JPH064239A - LAN printer server system - Google Patents

Abstract

(57) [Abstract] [Purpose] To improve the efficiency of print processing in a LAN printer server system. [Configuration] An output switching unit is provided in the printer server, and if the specified printer cannot be used due to a failure or is in use by another print command, the output destination of the print data is automatically output to another printer. If the print data being transferred to the printer server reaches a certain amount, the printer server is caused to start the printing process of the printer, and the client transfers to the printer server. And the output operation from the printer server to the printer are performed in parallel to shorten the print output waiting time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer server capable of sharing a printer in a local area network (Local Area Network, hereinafter referred to as LAN), and is particularly suitable for efficiently performing print processing. And a printer server system of a simple LAN.

[0002]

2. Description of the Related Art A LAN is a limited local computer network such as one building or premises, and is used to connect so-called personal computers, workstations, host computers, etc. to digital circuits such as optical fiber cables and coaxial cables. It is possible to transfer information between each device. By using such a LAN, a plurality of terminal computers (hereinafter, referred to as clients) can share the printer through a computer (hereinafter, referred to as a printer server) that controls the printer. In addition, such L
The AN is described, for example, on pages 2658 to 2673 of "Electronic Information and Communication Handbook" (published by Ohmsha in 1988) edited by the Institute of Electronics, Information and Communication Engineers.

However, conventionally, when a printer is shared on a LAN, the operation method of the printer server controlling the printer is often different from that of the client, and the printer output is not normally performed. , Not everyone can deal with. Therefore, if the printer specified by the client is not operating due to some failure, the client user (user of the terminal) may not be able to obtain a print output. In such a case, the client user who knows the failure handles it by switching the connection of the printer server.

Further, conventionally, when a printer is shared on a LAN, when a print request from one client has already been accepted, print requests from other clients wait for printing in the printer server. Put in a queue. Therefore, the time until the print output is obtained is delayed.

Further, conventionally, print output is handled as a series of data even if one document extends over many pages. In a stand-alone environment where each computer occupies its own printer, this is not a problem because it is output directly to the printer, but on the LAN, once all documents are transferred from the client. Unless it is completed, there is no output from the printer server to the printer. Therefore, the time required for the printing process becomes long.

FIG. 5 is a block diagram showing the configuration of a conventional LAN printer server system. The LAN printer server system has a configuration in which printers 53 and 54 are connected to a client 51 and a printer server 52 connected by the LAN 50, respectively.
Is an application program 55 that issues a print command or print data, a redirector 56 that distributes the print command issued by the application program 55 to the printers 53, 54, and a printer that controls the print output of the printer 53. The printer server 52 includes a driver 57, and the print server 52 includes a print queue file 58 for receiving a print command from the client 51 and a printer driver 59 for controlling print output by the printer 54.
And.

In the LAN having such a configuration, the process for the print request from the client 51 to the printer server 52 is performed as follows. First, when the client 51 can access the printer 54 of the printer server 52, the print command issued from the application program 55 of the client 51 is passed to the redirector 56. The redirector 56 determines whether the received print command is for the printer 53 connected to the client 51 itself or for the printer 54 connected to the printer server 52.

When the print command issued from the application program 55 is a command to the printer 54, the redirector 56 switches the output destination of the printer device to the printer server 52 and opens the device. At the same time when this device is opened, the print waiting file 58 of the printer server 52 is opened,
The redirector 56 writes the print data into the print waiting file 58. When the client 51 finishes transmitting the print data for one document, the client 51 closes the printer device. Along with the closing of the printer device of the client 51, the printer server 52 side closes the print waiting file 58 and outputs it to the printer 54 via the printer driver 59 of its own.

As described above, in the conventional printer server system in the LAN, the printing operation in the printer server 52 is always performed in the unit of one document. When the client 51 outputs a print command to the printer server 52, the printer server 52 starts outputting the print data sent from the application program 55 on the client 51 side to the printer server 52 to the printer 54. This is after the transfer of all the documents to be printed from the client 51 is completed. Therefore, as shown in FIG. 6, the time until the print output result is finished is delayed.

FIG. 6 is an explanatory diagram showing the time required for the print processing by the printer server system of the LAN in FIG. This figure shows a comparison of the processing time for printing a document consisting of three pages in each of the printer 53 and the printer 54 in FIG. 5, and 61 is the processing time on the client 51 side in FIG. , 62 are processing times on the printer server 52 side in FIG. T at processing time 61
(11) to T (13) are transfer times for transferring the respective print data of pages 1 to 3 from the client 51 of FIG. 5 to the printer 53, and T (2 in the processing time 62).
1) to T (23) are from the client 51 in FIG. 5 to the printer server 52, and T (31) to T (33) are
From printer server 52 to printer 54 in FIG.
It is a transfer time for transferring each print data of three pages.

Incidentally, here, the printer server 54 of FIG.
And the data transfer rate of the client 53 are equal (T (11) = T (31), T (12) = T (3
2), T (13) = T (33)). Further, since the time required for code conversion and bit map expansion performed by the application program at the time of printing is the same in both cases, this case is not considered. Under these conditions, LA
5 through the N (processing time 62) to the printer 53 directly connected to the client 51 in FIG. 5 (processing time 61), the client 51 of FIG. To printer server 52
Time to output print data to (T (21) + T (22)
The time until the print output result is finished is delayed by + T (23). This delay time increases as the size of the document increases.

[0012]

The problem to be solved by the prior art is that in the prior art, when the designated printer is not operating due to some trouble, the user himself / herself
When it is necessary to switch the connection of the printer server, and when there are print requests from multiple clients for the same printer, the printer waits for printing, and further transfer of all print data to the printer server is complete. Since the printing process by the printer is started later, the printing process result cannot be obtained promptly. An object of the present invention is to solve these problems of the prior art, and to provide a LAN printer server system that can shorten the print processing time at the printer on the printer server side and can improve the efficiency of processing related to printing. Is.

[0013]

In order to achieve the above object, a LAN printer server system of the present invention comprises:
(1) In a LAN printer server system including a printer server that controls the operation of a plurality of connected printers and a plurality of clients that share printers via the printer server, the client is designated by the client as the printer server. Based on the operating status of the printer,
An output switching unit that switches the printer that outputs the print data from the client is provided. (2) In the LAN printer server system according to (1) above, the output switching unit includes a printer state determination unit that determines the online state and the offline state of the printer designated by the client, and the printer designated by the client is designated. If the printer is in the offline state, another printer in the online state is extracted and the output destination printer is switched. (3) In the LAN printer server system according to (1) or (2), the output switching unit is a queue for print data from another client of the printer designated by the client. If the specified printer is equipped with a waiting status determination unit that determines the status, and if the specified printer is in the print processing status from another printer, the printer that can print the print data from this client earliest is extracted and output. It is characterized in that the previous printer is switched. Further, (4) L described in any one of (1) to (3) above
In the printer server system of AN, the print output destination switched by the output switching unit is output to the printer server as an output management file accessible from the client.
It is characterized in that an output information registration unit for registering in the storage unit provided is provided. (5) In the LAN printer server system according to any one of (1) to (4) above, data division for dividing print data to be output to the printer into a predetermined specific data amount to a client And the printer server starts transferring the received print data to the printer after the reception of the first print data divided by the data dividing unit is completed. (6) In the LAN printer server system according to (5), the client is provided with a data delimiter detection unit that detects a predetermined delimiter code from print data to be output to the printer, and the data division unit is provided. Is characterized by dividing the print data to be output to the printer into a predetermined specific data amount based on the detection operation of the data delimiter detection unit.

[0014]

In the present invention, the printer server automatically sets the output destination of print data to another printer when the designated printer cannot be used due to a failure or is being used by another print command. Switch to. As a result, the client user can obtain the print result without switching the printer connection or operating the printer server by himself, and the time required for the print processing can be shortened. When the print data transferred to the printer server reaches a certain data amount, the client causes the printer server to start the print processing of the printer. Then, the output operation from the client to the printer server and the output operation from the printer server to the printer are performed in parallel to shorten the waiting time for print output.

[0015]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the configuration of the LAN printer server system of the present invention according to the present invention. The LAN printer server system of this embodiment is configured by connecting two clients 1 and 2 and one printer server 3 by a LAN 6 composed of an optical cable or a coaxial cable. The printer server 3 has a plurality of printer servers. The printers 4a to 4c and the storage device 5 are connected.

The client 1 is an application program (A in the figure) for issuing print commands, print data, and the like.
11) and this application program 1
1 is assigned to the printers 4a to 4c, a data delimiter detection unit 13 for detecting a delimiter code of print data set in advance and a data delimiter detection unit 13 according to the present invention. And a data dividing unit 14 that divides the print data from the application program 11 based on the detection operation.

The printer server 3 includes clients 1, 2
Print-ready file that captures print commands from
31), a printer driver (described as PRN in the drawing) 32a to 32c for controlling print output of each of the printers 4a to 4c, and a printer 4a designated by the clients 1 and 2 according to the present invention. 4c to 4c and print waiting file 3 corresponding to printers 4a to 4c
The printer state determination unit 33 that determines the state 1
The printer driver 32a to 32c, each of which has a different device name, includes an output switching unit 35 that performs necessary switching control based on the determination result of the waiting state determination unit 34.
And the printers 4a to 4c are made to correspond one-to-one and are provided to the clients 1 and 2 as shared resources.

The printer server 3 also includes an output information registration unit 36 according to the present invention, and which printer 4a-4
In order to inform the users of the clients 1 and 2 whether or not the print output is made to c, the output management file 5a is opened (created) in the storage device 5 accessible from the clients, and "print The "command source client name", "print destination printer name", "print completion time", etc. are written.

The operation of the printer server system having such a configuration will be described below. First, the operation of the printer server 3 according to the present invention in response to a print request from the client 2 will be described. The client 2 may be a conventional one that does not include the data delimiter detection unit 13 and the data division unit 14 according to the present invention provided in the client 1, or may have the same configuration as the client 1.

When printing, the client 2 is connected to the printer driver 32a corresponding to the printer 4a of the printer server 3, for example, by the user. Then, the print data is sent to the printer server 3 via the LAN 6.
Transfer to. In the printer server 3, the print data from the client 2 is stored in the print waiting file 31,
At this time, the waiting state determination unit 34 searches the contents of the print waiting file 31 to determine whether or not the command for the designated printer 4a is unique within the LAN configuring this system. The determination unit 33 accesses the designated printer 4a corresponding to the printer driver 32a and determines the state of the printer 4a.

If there is only one command for the designated printer 4a in the discrimination result by the waiting state discriminating section 34,
The printer server 3 does not perform the switching operation by the output switching unit 35, but directly performs the process of transmitting the print data to the printer 4a. However, if another print job exists before this and printing cannot be immediately performed on the printer 4a, the printer server 3
The output switching unit 35 switches the output destination to the other printer drivers 32b to 32c and performs the same processing as that of the first printer 4a.

This operation is sequentially repeated, and when a printer that can print out without waiting is encountered, print data is transmitted to the printer. If there is no other printer that can print immediately, the output switching unit 35 calculates the total amount of data in the queue of each printer, and prints the print data to the printer with the smallest total amount of data. Put in.

Further, according to the discrimination by the printer state discriminating section 33, the designated printer 4a and the switching destination printer 4b are selected.
However, if it is in the unreceivable state due to power off or select off, the printer server 3
The output switching unit 35 switches the output destination to another printer driver 32c, accesses another printer 4c, and performs the same processing as the printers 4a and 4b. This process is sequentially repeated, and when a printable printer is encountered, print data is transmitted to the printer.

When the transmission of the print data is completed in this way, the printer server 3 outputs the output information registration unit 36.
By doing so, the output management file 5a is opened in the storage device 5 in the printer server 3 for each print job.
"Client name of print command source", "printer printer name", "print completion time", etc. are written. The output management file 5a is accessible from the client, and the user of the client 2 can know to which printer the data has been printed out.

Next, the operation of the client 1 according to the present invention will be described. In the LAN of this embodiment, output from the client 1 to the printer 4a of the printer server 3 is performed as follows. When the client 1 can access the printer 4a of the printer server 3, the print request and print data issued from the application program 11 of the client 1 waits for the open print of the printer server 3 via the redirector 12. It is sent to the file 31.

At this time, in the client 1, the data delimiter detection unit 13 sequentially checks the code of the print data, and if a code of a predetermined delimiter, for example, a page break instruction code is detected, the print data is 1 It is detected that the data amount exceeds the page. Then, based on this detection result, the client 1 causes the data dividing unit 14 to temporarily close the printer device corresponding to the printer 4a of the printer server 3, and if print data to be output still remains, the client device 1 , Open to output subsequent print data.

By the closing operation by the data dividing section 14, the printer server 3 side closes the print waiting file 31 in the spool and starts transferring the data to the printer 4a. And on the printer server 3 side,
The work of spooling the print data transferred from the client 1 as the print waiting file 31 and the work of transferring the print waiting file 31 to the printer 4 can be simultaneously performed in parallel. As a result, the time required to complete printing can be shortened as compared with the print processing time in the conventional technique shown in FIG.

FIG. 2 is an explanatory diagram showing the time required for the printing process by the printer server system of the LAN in FIG. In the figure, reference numeral 60 denotes a processing time related to printing by the printers 4a to 4c in FIG. 1, and processing times 61 and 62 related to printing of a three-page document by the printers 53 and 54 in FIG. Shows a comparison with. In the present embodiment, when the print data of pages 1 to 3 is transferred from the client 1 of FIG. 1 to the printer server 3, the time point when the transfer of the first page is completed (processing time T (2
After 1), the printer server 3 in FIG. 1 starts the transfer of the one page to the printer. Then, in parallel with the transfer of one page to the printer by the printer server 3 of FIG. 1, the transfer from the client 1 of FIG.
The print data of page 3 is transferred. As a result, the time required to complete printing can be shortened compared to the processing time 62.

Next, referring to FIG. 3 and FIG. 4, FIG.
The operation of the printer server system of the LAN according to the present invention will be described. FIG. 3 is a flow chart showing a first embodiment of the operation of the printer server system of LAN in FIG. 1 according to the present invention. The client issues a print request to the specified printer (step 30).
1) The print data is transmitted from the client to the printer server and stored in the printer server (step 30).
2). Upon receiving the print data, the printer server determines whether or not the designated printer is online and can print (step 303).

The printer server, if the designated printer is online and ready to print (step 30)
4) If it is impossible to print to the designated printer, the printer server determines another printer that can print (steps 305 and 306), and prints to the printable printer. Send data (step 30)
7). Then, the output information is written in the output management file (step 308). If there is no printable printer, the error information is written in the output management file (step 309). The user of the client can know which printer the print data was output by referring to the information of this output management file (step 310).

FIG. 4 is a flow chart showing a second embodiment of the operation of the printer server system of LAN in FIG. 1 according to the present invention. The client issues a print request to the specified printer (step 401), the print data is transmitted from the client to the printer server, and is stored in the printer server (step 402).
Upon receiving the print data, the printer server determines whether the designated printer has another print job and has a queue (step 403).

If the designated printer does not have a queue and is ready to print immediately (step 404), the printer server has a queue for this designated printer and also for the designated printer, and immediately If printing is impossible, another printer that does not have a queue and can print immediately is determined (steps 405, 40).
6) The print data is transmitted to the printable printer (step 407).

If there is no other printer that can print immediately in step 406, the total data amount in the queue of each printer is calculated (step 408).
Then, the print data is queued to the printer with the smallest total data amount (step 409), and when the turn comes, the print data is transmitted to this printer (step 410). The printer server writes the name of the printer that has transmitted the print data and the like as output information in the output management file (step 411). The user of the client can know which printer the print data was output by referring to the information of this output management file (step 412).

As described above with reference to FIGS. 1 to 4, in the LAN printer server system of this embodiment,
When a certain printer is offline or when another printer is occupying the printer, the printer server automatically detects another available printer and switches the output destination. As a result, it is possible to reduce wasteful time required for print output and effectively use the printer, which is a shared resource of the LAN. Also, the client side divides the print data to be transferred to the printer server. As a result, the print start time of the printer is shortened and the time required for the print processing can be shortened. The present invention is not limited to the embodiment described with reference to FIGS. For example, in FIG. 1, the print waiting file 31 may be stored in the storage device 5.

[0035]

According to the present invention, when a designated printer is not operating due to some kind of failure or when there are print requests from a plurality of clients to the same printer, it is immediately and immediately performed. You can select a printable printer to perform print processing, and you can start print processing on the printer without waiting for the completion of transfer of all print data to the printer server. It is possible to shorten the time required for printing, to obtain the print processing result promptly, and to improve the efficiency of the printing processing of the LAN printer server system.

[0036]

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a configuration according to the present invention of a printer server system of a LAN of the present invention.

FIG. 2 is an explanatory diagram showing a time required for print processing by the printer server system of the LAN in FIG.

3 is a flow chart showing a first embodiment of the operation of the printer server system of LAN in FIG. 1 according to the present invention.

FIG. 4 is a flowchart showing a second embodiment of the operation of the printer server system of LAN in FIG. 1 according to the present invention.

FIG. 5 is a block diagram showing a configuration of a conventional LAN printer server system.

6 is an explanatory diagram showing a time required for print processing by the printer server system of the LAN in FIG.

[Explanation of symbols]

 1, 2 client 3 printer server 4a to 4c printer 5 storage device 5a output management file 6 LAN 11 application program 12 redirector 13 data delimiter detection unit 14 data division unit 31 print waiting file 32a to 32c printer driver 33 printer status determination unit 34 waiting State determination unit 35 Output switching unit 36 Output information registration unit 50 LAN 51 Client 52 Printer server 53, 54 Printer 55 Application program 56 Redirector 57 Printer driver 58 Print waiting file 59 Printer driver 60 to 62 Processing time

Claims (6)

[Claims] 1. A printer server for controlling the operation of a plurality of connected printers, and a printer server,
L consisting of multiple clients sharing the above printer
In the printer server system of AN, the printer server is provided with output switching means for switching the printer that outputs the print data from the client based on the operating state of the printer specified by the client. Server system. 2. The LAN printer server system according to claim 1, wherein the output switching means includes a printer status determining means for determining an online status and an offline status of a printer designated by the client,
A printer server system for a LAN, wherein when the designated printer is in an offline state, another online printer is extracted and the output destination is switched. 3. The LAN printer server system according to claim 1 or 2,
The output switching unit includes a wait state determination unit that determines a queue state according to print data from another client of the printer designated by the client, and the designated printer determines that the print data from another client If processing is in process, the printer that can print the print data from the client earliest is extracted, and the output destination printer is switched.
AN printer server system. 4. The LAN printer server system according to any one of claims 1 to 3, wherein the print output destination switched by the output switching means is accessible from the client to the printer server. A printer server system for a LAN, characterized in that output information registration means for registering in a storage means provided as an output management file is provided. 5. The LAN printer server system according to any one of claims 1 to 4, wherein data for dividing print data to be output to the printer to the client is divided into predetermined specific data amounts. A LAN printer characterized in that a dividing means is provided, and the printer server starts transfer of the received print data to the printer after completion of reception of the first print data divided by the data dividing means. Server system. 6. The LAN printer server system according to claim 5, wherein the client is provided with data delimiter detection means for detecting a predetermined delimiter code from print data output to the printer, and the data is delimited. The dividing unit divides the print data to be output to the printer into a predetermined specific data amount based on the detection operation of the data delimiter detecting unit.
AN printer server system.