JP4395776B2 - Communication method - Google Patents

Description

The present invention, method, etc. about the direction of data communication.

  A technology in which a plurality of information processing devices (nodes) such as personal computers are connected by a communication line to form a network and these information processing devices communicate with each other is widely spread. As communication technology, methods as described in Patent Documents 1 to 3 have been proposed.

  According to the method described in Patent Document 1, each terminal device in the network holds a group public key formed in the network. In this network, when a terminal device makes an inquiry to another terminal device as to whether or not the other terminal device is a member of the group, the other terminal device responds to the inquiry as follows: Send predetermined encrypted data. The terminal device that has made the inquiry confirms that the other terminal device is a member of the group by decrypting the encrypted data with the group public key.

  According to the method described in Patent Document 2, when a process of dividing a query process of one node into a first node group and a query process time limit Qt are given, it is necessary to finish the process within Qt. The process of determining the number of nodes P and the processing request relationship for equalizing the processing load of the first node group when requesting the database processing from the first node group to the second node group accessing the actual database. When there is an imbalance in the processing load of the first node group in the process of determining and the above processing request relationship, the processing load of the first node group is reduced by dividing the second node group into nodes. Furthermore, the process consists of a process of determining the processing request relationship to be balanced and a process of determining a response method in which the first node group returns the processing result returned from the second node group to the user.

According to the method described in Patent Document 3, in a process in which a certain host computer reserves a resource used for job execution with respect to a resource proxy connected via a network, the resource proxy issues a reservation request. Reservation process certificate issuance request is sent to the host computer. Then, the host computer confirms the reservation by returning a reservation process certificate to the resource proxy.
JP 2004-159298 A JP-A-6-309284 JP 2005-165568 A

  By the way, in general, communication may only transmit data from one node to the other node, or data for inquiry from one node to the other node (hereinafter referred to as “inquiry data”). In some cases, data indicating an answer to the inquiry data (hereinafter referred to as “answer data”) is transmitted from the other node to the one node.

  In the latter case, one node may receive response data from the other node after a long time has passed since the inquiry data was transmitted to the other node of the inquiry destination.

  The answer data obtained after such a long time may be wasted for the query source node. This is because the query source node may obtain necessary answer data from another node. Alternatively, the processing may be completed without waiting for the response data to be transmitted.

  In this case, useless answer data is exchanged between nodes, which increases the load on the network. In addition, both nodes perform useless communication processing, and use their own resources such as CPUs.

  However, the conventional methods as described in Patent Documents 1 to 3 cannot solve these problems.

  The present invention has been made in view of such a problem, and an object of the present invention is to reduce the load of a network constituted by a plurality of nodes and the processing load of each node as compared with the conventional art.

  Alternatively, a communication method in a network constituted by a plurality of terminal devices, wherein the first terminal device in the network is a first that indicates job execution inquiry data and an expiration date for making an inquiry regarding job execution. The expiration date data is associated with each other and transmitted to each second terminal device in the network, and each second terminal device corresponds to the job execution inquiry data from the first terminal device. When the expiration date indicated by the one expiration date data has not expired, the first terminal device associates the response data indicating the response regarding the job execution inquiry data with the second expiration date data indicating the expiration date The first terminal device responds to the response data from the second terminal device and the second validity period corresponding to the response data. Based on the data, it is determined which of the second terminal devices in the network the job is to be executed, and the first terminal device Job execution request data for requesting job execution is transmitted.

  According to the present invention, it is possible to reduce the load of a network constituted by a plurality of nodes and the processing load of each node as compared with the conventional art.

  1 is a diagram illustrating an example of the overall configuration of the network 1, FIG. 2 is a diagram illustrating an example of a hardware configuration of the terminal device 2, FIG. 3 is a diagram illustrating an example of a functional configuration of the terminal device 2, and FIG. FIG. 4 is a diagram illustrating an example of a logical topology of the terminal device 2.

  As shown in FIG. 1, a network 1 according to the present invention includes a LAN (Local Area Network) composed of nodes such as a plurality of terminal devices 2 (21, 22,..., 2n), a switching hub 3, and a router 4. ). These terminal devices 2 are connected to the switching hub 3 in a star shape by a twisted pair cable. The switching hub 3 and the router 4 are also connected by a twisted pair cable. Hereinafter, a case where the terminal devices 2 among these nodes perform data communication will be described.

  The terminal device 2 is a device that executes data input / output processing with another device such as a personal computer, a workstation, or a printer. Hereinafter, a case where a personal computer is used as the terminal device 2 will be described as an example.

  As shown in FIG. 2, the terminal device 2 includes a CPU 20a, a RAM 20b, a ROM 20c, a hard disk 20d, a communication interface 20e, an image interface 20f, an input interface 20g, and other various circuits or devices.

  The communication interface 20e is a NIC (Network Interface Card), and is connected to one of the ports of the switching hub 3 via a twisted pair cable. The image interface 20f is connected to a monitor and sends a video signal for displaying a screen to the monitor. The input interface 20g is connected to an input device such as a keyboard or a mouse, and signals indicating the operation contents of the user are input from these input devices.

  The hard disk 20d includes a data operation management unit 201, a data reception unit 202, an expiration date determination unit 203, a clock function unit 204, a data analysis unit 205, a job execution availability determination unit 206, and a job request destination determination unit as illustrated in FIG. 207, job reservation unit 208, connection table storage unit 209, connection table management unit 210, data storage unit 211, job start date calculation unit 212, system information acquisition unit 213, expiration date setting unit 214, transmission data generation unit 215, data A program and data for realizing the functions of the transmission unit 216, the command reception unit 217, and the like are stored. These programs and data are read into the RAM 20b as necessary, and the programs are executed by the CPU 20a. Some functions may be realized in hardware by a dedicated circuit or the like.

  Each terminal device 2 is given a host name (machine name), an IP address, and a MAC address for identification with other terminal devices 2. The host name can be freely assigned by the administrator of the network 1 or the like. The IP address is given according to the rules of the network 1. The MAC address is an address fixedly given to the communication interface 10e of the terminal device 2. In the present embodiment, it is assumed that a host name such as “PC1”, “PC2”,. Hereinafter, these terminal devices 2 may be described by host names.

  Further, these terminal devices 2 are virtually assumed to be arranged in a virtual space, as shown in FIG. And as shown with a dotted line, it is linked | related with the at least 1 other terminal device 2 of the vicinity in the virtual space. And by these associations, all the terminal devices 2 are directly or indirectly related to each other. Note that “directly related” means that they are connected by a single dotted line in FIG. 4 (for example, a relationship such as PC1, PC2, and PC9 in FIG. 4). “Yes” means that they are connected by two or more dotted lines and one or more nodes (for example, the relationship between PC1 and PC4 in FIG. 4). The terminal device 2 transmits data to other terminal devices 2 that are directly associated with the terminal device 2. Hereinafter, “associated” means directly associated unless otherwise specified.

  The terminal device 2 can request another terminal device 2 associated with the terminal device 2 to execute the job. For example, the terminal device 2 can request another terminal device 2 to execute a job that cannot be executed by the terminal device 2 because of its own specifications or current resource usage. Alternatively, there is a case where another terminal device 2 is requested to execute a job based on a user instruction.

  Here, the case where the PC 7 makes a job request to any of the other terminal devices 2 associated with the PC 7 (that is, one of the PC 2, PC 6, PC 8 and PC 9) will be described as an example. Briefly explain the flow and exchange of data.

  The PC 7 transmits inquiry data IR for requesting execution of the job to the PC 2, PC 6, PC 8, and PC 9. In this inquiry data IR, in addition to data indicating the contents of the job (job type and processing conditions, etc.), an inquiry as to whether or not the processing of the contents can be executed and when the job is executed The data of the inquiry about whether or not can be included.

  When PC2, PC6, PC8, and PC9 receive the inquiry data IR, each transmits an answer to the inquiry indicated by the inquiry data IR as answer data DTA to the inquiry source PC7.

  When the PC 7 receives the response data DTA from each terminal device 2, the PC 7 determines the terminal device 2 that requests the job based on the response data DTA, and data for requesting the execution of the job (hereinafter, “ Is transmitted to the terminal device 2 that has been determined.

  The terminal device 2 that has received the formal request data RQ transmits data indicating that the job execution request has been received (hereinafter referred to as “acceptance notification data AC”) to the PC 7. Then, after execution of the job is completed, data including the execution result and completion (hereinafter referred to as “job completion report data CP”) is transmitted to the requesting PC 7.

  5 is a diagram showing an example of the connection table TL of the terminal device 2 associated as shown in FIG. 4, FIG. 6 is a diagram showing an example of the job management table TJ of the PC 7, and FIG. 7 is a diagram of the requested job management table TI of the PC 7. FIG. 8 is a diagram showing an example, and FIG. 8 is a diagram showing an example of the answer management table TA of the PC 7. Hereinafter, the processing content of each part of the terminal device 2 shown in FIG. 3 is demonstrated in detail.

  The connection table storage unit 209 stores a connection table TL indicating a list of attributes such as host names, IP addresses, and MAC addresses of other terminal devices 2 associated with the terminal device 2 itself. For example, connection tables TL1, TL2, TL6, TL7, TL8, and TL9 as shown in FIG. 5 are stored in the connection table storage unit 209 of PC1, PC2, PC6, PC7, PC8, and PC9 in FIG. ing. The contents of these connection tables TL are created in advance by the administrator based on the association of each terminal device 2.

  The connection table management unit 210 manages connection destination information stored in the connection table storage unit 209.

  The data storage unit 211 includes data used by the OS or application software, data created by the user using application software, data relating to a job executed in the terminal device 2 (hereinafter referred to as “job data DTJ”), Data relating to a job requested to be executed by another terminal device 2 (hereinafter referred to as “request job data DTI”), response data DTA to the inquiry data IR transmitted to the other terminal device 2, and various other data, Saved as a file.

  Here, a job management table TJ for managing job data DTJ, a requested job management table TI for managing requested job data DTI, and an answer management table TA for managing answer data DTA will be described.

  In the job management table TJ, job data DTJ is stored for each job executed in the terminal device 2 as shown in FIG.

  The “job number” of the job data DTJ is a number assigned to identify a job. “Requester” indicates the host name of another terminal device 2 that has requested the job. However, if the job is not requested by another terminal device 2 but is generated by the terminal device 2 itself, the host name of the terminal device 2 itself is indicated.

  “Status” indicates the current processing status of the job. In this field, “being executed”, “waiting for processing”, “waiting for request notification”, or the like is indicated according to the state of the processing. “Executing” means that the job is currently being executed in the terminal device 2. “Waiting for processing” means that the job is waiting to be executed. The “waiting for processing” job is sequentially executed when the “under execution” job is completed. “Waiting for notification of request” means a state of waiting for a formal request for the job after answering an inquiry (executability / non-executable and startable time) regarding the job from another terminal device 2.

  The “expiration date” indicates how long an official request is to be waited for when the job is in the “waiting for request notification” state. This field is blank for job data DTJ of a job generated in the terminal device 2 itself. “Job type” indicates the type of the job. The job type includes file search or data processing.

  In the requested job management table TI, as shown in FIG. 7, requested job data DTI is stored for each job that the terminal device 2 has requested the other terminal device 2 to execute.

  The “request job number” of the request job data DTI is a number assigned to identify a job requested to be executed by another terminal device 2.

  “Status” indicates the current processing status for the job. In this field, “inquiry”, “waiting for reception notification”, “requested”, or the like is displayed according to the state of processing. “Inquiry” means that the response data DTA for the inquiry data IR is returned after the inquiry data IR for inquiring whether the job can be executed and when it can be started is sent to the other terminal devices 2. It means waiting. “Waiting for acceptance notification” means that after sending formal request data RQ for officially requesting execution of the job to the other terminal apparatus 2, acceptance notification data AC for the formal request data RQ is returned. Means waiting. “Requested” means that reception notification data AC has been received from another terminal device 2 for the job. That is, it means a state waiting for completion of execution request processing to the other terminal device 2 for the job and transmission of the execution result of the job from the other terminal device 2.

  The “expiration date” indicates the expiration date for the transmitted inquiry data IR or formal request data RQ. That is, for the requested job data DTI whose “state” is “inquiry”, the time limit for replying to the transmitted inquiry data IR is shown. In addition, for request job data DTI whose “status” is “waiting for reception notification”, a time limit for receiving an answer as to whether or not the job request can be received is shown.

  “Job type” indicates the type of the job. The job type includes file search or data processing.

  In the answer management table TA, as shown in FIG. 8, answer data DTA received by the terminal apparatus 2 from other terminal apparatuses 2 is stored. The contents of the answer data DTA will be described later.

  The data receiving unit 202 receives packets necessary for the terminal device 2 among the packets flowing through the network 1.

  When the expiration date is associated with the data received by the data reception unit 202 (hereinafter referred to as “received data”), the expiration date determination unit 203 associates the expiration date with the current date and time (date and time). ) To determine whether the received data has not expired.

  The clock function unit 204 provides the current date and time to the expiration date determination unit 203 and the expiration date setting unit 214.

  The data analysis unit 205 determines the type of the received data by extracting necessary information from the received data and analyzing the contents. That is, it is determined whether the received data is “inquiry data”, “answer data”, “formal request data”, “acceptance notification data”, “job completion report data”, or the like.

  The data operation management unit 201 is configured to execute a job management table TJ, a requested job based on a request from the data analysis unit 205, job execution availability determination unit 206, job reservation unit 208, expiration date setting unit 214, command reception unit 217, or the like. Processing related to data in the management table TI or the answer management table TA is performed.

  For example, the job data DTJ is newly registered in the job management table TJ, the request job data DTI is newly registered in the request job management table TI, or the answer data DTA is newly registered in the answer management table TA. In addition, a process of updating the contents of these data, a process of deleting unnecessary data from the tables, a process of searching the requested data from these tables and giving them to the requester, and the like are performed.

  In addition, the job management table TJ and the requested job management table TI are constantly monitored or periodically checked to detect the job data DTJ or the requested job data DTI having expired.

  When the received data is determined to be the inquiry data IR by the data analysis unit 205, the job execution possibility determination unit 206 and the job start date / time calculation unit 212 perform a process for issuing an answer to the inquiry data IR. That is, the job execution possibility determination unit 206 determines whether or not the job having the content indicated by the inquiry data IR can be executed. When it is determined that the job can be executed, the job start date and time calculation unit 212 calculates when the job can be started, that is, the start date and time of the job.

  The job request destination determination unit 207 performs processing for determining the terminal device 2 (request destination) from which a job is officially requested.

  The job reservation unit 208 receives a formal request for a job from another terminal device 2 and performs processing for reservation of the job.

  The system information acquisition unit 213 relates to specifications such as the clock frequency and data processing unit of the CPU 20a of the terminal device 2 itself, the capacity of the RAM 20b, the capacity of the hard disk 20d, the type of installed software and hardware, and the functions that can be realized. Get information. Also, information on the current usage status of these resources is acquired. Hereinafter, the acquired information is referred to as “system information SI”.

  The expiration date setting unit 214 sets an expiration date in the data transmitted to the other terminal device 2 as necessary.

  The transmission data generation unit 215 transmits data to be transmitted to another terminal device 2 (hereinafter referred to as “transmission data”) based on instructions from the job execution possibility determination unit 206, job request destination determination unit 207, job reservation unit 208, and the like. ”).

  The data transmission unit 216 packetizes transmission data generated by the transmission data generation unit 215 and transmits the packetized data to another terminal device 2.

  The command receiving unit 217 receives a command designated by the user by operating a keyboard or a mouse, and causes each unit to execute processing corresponding to the command.

  In addition, the terminal device 2 has a function of applying to the other terminal device 2 to perform node authentication or user authentication of the terminal device 2 itself and performing a process for participating in the network 1, in order to leave the network 1. And a function of performing node authentication or user authentication of the other terminal device 2 based on an application from another terminal device.

  9 and 10 are flowcharts for explaining an example of the processing flow of each terminal device 2 when the PC 7 makes a job execution request to any one of the terminal devices 2 associated with the PC 7.

  Next, the processing content of each unit in FIG. 3 will be described in more detail with reference to the flowcharts in FIGS. 9 and 10, taking as an example the case where the PC 7 requests a job from another terminal device 2. Note that the control for the processing of FIGS. 9, 10 and the flowchart is performed by the CPU 20a.

  The user operates the keyboard of the PC 7 and gives a command to cause the other terminal device 2 to execute the job. At this time, the user designates the job type, processing conditions, and the like. Then, in the PC 7, the command reception unit 217 receives these commands and processing conditions, and requests the data operation management unit 201 to start processing for causing the other terminal devices 2 to execute the job. (# 7-1 in FIG. 9).

  When the data operation management unit 201 receives the request from the command reception unit 217, the data operation management unit 201 issues a unique job number to the job, and sends the inquiry data IR for the job to the transmission data generation unit 215. Instruct. In the example of FIG. 9, it is assumed that “0003” is issued as the job number.

  Then, the transmission data generation unit 215 generates inquiry data IR (# 7-2). In the inquiry data IR, a message requesting a reply indicating whether or not the job type and processing conditions designated by the user, the job number issued by the data operation management unit 201, and the job can be executed. , And a message requesting an answer about when the job can be executed. Furthermore, the expiration date setting unit 214 is caused to execute a process for setting a response time limit for these inquiries, and the time limit is adopted as the time limit for the inquiry data IR (# 7-3). Specifically, data indicating the time limit set by the expiration date setting unit 214 is included in the inquiry data IR. The expiration date may be determined by adding a predetermined time to the current date and time notified from the clock function unit 204, for example. Alternatively, the user may be able to specify for each job.

  In parallel with or before or after the process of generating the inquiry data IR, the data operation management unit 201 newly generates requested job data DTI for the job and registers it in the requested job management table TI (# 7). -4). The contents of the requested job data DTI are as described above. At this time, the “status” of the requested job data DTI is set to “inquiry”. In addition, “request job number”, “expiration date”, and “job type” are specified by the job number issued by the data operation management unit 201, the time limit set by the expiration date setting unit 214, and the user, respectively. Stores information indicating the type of job performed.

  The data transmission unit 216 transmits the generated inquiry data IR to PC2, PC6, PC8, and PC9 associated with the PC7 itself based on the connection table TL7 of the PC7 itself (# 7-5). .

  In PC2, PC6, PC8, and PC9, each data receiving unit 202 receives inquiry data IR transmitted from PC7 (# 2-1, # 6-1, # 8-1, # 9- 1). The expiration date determination unit 203 determines whether the query data IR has not expired by comparing the date indicated in the query data IR with the current date and time (# 2-2, # 6-2, # 8-2, # 9-2).

  If the current date has passed the time limit indicated in the inquiry data IR, it is determined that the inquiry data IR has expired. In this case, the inquiry data IR is discarded. On the other hand, if the current date has not yet passed the deadline indicated in the inquiry data IR, it is determined that the inquiry data IR has not yet expired. In this case, the continuation of the flowchart is continued.

  However, in the example of FIG. 9, it is determined that the expiration date is determined not to have expired in PC2, PC6, and PC8, and has been determined to have expired in PC9. Therefore, only the PC 9 discards the inquiry data IR here and ends the processing.

  The data analysis unit 205 determines the type of data by analyzing the inquiry data IR received by the data reception unit 202. Here, it is naturally determined that it is “inquiry data”. If it is determined that the query data is “inquiry data”, the data analysis unit 205 determines whether or not the job related to the query data IR can be executed by the terminal device 2 itself. To request.

  Then, the job execution possibility determination unit 206 causes the system information acquisition unit 213 to acquire system information SI indicating the specifications of the terminal device 2 itself and the current resource status. Then, based on the system information SI, it is checked whether or not the terminal device 2 itself has a specification for executing a job of the type and processing content indicated in the inquiry data IR. If it is provided, it is determined that the job related to the inquiry data IR can be executed. If it is not provided, it is determined that the job cannot be executed (# 2-3, # 6-3, # 8-3). ).

  If it is determined that the job related to the inquiry data IR can be executed, the job start date calculation unit 212 calculates the time when the job can be started. The timing may be calculated in consideration of the specifications and resource status indicated in the system information SI of the terminal device 2 itself, as well as other jobs that are currently waiting for processing in the terminal device 2. Since the resource status of the terminal device 2 itself and the traffic on the communication line 3 constantly change, it is difficult to calculate an accurate value. Therefore, it is only necessary that the estimated value can be calculated.

  Through these processes, an answer to the query shown in the query data IR is obtained. That is, an answer about whether or not the job relating to the inquiry data IR can be executed and an answer about when the execution can be started are obtained.

  The transmission data generation unit 215 generates response data DTA indicating these responses and the job number for the job related to the inquiry data IR (# 2-4, # 6-4, # 8-4). However, in the example of FIG. 9, it is assumed that PC2 and PC6 have determined that the job can be executed, and that PC8 has determined that the job cannot be executed. Therefore, the PC 2 and the PC 6 generate the response data DTA indicating that the job can be executed, the time when the execution can be started, and the job number. On the other hand, the PC 8 generates response data DTA indicating that the job cannot be executed and the job number. In addition, PC2 and PC6 can start execution at "7:10:05 on Oct. 1, 2005" and "7:10:30 on Oct. 1, 2005, respectively." "It is possible to start at".

  Further, in the terminal device 2 that replies that it can be executed, that is, the PC 2 and the PC 6, the expiration date setting unit 214 executes a process for setting the time limit for accepting the formal request of the job, Corresponding as the expiration date of the data DTA (# 2-5, # 6-5). Specifically, data indicating the time limit set by the expiration date setting unit 214 is included in the response data DTA. For example, the expiration date may be determined by adding a predetermined time to the current date and time.

  In PC2 and PC6, the data operation management unit 201 newly generates job data DTJ for the job in parallel with or before and after the process of generating the response data DTA, and registers it in the job management table TJ (# 2-6, # 6-6 in FIG. At this time, the “status” of the job data DTJ is set to “wait for request notification”. The “job number”, “request source”, “expiration date”, and “job type” are set by the job number (that is, “0003”) and the expiration date setting unit 214 indicated in the inquiry data IR, respectively. Information indicating the type of job indicated in the inquiry period IR, the host name of the terminal device 2 that is the transmission source of the inquiry data IR (that is, “PC7”), and the inquiry data IR is stored.

  In PC2, PC6, and PC8, the data transmission unit 216 transmits the generated response data DTA to the PC 7 that is the transmission source of the inquiry data IR (# 2-7 in FIG. 9, # 6- in FIG. 10). 7, # 8-5).

  By the way, when the inquiry data IR of another job is newly transmitted between the time when the job data DTJ is registered in the job management table TJ and the time when the job data DTJ is discarded, the job execution possibility determination unit 206 determines that the job cannot be executed. This is to ensure execution of a job related to the registered job data DTJ (that is, a job that has been previously inquired). Therefore, registering the job data DTJ in the job management table TJ can be said to temporarily reserve a job. Hereinafter, registering the job data DTJ in the job management table TJ may be referred to as “provisional reservation”.

  In PC7, the data receiving unit 202 receives the answer data DTA transmitted from PC2, PC6, and PC8 (# 7-6 in FIG. 9, # 7-9, # 7-12 in FIG. 10). The expiration date determination unit 203 determines whether the response data DTA has not expired by comparing the expiration date indicated in the response data DTA with the current date and time (# 7-7, # 7 in FIG. 10). -10). In this example, as described above, no expiration date is set for the response data DTA transmitted from the PC 8. Therefore, this answer data DTA is not determined for expiration.

  If the current date and time has passed the time limit indicated in the response data DTA, it is determined that the response data DTA has expired. In this case, the answer data DTA is discarded. On the other hand, if the current date has not yet passed the deadline indicated in the answer data DTA, it is determined that the answer data DTA has not yet expired. In this case, the response data DTA is analyzed by the data analysis unit 205. Further, the response data DTA for which no expiration date is set is also analyzed by the data analysis unit 205.

  The data analysis unit 205 determines the type of data by analyzing the response data DTA received by the data reception unit 202. Here, it is naturally determined that the data is “answer data”. If the data analysis unit 205 determines that the response data is “response data”, the data analysis unit 205 requests the data operation management unit 201 to register the content indicated in the response data DTA in the response management table TA.

  The data operation management unit 201 registers the response data DTA in the response management table TA based on a request from the data analysis unit 205 (# 7-8, # 7-11, and # 7-13 in FIG. 10). Here, the answer management table TA will be described.

  In the answer management table TA of FIG. 8, “request job number” of the answer data DTA indicates the job number of the job related to the answer data DTA. The job number indicated by the “request job number” of the response data DTA is the same as the job number of the “request job number” of any request job data DTI in the request job management table TI. The response data DTA and requested job data DTI having the same job number are data relating to the same job.

  The “transmission source” indicates the host name of the terminal device 2 that has transmitted the response data DTA, that is, the terminal device 2 that is the respondent. “Message content” indicates the content of the response included in the response data DTA, that is, whether or not the job can be executed and the execution start time.

  In the example of FIG. 9, PC2, PC6, and PC8 returned response data DTA to the inquiry data IR whose job number is “0003”. Therefore, as shown in FIG. 8, three response data DTAs with “Request job number” “0003” are registered in the response management table TA. Then, the “transmission source” of the three response data DTA is “PC2”, “PC6”, or “PC8”, which is the host name of the terminal device 2 that has transmitted the data. The “message contents” correspond to the contents of the answers indicated in the answer data DTA. That is, “startable at 7: 3: 20 on October 1, 2005”, “startable at 7:10:30 on October 1, 2005”, or “job execution impossible”.

  When the response data DTA is returned from all of the terminal devices 2 that have transmitted the inquiry data IR, the data operation management unit 201 notifies the job request destination determination unit 207 to that effect. Each time the response data DTA is transmitted, the data operation management unit 201 stores the host name of the terminal device 2 registered in the connection table TL7 and the response data DTA corresponding to “request job number” in the response management table TA. Check the "host name" displayed. As a result, it is possible to detect whether or not the answer data DTA has been received from all of the terminal devices 2 to which the inquiry data IR has been transmitted.

  Further, the data operation management unit 201 constantly monitors or periodically checks the requested job management table TI, so that requested job data DTI (that is, “status”) of the job being inquired of another terminal device 2 is displayed. Among the requested job data “DTI” which is “inquiry”, the one whose response time limit has passed is detected. When such requested job data DTI is detected, the job request destination determination unit 207 is notified of this fact.

  The job request destination determination unit 207 has detected that the response data DTA has been received from all of the terminal devices 2 to which the inquiry data IR related to the job to be requested has been transmitted, or has detected the request job data DTI whose response has expired. Is received from the data operation management unit 201, the process for determining the request destination of the job is performed as follows (# 7-14).

  When the former notification is received, the answer data DTA having the earliest job startable time is selected, and the terminal device 2 that has sent the answer data DTA is determined as the request destination. When three answer data DTA are obtained for the job having the job number “0003” as shown in FIGS. 9 and 10, the PC 2 is determined as the request destination.

  On the other hand, when the latter notification is received, the job number having the same value as the request job number of the request job data DTI related to the notification is selected from the response data DTA registered in the response management table TA at that time. Answer data DTA is extracted. Then, as in the case of receiving the former notification, the extracted response data DTA having the earliest job startable time is selected, and the terminal device 2 that has sent the response data DTA is selected as the request destination. decide.

  If no reply data DTA related to the job that you want to request has been received by this time, execute the job yourself or send the inquiry data IR related to the job again. Perform proper processing.

  The transmission data generation unit 215 generates formal request data RQ for officially requesting execution of the job to the PC 2 that is the requested terminal device 2 determined by the job request destination determination unit 207 (# 7-15). The formal request data RQ includes a job number of the job, a formal request message, and the like. Then, the expiration date setting unit 214 executes a process for setting a response time limit for the request, and sets the time limit as the time limit for the formal request data RQ (# 7-16). Specifically, data indicating the time limit set by the expiration date setting unit 214 is included in the formal request data RQ. The expiration date may be determined by adding a predetermined time to the current date and time notified from the clock function unit 204, for example.

  Further, in parallel with or before or after the process of generating the formal request data RQ, the data operation management unit 201 determines the request job data DTI corresponding to the officially requested job in the request job management table TI. The “expiration date” is updated to the reply time limit set this time in the formal request data RQ, and the “status” is updated from “inquiry” to “waiting for reception notification”.

  The data transmission unit 216 transmits the generated formal request data RQ to the PC 2 (# 7-17).

  In the PC 2, the data receiving unit 202 receives the formal request data RQ transmitted from the PC 7 (# 2-8). The expiration date determination unit 203 determines whether the official request data RQ has not expired by comparing the time limit indicated in the official request data RQ with the current date and time (# 2-9). If the current date and time has passed the time limit indicated in the inquiry data IR, it is determined that the formal request data RQ has expired. In this case, the official request data RQ is discarded. On the other hand, if the current date has not yet passed the deadline indicated in the formal request data RQ, it is determined that the formal request data RQ has not yet expired. In this case, the process after step # 2-10 is continued. In the example of FIG. 9, it is determined that the expiration date has not expired.

  The data analysis unit 205 determines the type of data by analyzing the formal request data RQ received by the data reception unit 202. Here, it is naturally determined that the data is “official request data”. If it is determined that the data is “official request data”, the data analysis unit 205 notifies the job reservation unit 208 that the official request data RQ has been received.

  Upon receiving the notification from the data analysis unit 205, the job reservation unit 208 generates a transmission data generation unit so as to generate reception notification data AC indicating that the job request of the job number indicated in the formal request data RQ has been officially received. 215 is instructed.

  Then, the transmission data generation unit 215 generates reception notification data AC (# 2-11). The reception notification data AC includes a job number of a job that has received a request, a message indicating that the request has been received, and the like.

  In parallel with or before or after the process of generating the reception notification data AC, the job reservation unit 208 reserves a job of the received formal request data RQ (# 2-10). That is, the “status” of the job data DTJ corresponding to the job in the job management table TJ is updated from “wait for request notification” to “wait for processing”. Thereby, the temporarily reserved job is formally reserved. After that, the job is executed when the turn comes around.

  The data transmission unit 216 transmits the generated reception notification data AC to the requesting PC 7 (# 2-12). Here, since it is not necessary to receive a response to the reception notification data AC from the PC 7, no expiration date is set.

  In the PC 7, the data receiving unit 202 receives the reception notification data AC from the PC 2 (# 7-18). Then, the data analysis unit 205 determines the type of data by analyzing the reception notification data AC. Here, it is determined that the data is “acceptance notification data”. If the data analysis unit 205 determines that the data is “reception notification data”, the data analysis unit 205 requests the data operation management unit 201 to register that the job request related to the reception notification data AC has been received.

  The data operation management unit 201 performs registration processing in accordance with a request from the data analysis unit 205. Specifically, the “status” of the requested job data DTI of the job in the requested job management table TI is changed from “waiting for reception notification” to “requested”. As a result, the request destination of the job is determined.

  When the execution of the job requested by the PC 7 is completed in the PC 2 (# 2-13), the job completion report data CP including the job number and job execution result data of the job is generated by the transmission data generation unit 215. The data transmission unit 216 transmits the data to the PC 7 (# 2-14). In the PC 7, when the job completion report data CP is received by the data receiving unit 202, the requested job data DTI corresponding to the job related to the job completion report data CP is subjected to request job management through analysis processing by the data analysis unit 205. Delete from table TI.

  On the other hand, in the other terminal device 2 that returns the reply data DTA indicating that the job can be executed to the PC 7, that is, the PC 6, thereafter (after # 6-7), the following processing is performed. Done.

  The data operation management unit 201 always or periodically checks whether the current date and time has passed the expiration date of the job data DTJ of the job (# 6-8). If the formal request data RQ for the job does not come from the PC 7 even after the expiration date, it is assumed that the formal request for the job has been made to another terminal device 2, and the job data DTJ is managed by the job. Delete from the table TJ (# 6-9). That is, the temporary reservation of the job is canceled.

  When the official request destination of the job is determined by the request source (here, PC 7), the terminal device 2 (here, PC 6) not selected as the request destination is notified of that fact. You may comprise. When the notification is received, the job data DTJ of the job may be deleted without waiting for the expiration date.

  Further, due to an increase in the load on the communication line or the occurrence of an abnormality such as a failure of the official request destination of the job (here, PC2), the job reception notification data AC is sent to the request source (here, PC7). In some cases, the request is not transmitted by the expiration date indicated in the requested job data DTI. In such a case, it is conceivable to cope with the following method.

  One method is a method for coping with the formal request data RQ by retransmitting it to the PC 2. Alternatively, the job may be executed by the PC 7 itself. Alternatively, the terminal device 2 other than the PC 2 may be selected again from the terminal devices 2 that have answered that the job can be executed, and the formal request data RQ may be transmitted again. Which of these coping methods is adopted may be determined according to the situation at that time.

  As described above, the processing related to the job generated in the PC 7 is executed in each terminal device 2.

  FIG. 11 is a flowchart for explaining the flow of processing in the request source terminal apparatus 2X when the inquiry data IR is transmitted, and FIG. 12 explains the flow of processing in the request source terminal apparatus 2X after receiving the response data DTA. FIG. 13 is a flowchart for explaining the flow of processing in the related terminal device 2Y when transmitting the response data DTA, and FIG. 14 is for explaining the flow of processing in the related terminal device 2Y after provisional reservation. It is a flowchart.

  Next, the overall processing flow when a certain terminal device 2 requests a job from another terminal device 2 associated with the terminal device 2 will be described with reference to the flowcharts of FIGS. Hereinafter, in the description of the flowcharts of FIGS. 11 to 13, the terminal device 2 that performs the request is referred to as “request source terminal device 2X”, and the terminal device 2 associated with the request source terminal device 2X is referred to as “related terminal device 2Y”. ".

  Upon requesting a job, the request source terminal device 2X generates inquiry data IR relating to the job to be requested (# 10 in FIG. 11), sets an expiration date (# 11), and transmits it to each related terminal device 2Y. (# 12).

  Thereafter, the request-source terminal device 2X waits until response data DTA for the inquiry data IR is transmitted from each related terminal device 2Y until the expiration date (Yes in # 13). When the answer data DTA is transmitted, it is registered in the answer management table TA (# 14). When the response data DTA of all the related terminal devices 2Y are completed within the expiration date (Yes in # 16), processing such as determination of a request destination is started. This will be described later with reference to FIG.

  If the expiration date has passed (Yes in # 14), processing such as determination of a request destination is started even if inquiry data IR of some related terminal devices 2Y is not obtained. The inquiry data IR transmitted thereafter is not registered in the answer management table TA but discarded (# 15).

  In FIG. 12, the request source terminal device 2X determines a suitable request destination based on the response data DTA obtained from some or all of the related terminal devices 2Y. Specifically, the startable times indicated in the respective response data DTA are compared (# 21), and the related terminal device 2Y that has transmitted the response data DTA indicating the earliest startable time is determined as the request destination. (# 22).

  Formal request data RQ is generated (# 23), an expiration date is set for this (# 24), and it is transmitted to the related terminal device 2Y of the determined request destination (# 25). Thereafter, it waits for the receipt notification data AC to be transmitted from the related terminal device 2Y of the request destination (# 26).

  If the acceptance notification data AC is transmitted within the expiration date (Yes in # 27), it means that the formal request data RQ is accepted and formal job reservation is performed in the requesting related terminal device 2Y. Thus, the process for requesting a job is completed. Thereafter, when the requested job completion report data CP is transmitted from the requested related terminal device 2Y (# 29), post-processing such as deleting various data relating to the job from each table is performed, and All processing is complete.

  If the reception notification data AC is not transmitted within the validity period (No in # 27), the formal request data RQ is retransmitted, the request destination is re-determined, or a job is executed (#). 28).

  In FIG. 13, when the related terminal device 2Y receives the inquiry data IR from the request source terminal device 2X (# 31), the related terminal device 2Y determines whether the current date has passed the expiration date indicated by the inquiry data IR ( # 32).

  If the expiration date has passed (No in # 32), the inquiry data IR is discarded and the process is terminated. If the expiration date has not passed (Yes in # 32), it is determined whether or not the job indicated by the inquiry data IR can be executed (# 33).

  If the job can be executed (Yes in # 33), the startable date / time of the job is calculated (# 34), and response data DTA including a message that the job can be executed and the startable date / time is generated. Then, an expiration date is set for it (# 35), and it is transmitted to the request source terminal device 2X (# 36). The job data DTJ of the job is additionally registered in the job management table TJ before or after or in parallel with the process of transmitting the response data DTA (# 37). As a result, the job is temporarily reserved.

  On the other hand, if it is determined that the job related to the inquiry data IR cannot be executed (No in # 33), the response data DTA including a message to that effect is transmitted to the request source terminal device 2X (# 38).

  The related terminal device 2Y that has temporarily reserved the job continuously performs the processing of the flowchart of FIG.

  That is, it waits for formal request data RQ for the job. When the formal request data RQ is transmitted from the request source terminal device 2X by the expiration date set in the inquiry data IR of the job (Yes in # 41), the job is changed from the provisional reservation state to the formal reservation state. The status is changed (# 42), and when the turn comes, the job is executed (# 43). Then, after execution, the job completion report data CP including the processing result is transmitted to the request source terminal device 2X (# 44).

  On the other hand, if the formal request data RQ has not been transmitted from the related terminal device 2Y by the expiration date (No in # 41), the job data DTJ of the job is deleted from the job management table TJ, and the temporary reservation status Is released (# 45).

  According to the present embodiment, when transmitting data that requires a response to another terminal device 2, the terminal device 2 sets an expiration date for the data. The other terminal device 2 that has received the data transmits a response to the data if the expiration date has not expired, but discards the data and transmits a response if the expiration date has expired. do not do. As a result, useless responses are no longer exchanged for obsolete data, so that the communication load on the network 1 can be reduced as compared with the conventional case. In addition, since both terminal apparatuses 2 do not need to perform useless response exchange processing, the load on the terminal apparatus 2 can be reduced and resources can be used more efficiently than before.

  FIG. 15 is a diagram showing an example of the response management table TA2 storing the response data DTA received from the inquiry destination and the system information SI, and FIG. 16 is a process of the terminal device 2 when receiving a job request for transmitting a specific file It is a flowchart for demonstrating the example of the flow of this.

  In the present embodiment, the PC 7 as the job request source inquires about the job execution startable time, and determines the terminal device 2 that has answered the earliest startable time as the job request destination. As information for determining the job request destination, not only information on the startable time but also information on the specifications and resource usage of each terminal device 2 that is a candidate for the request destination, that is, system information SI may be used. In this case, the terminal device 2 may be configured as follows.

  When the terminal device 2 that has received the inquiry data IR regarding the job to be requested returns the response data DTA indicating that the job can be executed, the terminal device 2 uses its own system information SI together with the response data DTA as the inquiry source. Send.

  As shown in FIG. 15, the terminal device 2 that is about to make a job request associates the received response data DTA and system information SI with the host name of the terminal device 2 that is the transmission source and the job number of the job. And stored in the answer management table TA2. Based on the response data DTA and the system information SI obtained before the expiration date of the query data IR, that is, the response date of the query data IR, the job request destination is determined as follows.

  The terminal device 2 that has returned the reply data DTA indicating that the job can be executed is left as a request destination candidate, and the terminal device 2 that has returned the reply data DTA that indicates that the job cannot be executed is returned. 2 is excluded from the candidates for the request destination. The time required for each terminal device 2 remaining in the candidate to execute the job (hereinafter, “processing time”) is calculated (predicted) based on the contents of the job and the respective system information SI. What is necessary is just to calculate using a well-known method.

  The predicted date and time at which each terminal device 2 remaining in the candidate completes the job is calculated by adding the predicted processing time to the startable time (startable date and time) indicated in the respective inquiry data IR. Then, the terminal device 2 that is the earliest predicted date and time among the predicted dates and times calculated in this manner is determined as the request destination.

  Alternatively, if the job to be requested can perform distributed processing, whether or not it can be executed by another terminal device 2 for each processing unit (hereinafter referred to as “task”) included in the job. Further, the execution start time may be inquired, and the request destination may be determined based on the response to the execution start time and the system information SI. When determining the request destination for each task in this way, a known parallel processing technique is adopted, and the requesting terminal device 2 plays the role of the main CPU that manages the entire job, and the other terminal devices 2. May be configured to execute the task requested from the requesting terminal device 2 and return the result to the requesting terminal device 2.

  In this embodiment, the terminal device 2 that is about to request a job transmits inquiry data IR related to the job only to the other terminal device 2 that is directly associated with the terminal device 2. Then, the response data DTA is collected from these other terminal devices 2, and the request destination is determined. That is, only other terminal devices 2 that are directly associated with each other are set as candidates for the request destination. However, the present invention may also include other terminal devices 2 that are indirectly associated with each other as candidates for the request destination. In this case, in order to obtain the answer data DTA from these other terminal devices 2 as well, it is necessary to transmit the inquiry data IR to these other terminal devices 2. Therefore, when the terminal device 2 receives the inquiry data IR, the inquiry data IR is transferred to the terminal device 2 other than the transmission source of the inquiry data IR among the terminal devices 2 indicated in its connection table TL. What is necessary is just to comprise. As a result, the inquiry data IR transmitted from the terminal device 2 that is about to make a job request is sent not only to the other terminal device 2 that is directly related, but also to the other terminal device 2 that is indirectly related. Also delivered. However, the same query data IR is transferred only once so that the query data IR does not loop. Further, when the number of terminal devices 2 included in the network 1 is large, the range in which the inquiry data IR can be delivered is limited by setting the expiration date of the inquiry data IR shorter or setting TTL (Time To Live). May be.

  In this case, data such as the response data DTA, the formal request data RQ, the reception notification data AC, and the job completion report data CP are directly received by the terminal device 2 that is the request source and the terminal device 2 that is the formal request destination. If they are not associated with each other, they are exchanged between the two devices via another terminal device 2. The route can be determined by a known method based on the connection table TL of each terminal device 2.

  Alternatively, depending on the type of job, when the terminal device 2 that has received the inquiry data IR can execute the job related to the inquiry data IR, the terminal apparatus 2 immediately executes the job, and the execution result is displayed in the inquiry data IR. You may make it reply as a response. Hereinafter, the configuration in this case is such that each terminal device 2 is arranged as shown in FIG. 4 and the PC 7 is trying to download a specific file from another terminal device 2, that is, the PC 7 is the other terminal device 2. An example in which a request to execute a job for transmitting the specific file to the PC 7 is made will be described with reference to the flowchart of FIG.

  The PC 7 transmits inquiry data IR regarding whether or not the job can be executed to the terminal devices 2 (that is, the PC 2, the PC 6, the PC 8, and the PC 9) directly associated with the PC 7. At this time, an expiration date is set in the inquiry data IR. Further, TTL is set in the inquiry data IR.

  The terminal device 2 that has received the inquiry data IR first determines the expiration date of the received inquiry data IR (# 50, # 52).

  If the received inquiry data IR is not expired (Yes in # 52), it is determined whether or not the job related to the inquiry data IR can be executed (# 53). That is, it is determined by searching the local hard disk 20d whether or not the job has a file to be processed.

  If the file is found, that is, if the job can be executed (Yes in # 53), the file is transmitted to the PC 7 (# 56). That is, the job is executed.

  If the file is not found (No in # 53), the job cannot be executed, and the associated terminal other than the terminal device that has transmitted the inquiry data IR with reference to its own connection table TL. The inquiry data IR is transferred to the device 2 (# 55). For example, when the inquiry data IR is received from the PC 7, the PC 2 refers to the connection table TL2 in FIG. 5B and transfers it to the PC 3, PC 4, and PC 7. However, if the TTL is not larger than 0 (No in # 54), the transfer is stopped and the inquiry data IR is discarded. If the same inquiry data IR has been received in the past (Yes in # 51), the series of processing in steps # 52 to # 56 is stopped and the inquiry data IR is discarded.

  The terminal device 2 to which the inquiry data IR has been transferred also executes the processes of steps # 50 to # 56. With such a configuration, the inquiry data IR can be efficiently distributed to the terminal device 2 in the network 1.

  In the present embodiment, the expiration date of the transmitted data such as inquiry data IR or answer data DTA is determined immediately after reception. However, after the data is received and the expiration date is confirmed, it takes time for the internal processing, so that the reply to the received data cannot be performed within the expiration date. Then, even if a reply is made, since the expiration date has already expired, the reply data is discarded at the terminal device 2 on the receiving side, and this reply is wasted. In order to avoid such a situation, the expiration date of the received data may be appropriately determined during the reply process. If the expiration date expires during the process, the process may be interrupted at that time. As a result, it is possible to more effectively prevent the expired data from being returned in vain.

  In this embodiment, after making a temporary reservation for a job, until the temporary reservation is canceled or updated to an official reservation, the temporary reservation is rejected even if there is a new inquiry about another job. However, if the contents of the other job can be completed in a short time, a temporary reservation for the other job may be accepted.

  In the present embodiment, a personal computer has been described as an example of the terminal device 2. However, the present invention is an MFP (Multi Function Peripherals) that can accept job execution requests from other nodes in the network. The present invention can be applied to such image forming apparatuses, workstations, and other various processing apparatuses.

  In addition, the configuration of the entire network 1 and terminal device 2 or each unit, processing contents, processing order, table contents, and the like can be appropriately changed in accordance with the spirit of the present invention.

It is a figure which shows the example of the whole structure of a network. It is a figure which shows the example of the hardware constitutions of a terminal device. It is a figure which shows the example of a functional structure of a terminal device. It is a figure which shows the example of the logical topology of a terminal device. It is a figure which shows the example of the connection table of the terminal device linked | related like FIG. It is a figure which shows the example of the job management table of PC7. It is a figure which shows the example of the request job management table of PC7. It is a figure which shows the example of the reply management table of PC7. It is a flowchart explaining the example of the flow of a process of each terminal device when PC7 makes a job execution request with respect to one of the terminal devices associated with itself. It is a flowchart explaining the example of the flow of a process of each terminal device when PC7 makes a job execution request with respect to one of the terminal devices associated with itself. It is a flowchart for demonstrating the flow of a process in the request origin terminal device at the time of transmitting inquiry data. It is a flowchart for demonstrating the flow of a process in the request origin terminal device after receiving reply data. It is a flowchart for demonstrating the flow of the process in the related terminal device at the time of transmitting reply data. It is a flowchart for demonstrating the flow of the process in the related terminal device after temporary reservation. It is a figure which shows the example of the reply management table which stored the reply data received from the inquiry destination, and system information. 10 is a flowchart for explaining an example of a processing flow of a terminal device when a job request for transmitting a specific file is received.

Explanation of symbols

1 Network 2 Terminal device (node, information processing device)
202 Data receiving unit (first receiving means, second receiving means)
216 Data transmission unit (first transmission unit, second transmission unit)
AC reception notification data (second data)
DTA response data (response data, second data)
IR inquiry data (inquiry data, job execution inquiry data, first data)
RQ Formal request data (Job execution request data, first data)

Claims (4)

A communication method in a network composed of a plurality of terminal devices,
The first terminal device in the network associates job execution inquiry data for inquiring about job execution and first expiration date data indicating the expiration date with each other, and each second terminal in the network To the device,
Each of the second terminal devices relates to the job execution inquiry data when the expiration date indicated in the first expiration date data corresponding to the job execution inquiry data from the first terminal device has not expired. The reply data indicating the reply and the second valid period data indicating the valid period are associated with each other and returned to the first terminal device,
The first terminal device is configured so that any of the second terminal devices in the network is based on the answer data from the second terminal devices and the second expiration date data corresponding to the answer data. To execute the job,
The first terminal device transmits job execution request data for requesting execution of the job to the determined second terminal device;
A communication method characterized by the above. The second terminal device can start the job in the second terminal device as the answer data, the resource usage status of the second terminal device, or the second terminal device. Reply with data about
The communication method according to claim 1 . When the second terminal device receives the job execution inquiry data, the expiration date indicated by the second expiration date corresponding to the answer data related to the job execution inquiry data has expired or the job execution request of the job Until receiving data, restrict acceptance of requests for execution of other jobs from other terminal devices in the network,
The communication method according to claim 1 or 2 . When the expiration date indicated by the second expiration date data from the second terminal device has expired, the first terminal device executes the job excluding the second terminal device. Determine the terminal device to be
The communication method according to any one of claims 1 to 3.