JPH0679300B2 - Network system - Google Patents

Description

The present invention relates to a network system in which a data processing device and a printer having different communication protocols (hereinafter referred to as protocols) are connected on the same transmission medium.

[Conventional technology]

Conventionally, there is known a network system in which a host computer (hereinafter, referred to as a host) and a printer having different protocols are connected on the same logical network system. FIG. 11 is a configuration block diagram showing an example of a conventional network system. In the figure, 21 is a host having protocol 1, 22 is a printer having protocol 2, 23 is a gateway having protocols 1 and 2, and is equipped with a spool 24 which is a storage means for storing files and the like. In FIG. 11, the host 21
In order to send the above file to the printer 2 having a different protocol, first, the host 21 issues a file transfer command to the gateway 23 which absorbs the difference in the protocol. On the other hand, the gateway 23 accepts the request from the host 21, temporarily buffers the file in the spool 24, and sends the file to the printer 22 by the protocol 2.

[Problems to be Solved by the Invention]

However, the network system shown in FIG. 11 is premised on the host functioning as a client (active side), and therefore there is a problem that a host without a client function cannot actively transmit from the host. It was Further, since the file is temporarily buffered on the gateway and sequentially transmitted to the printer in block units, there is a possibility that the file may be lost due to a communication failure during the file transmission.

This invention can be used from a host that does not have a client function.
An object of the present invention is to provide a network system capable of transmitting a file and preventing loss of the file due to a failure during transmission of the file.

[Means for Solving the Problems]

In order to solve the above problems, in a network system according to the present invention, a single interface is connected to a network,
Data transmission / reception means for transmitting / receiving data according to the protocol of each device such as a host or printer, storage means such as a spool for accumulating files received by the data transmission / reception means, and a storage in the host at predetermined time intervals with respect to the host. If there is a file search method to search for the print request file and the print request file in the host,
The file is received by the protocol supported by the host and stored in the storage means, and the file stored in the storage means is transmitted by the protocol supported by the printer, and the transmission of the file to the printer is completed. A gateway including a file transmission unit that deletes the corresponding file in the storage unit when the print processing is completed and deletes the file in the host when the print processing by the printer is completed.

[Action]

The gateway connects to the host using a protocol supported by the host and checks for a print request file at predetermined time intervals. When the host has a print request file, the file is received on the gateway spool, and this file is sent to the printer using a protocol supported by the printer. Then, when the transmission of the file to the printer is completed, the file accumulated in the spool is deleted, and after receiving the print completion notification from the printer, the file on the host is deleted. In this way, the gateway checks the existence of a file in the host at predetermined time intervals, and if there is a file, it stores it in the spool and then sends it to the printer, so even if the host does not have a client function, Can be automatically transmitted. Further, since the file is accumulated on the host until the transmission to the print is completely completed and the print processing in the printer is completed, it is possible to prevent the loss of the file due to the failure during the file transmission.

〔Example〕

An embodiment of the network system according to the present invention will be described below.

FIG. 2 is a block diagram showing a schematic configuration of the network system according to the present invention. In the figure, 11 is TCP /
IP (Transmission Control Protocol / Internet Protoco
l) host with protocol, 12 is XNS (Xerox Networ)
a printer having the k System) protocol, 13 is a gateway having the TCP / IP protocol and the XNS protocol, and these are connected to a cable 14 which is the same logical network. It should be noted that only the host servo function used here is provided.

FIG. 1 is a block diagram showing the basic configuration of the gateway 13 described above, and the same parts as in FIG. The gateway 13 is connected to the cable 14 by a single interface (not shown), and the data transmission / reception unit 1 that transmits / receives data according to the TCP / IP and XNS protocols by the interface and the data transmission / reception unit 1 receives the data. A spool 2 that is a storage unit that stores files, a file search unit 3 that connects to the host 11 by FTP, and periodically searches for a print request file at predetermined time intervals, and a print request file in the host 11 Sometimes the file is a TC supported by host 11
At the time when the file receiving unit 4 which receives the P / IP protocol and stores it in the spool 2 and the file which is stored in the spool 2 are transmitted by the XNS protocol supported by the printer 12, and when the transmission to the printer 12 is completed. Spool 2
The file transmission unit 5 deletes the corresponding file in the host 11 and deletes the file in the host 11 when the printing process in the printer 12 is completed.

The gateway 13 includes a CPU (central processing unit),
It is composed of peripheral circuits whose main constituent elements are a main memory device and an auxiliary memory device.

FIG. 3 is a sequence for explaining a file transfer process between the host and the printer. In FIG. 3, transfer processing is performed between the host and the gateway by the TCP / IP protocol, and transfer processing between the gateway and the printer is performed by the XNS protocol. Further, these receiving process and transmitting process are processed in parallel.

Next, a processing procedure for automatic file transfer will be described with reference to the sequence of FIG. 3 described above with reference to the flowcharts of FIGS. 4 and 5.

First, the reception process between the host and the gateway will be described based on the flowchart of FIG.

First, the file search unit 3 of the gateway 13 makes a connection establishment request for file transfer from the data transmission / reception unit 1 to the host 11 (step 101). When the connection establishment request is accepted (step 102), the host 11 Log on to (step 103). Now you can work with files on the host. Next, the file receiving unit 4 sets the command cd (CWD) and moves from the root directory to the spool directory containing the print file (step 104). Then, the command ls (NLST) is set and the files under the spool directory are listed to determine whether or not there is a print request file (step 105). Here, if there is a print request file, the command get (RET
R) is set, the corresponding file is taken out and stored in the spool 2 (step 106). Next, notify the transmission process of the file transmission (step 107), and step 1
Return to 05.

Note that the command ls (NLST) can be
Set every 60 seconds).

When there is no file in the spool directory in step 105, it is determined that there is no file to be sent or the file is being sent to the print, and the process waits for a fixed time or until the sending to the printer is completed (step 10).
8). Next, the file transmission unit 5 determines whether or not the transmission of the file is completed by the notification from the transmission process described later (step 109), and when the transmission of the file is completed, the file is stored in the spool 2 in the gateway. Delete the file (step 110). Next, a notification from the transmission process described later determines whether the print processing is completed (step 111), and when the print processing is completed, the corresponding file on the host is deleted (step 111).
112).

Next, the transmission process between the gateway and the printer will be described based on the flowchart of FIG.

First, the file transmission unit 5 of the gateway 13 determines a request for a transmission process (step 201). Here, when a print request is made, a printer status inquiry is performed to know whether the printer is available (step 202). This status inquiry is performed periodically, for example, every 10 seconds, and the result is stored as status information. Next, it is determined whether or not the printer is available based on the result of the status inquiry (step 203). This judgment is made by checking the status information. Here, when the printer is not available, the printer waits for a fixed time (step 204) and returns to step 202. If the printer is available, a print result inquiry is made (step 205). This result inquiry is carried out periodically for the already transmitted file, and when the print processing by the printer is completed, the reception process (step 109 in FIG. 4) is notified of the end of the print processing. Next, it is judged whether there is a transmission file in the gateway (step 206), and if there is a transmission file, it is transmitted to the printer (step 207). Then, it is judged whether or not the file transmission is completed based on the notification from the printer (step 208), and when the transmission is completed, it is notified to the receiving process (step 110 in FIG. 4) (step 209).

If there is no request for the sending process in step 201, the printer status is inquired (step
210), it is determined whether the printer is available (step 211). Here, when the printer is not available, the printer waits for a certain time (step 212) and returns to step 201.
If the printer is available, a print result inquiry is made (step 213), and after waiting for a certain time (for example, 1 minute) (step 214), the process returns to step 201.

Further, when there is a stop request from the receiving process in step 201, stop processing is performed (step 215).

In the above-described embodiments, the network system in which the host and the printer are connected one by one has been described, but the network system according to the present invention can be applied to a system in which a plurality of hosts and a plurality of printers are connected. it can.

FIG. 6 is a block diagram showing a schematic configuration of a network system in which a plurality of hosts and printers are connected. This network system includes hosts A and B having a protocol 1 and printers A, B and C having a protocol 2.
And a gateway GW having protocols 1 and 2. An information file describing information on all hosts and printers is stored in a memory (not shown) of the gateway GW. The format of the host information file is shown in FIG. 7, and the format of the printer information file is shown in FIG.

FIG. 9 is an explanatory diagram showing the relationship between the spool in the host and the printer. In FIG. 9, host A has a spool A for printer A and spool B for printer B, and host B has a spool A for printer B and a spool B for printer C. Further, the gateway GW has three spools A to C corresponding to the printers A to C. The spool in each host has a one-to-one correspondence with the printer.

FIG. 10 is an explanatory diagram of a reception process and a transmission process of a file generated by the gateway. File transfer processing between a plurality of hosts and printers will be described below with reference to FIG. Since the basic processing procedure for transmitting / receiving a file has been described with reference to FIGS. 4 and 5, an outline of the file transfer processing will be described here. Also, description of the exchange of commands is omitted.

First, before sending / receiving a file, the gateway GW creates a file reception process for the host and spool described in the host information file, and at the same time sends the file to the printer described in the printer information file. Spawn a process.

First, the receiving process logs on to the host, periodically checks if the file exists in the host's spool, and if the file exists, stores it in the spool in the gateway corresponding to the host's spool. Notify the file sending process. When the sending process is notified by the receiving process to store the file,
The file is sequentially transmitted to the corresponding printer. After the transmission, when the print completion is received from the printer, the reception process is notified. When receiving the print completion, the reception process deletes the corresponding file on the host.

In the above-described embodiment, an example using XNS and TCP / IP as the network protocol has been described, but another protocol may be used as long as it has a similar function.

〔The invention's effect〕

As described above, in the network system according to the present invention, the gateway side logs on to the host, checks whether or not the print request file exists in the host at predetermined time intervals, and the print request file exists in the host. When it exists, the file is stored in the spool in the gateway, and after the file transmission to the printer is completed, the file is deleted in the gateway. Therefore, even a host having no client function can automatically transfer a file to a printer having a different protocol via the gateway.

Also, files are stored in the gateway until the transmission to the printer is completely completed, and the files on the host are deleted only after the printer has finished printing after the printer has finished sending. Therefore, it is possible to prevent the loss of the file due to the communication failure during the file transmission.

Further, by storing the host and printer information files in the gateway, automatic transfer is possible even in a network system in which a plurality of hosts and printers are connected.

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic configuration of a gateway, FIG. 2 is a block diagram showing a schematic configuration of a network system according to the present invention, and FIG. 3 is a diagram for explaining a file transfer process between a host and a printer. Sequence Diagram,
FIG. 4 is a flow chart showing a reception process between the host and the gateway, FIG. 5 is a flow chart showing a transmission process between the gateway and the printer, and FIG. 6 is a schematic configuration of a network system in which a plurality of hosts and printers are connected. FIG. 7 is a block diagram, FIG. 7 is an explanatory diagram showing the format of a host information file, FIG. 8 is an explanatory diagram showing the format of a printer information file, and FIG. 9 is an explanatory diagram showing the relationship between spools in the host and printers. FIG. 10 is an explanatory diagram of a reception process and a transmission process of a file generated by the gateway, and FIG. 11 is a configuration block diagram showing an example of a conventional network system. 1 ... Data transmission / reception unit, 2 ... Spool, 3 ... File search unit, 4 ... File reception unit, 5 ... File transmission unit, 11 ... Host, 12 ... Printer, 13 ... Gateway, 14 ... …cable.

Claims (1)

[Claims] 1. A network system in which at least one data processing device and at least one printer having a protocol different from that of the data processing device are connected on the same transmission medium, and are connected to the transmission medium by a single interface.
Data transmission / reception means for transmitting / receiving data in accordance with the respective protocols via the interface, storage means for accumulating files received by the data transmission / reception means, and data storage device within the data processing device at predetermined time intervals. A file search means for searching a file; and a file receiving means for receiving the file in a protocol supported by the data processing device when the file exists in the data processing device and storing the file in the storage means; The specified file in the storage means is deleted when the transmission to the printer is completed, and the file in the data processing device is deleted when the print processing in the printer is completed. A file transmission method to be deleted and a gateway consisting of Network system, characterized in that digit.