number of transfer waiting reservations (in units of Ds) is less than or equal to the threshold value and the load on the server device 10 is light, the timing level [Level-3] is set in the cache transmission timing level memory 14f. The cache data of the area corresponding to the drawing data G and the area up to the lower end of the Web page HP set at the third priority transfer level [Level-3] is transmitted.

  As a result, the application program (Web browser) corresponding to the input event (request for access to the Web page HP) from the client device 20 is activated, and the data of the Web page HP loaded from the Web site (URL) desired by the user is displayed. Based on this, drawing data G for client display is generated and transferred to the client device 20. At the same time, the entire data of the Web page HP is acquired as the cache data CD, and the cache data CD (see FIGS. 7 and 10) is the area most likely to be the screen scroll destination immediately below the drawing data G. [Ds × n] is set to the first priority transfer level [Level-1], and is transmitted to the client device 20 at a timing immediately after the start of loading the Web page HP. In addition, the area [Ds × m] up to the lower end of the Web page HP that has the next highest possibility of being the screen scroll destination is set to the second priority transfer level [Level-2], and immediately after the loading of the Web page HP is completed. It is transmitted to the client device 20 at timing. Then, the remaining untransmitted area of the Web page HP is set to the third priority transfer level [Level-3], and is transmitted to the client apparatus 20 at a timing when the load of the server apparatus 10 is light.

  For this reason, the cache data CD acquired by the server device 10 is stored at the optimal timing for the client device 20 to scroll the screen of the drawing data G and not delay the response process for the client device 20. Transmitted to the device 20.

  FIG. 20 is a flowchart showing details of the scroll-compatible transmission processing executed by the server device 10 of FIG.

  When a screen scroll request based on the drawing data G currently being displayed is received as an input event from the client device 20, for example, a display area to be scrolled according to the input time and the number of input of the cursor key signal is displayed. , Based on “x coordinate of base point”, “y coordinate of base point”, “width of display area”, “height of display area”, and “pixel value of scroll” included in transmission format Fhp of Web page HP shown in FIG. And is calculated in units of scroll width Ds (step d1).

  Then, based on the drawing data G generated on the client frame buffer RAM 14a in response to the screen scroll request, a new screen transfer area (data area updated by scrolling) stored in the screen transmission FIFO memory 14c is created. It is confirmed (step d2), and it is determined whether or not a data portion corresponding to the calculated scroll display area is included (step d3).

  When it is determined that the data portion corresponding to the calculated scroll display area is included in the new screen transfer area stored in the screen transmission FIFO memory 14c in response to the screen scroll request. (Step d3 (YES)), the hash value of the data portion (in units of scroll width Ds) corresponding to the scroll display area of the screen transfer area is calculated (step e1).

  In the cache state management buffer 14e (see FIG. 13), it is determined whether or not the state information Jds having the same hash value as the calculated hash value exists (step e2). Step e2 (YES)), it is determined whether or not the transmission state of the cache data associated with the state information Jds having the same hash value is [transmitted: 1] (step e3).

  Here, the transmission state of the cache data associated with the state information Jds having the same hash value as the hash value of the data portion (scroll width Ds unit) of the screen transfer area corresponding to the scroll display area is [Sent: 1 ] (Step e3 (YES)), the area on the display screen (position of the scroll width Ds) corresponding to the scroll display area stored in the screen transmission FIFO memory 14c (position) ) Only the information and the cache ID included in the cache data status information Jds are transmitted to the client device 20 that is the screen scroll request source (step f1).

  Then, the data portion (scroll width Ds unit) corresponding to the current scroll display area is removed from the screen transmission FIFO memory 14c, and the transfer to the client device 20 is omitted (step f2).

  As a result, even if there is an input event requesting screen scrolling from the client device 20, if the data portion of the drawing data G corresponding to the scroll display area and the cache data having the same hash value have been transmitted, By transmitting only the cache ID of the cache data as a response to the client device 20, transmission of the actual data portion corresponding to the scroll display area of the drawing data G can be omitted.

  On the other hand, the hash value of the data portion (scroll width Ds unit) corresponding to the scroll display area of the new screen transfer area stored in the screen transmission FIFO memory 14c is the same as that in the cache state management buffer 14e (see FIG. 13). When it is determined that the state information Jds having the hash value does not exist (step e2 (NO)), the data portion corresponding to the scroll display area becomes new data that does not exist as cache data. The data portion corresponding to the scroll display area of the new screen transfer area stored in the FIFO memory 14c is transferred to the client device 20 as usual (step g1).

  Further, the transmission state of the cache data associated with the state information Jds having the same hash value as the hash value of the data portion (scroll width Ds unit) of the screen transfer region corresponding to the scroll display region is [untransmitted: 0]. Even if it is determined that the data is stored (step e3 (NO)), the data portion corresponding to the scroll display area of the new screen transfer area stored in the screen transmission FIFO memory 14c is transferred to the client device 20 as usual. (Step g1).

  In this case, transmission of the cache data CD from the prefetch cache FIFO memory 14d in units of the scroll width Ds is not in time for the input event that requires scrolling (reason: transmission event is large, input event is large The cache data of the corresponding data portion stored in the prefetch cache FIFO memory 14d is turned to the end of the entire cache data and the transmission order is changed (step e4).

  FIG. 21 is a diagram showing the contents of the cache data stored in the prefetch cache memory 24a of the client device 20 of the SBC system.

  In the prefetch cache memory 24a of the client device 20, cache data CD (for example, an access target) transmitted from the server device 10 according to the cache acquisition transmission processing (see FIGS. 14A, 15, 16, and 18). The entire data of the Web page HP) is received in units of screen scroll width Ds, and together with the compressed data body, URL-ID, cache ID, data size (width × height), data compression method (0: JPEG) or 1: PNG or ...) is added and stored.

  FIG. 22 is a flowchart showing display processing of the client device 22.

  When an input event (for example, an access request for a Web page HP) corresponding to a user operation is generated in the client device 20 and transmitted to the server device 10, the application program (Web browser program) of the server device 10 responds to the input event. Then, the drawing data G generated according to the display screen size of the client device 20 (drawing data for the display screen size from the top of the Web page HP) is received (step h1).

  At this time, since it is determined that the drawing data G received from the server device 10 is not a cache ID (step h2 (NO)), the drawing data G is taken in (step h3b), and the compression is decoded. Are written in the frame buffer RAM 25 (step h4) and displayed on the display device 26 (step h5).

  Accordingly, the cache data CD (the entire data of the access target web page HP) transmitted from the server device 10 in accordance with the cache acquisition / transmission process is received, and as shown in FIG. 21, the screen scroll width Ds. Stored in the prefetch cache memory 24a in units.

  Here, when a screen scroll input event corresponding to a user operation is generated and transmitted to the server device 10, the scroll display is transmitted according to the scroll compatible transmission process (see FIG. 20) of the server device 10 in response thereto. The cache ID of the drawing data portion (scroll width Ds unit) corresponding to the area or the actual data of the drawing data portion is received (step h1).

  When it is determined that the cache ID has been received from the server device 10 (step h2 (YES)), the drawing data portion in units of the scroll width Ds having the cache ID is read from the prefetch cache memory 24a ( In step h3a), the compression is decoded and overwritten in the frame buffer RAM 25 (step h4) and displayed on the display device 26 (step h5).

  On the other hand, when it is determined that the actual data of the drawing data portion corresponding to the scroll display area has been received from the server device 10 (step h2 (NO)), the drawing data portion is fetched (step h3b). The compressed data is decoded and overwritten in the frame buffer RAM 25 (step h4) and displayed on the display device 26 (step h5).

  Therefore, according to the SBC system configured as described above, when the server device 10 receives an input event (Web page HP access request) from the client device 20, the server device 10 uses the application program ( The Web page HP is loaded and the Web page HP is loaded, and drawing data G matching the display screen size of the client device 20 is generated and transferred to the client device 20. The entire data of the Web page HP is stored in the prefetch cache memory 14X as cache data CD to which the cache ID is added after being divided by the scroll width Ds. The cache data in units of scroll width Ds stored in the prefetch cache memory 14X is immediately after the start of loading of the Web page HP sequentially from an area that is likely to be a screen scroll destination based on the drawing data G. The data is transmitted to the client device 20 at a three-stage timing immediately after the end of loading and when the server load is light, and stored in the prefetch cache memory 24a of the client device 20. When the server device 10 receives the screen scroll input event from the client device 20, the server device 10 generates drawing data G corresponding to the screen scroll, and cache data having the same hash value as that of the new drawing data portion corresponding to the scroll area. If there is, the information on the display position and only the cache ID are transmitted to the client device 20. The client device 20 reads the cache data in units of the scroll width Ds corresponding to the cache ID received from the server device 10 from the prefetch cache memory 24a, and executes scrolling of the display screen.

  For this reason, the server device 10 can transmit long data such as the web page HP as cache data for screen scrolling at an optimal timing that does not affect the main processing for the client device 20. The client device 20 can perform screen scrolling of long data such as the Web page HP with a good response even when the communication environment with the server device 10 is in a highly delayed state.

  Note that each processing method by the SBC system described in the above embodiment, that is, cache acquisition transmission processing by the server apparatus 10 shown in the flowcharts of FIGS. 14A, 15, 16, and 18, FIG. The input event recording process by the server apparatus 10 shown in the flowchart of FIG. 17, the cache transmission timing [Level-3] determination process by the server apparatus 10 shown in the flowchart of FIG. 17B, and the scroll corresponding transmission by the server apparatus 10 shown in the flowchart of FIG. Each method such as processing and client display processing shown in the flowchart of FIG. 22 is a program that can be executed by a computer, such as a memory card (ROM card, RAM card, etc.), magnetic disk (floppy disk, hard disk, etc.), Optical disc (CD-ROM DVD, etc.), can be distributed and stored in the medium of the external storage apparatus 18 and 28 such as a semiconductor memory. Then, the computers (CPUs 11 and 21) of the server device 10 and the client device 20 read the programs stored in the media of the external storage devices 18 and 28 into the storage devices (flash ROMs 13 and 23 and RAMs 14 and 24). By controlling the operation by the program, it is possible to realize the cache acquisition / transmission function of long data such as the Web page HP in the server apparatus 10 described in the embodiment, and execute the same processing by the above-described method. it can.

  Further, program data for realizing each of the above methods can be transmitted on the communication network (N) in the form of a program code, and from a computer device (program server) connected to the communication network (N). The program data can be fetched and stored in a storage device (flash ROMs 13 and 23 and RAMs 14 and 24), and the cache acquisition and transmission function of long data such as the Web page HP in the server device 10 can be realized.

  Note that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention at the stage of implementation. Further, each of the embodiments includes inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent elements are deleted from all the constituent elements shown in each embodiment or some constituent elements are combined in different forms, the problems described in the column of the problem to be solved by the invention If the effects described in the column “Effects of the Invention” can be obtained, a configuration in which these constituent requirements are deleted or combined can be extracted as an invention.

DESCRIPTION OF SYMBOLS 10 ... Server apparatus 20 ... Client apparatus 11, 21 ... CPU
12, 22 ... Bus 13, 23 ... ROM
13a, 23a ... Program memory 13a1 ... RTT measurement module 13a2 ... Screen control module 13a3, 23a1 ... Communication module 23a2 ... Input module 23a3 ... Screen display module 14, 24 ... RAM
14X, 24a ... prefetch cache memory 14a ... client frame buffer RAM
14b ... RTT memory 14c ... Screen transmission FIFO memory 14d ... Prefetch cache FIFO memory 14e ... Cache state management buffer 14f ... Cache transmission timing level memory 14g ... Input event time stamp memory 15, 25 ... Frame buffer RAM
16, 26 ... Display device 17, 27 ... Input device 18, 28 ... External storage device 19, 29 ... Communication I / F
N ... Communication network G ... Drawing data for client display HP ... Web page CD ... Cache data Ds ... Scroll width (movement amount)
Fhp: Web page transmission format Fhpe: Web page end format Jds: Cache data status information Tds: Cache transmission format

Claims (6)

Data storage means for dividing the data and storing it as divided data;
Rank setting means for setting the rank for each of the divided data stored by the data storage means;
Transmission timing determination means for determining the timing of transmitting the divided data according to the operation state of the own device;
Data transmission means for transmitting the divided data stored in the data storage means to the terminal device in accordance with the rank set by the rank setting means at the timing of data transmission determined by the transmission timing determination means;
A data transmission device comprising: The data storage means divides the data by a preset scroll unit and stores it as divided data.
The data transmission device according to claim 1. The transmission timing determining means determines a timing based on a transmission delay time;
The data transmission device according to claim 1, wherein the data transmission device is a data transmission device.   The transmission timing determining means determines immediately after the start of data acquisition, immediately after the end of acquisition of the data, and after a predetermined time has elapsed from the scroll input event for the data from the terminal device as the timing of transmitting the data. The data transmission device according to any one of claims 1 to 3.   The data transmission device according to any one of claims 1 to 4, wherein the data is data of a Web page. A program for controlling a computer,
Data storage means for dividing the data and storing it as divided data;
Rank setting means for setting the rank for each of the divided data stored by the data storage means;
Transmission timing determining means for determining the timing of transmitting data according to the operation state of the device;
At the data transmission timing determined by the transmission timing determination means, the divided data stored by the data storage means is made to function as a data transmission means for transmitting to the terminal device according to the order set by the order setting means. program.

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