Printer accounting

The following is a discussion of page counting on a Novell network (Page Counting and QView Pro)

With the advent of high speed printers, and fast queue systems for Novell networks, printing has become a high volume activity. Users are not forced to wait while their dot matrix printer pounds out their document line by line. It is understandable that network administrators now want to curtail the use of shared printers in an effort to limit waste and cut costs. One of the common questions about our product QView Pro is: "Can a page count be added to the log file that QView Pro generates?"

The scope of the "page counting" problem is very large. In a system that counts the number of pages printed, an accounting mechanism would be appropriate. This could be added as a total count of pages printed in an account for each user, or to deduct pages printed from each credited user account. After the credit has been exceeded, the print job can be canceled. To effectively accomplish this, the software (or hardware) solution would need to do one of the following:

1. The software can check with the printer and find out how many pages it has printed, and cut off the flow of data when it exceeds the credited number of pages, To do this, the software must be in the line of data flow, and not simply a monitor program. The only reliable means of accomplishing this would be to operate as a print server print server. Only a few printers will support this kind of query. Apple LaserWriters are among these. Some printers using Ethernet connections support this as well.
   
2. The software could analyze the print data and image or calculate what the printer will do with the print data before it gets printed. Again, the software would have to be in the line of data flow as a print server. The problem with this method is the amount of processor power required to process many print jobs. The software would have to support a wide variety of printers including (but not limited to) the following: PCL5, Epson mx/rx, HP Desk Jet/Color Desk Jet, QuickDraw, IBM Graphics, ImageWriters, in all the paper sizes, tractor feed, sheet feed, 8x11, A4, legal, envelope, etc. This would require the software to know many different types of printers in several configurations. Some print languages are easier to estimate the number of pages printed. It is reasonably easy to guess the number of pages of a print job in HP LaserJet languages. This is not the case for printer languages such as PostScript. Calculating the number of pages in a PostScript file can require quite a bit of time.

In short, the method of letting the print server software query the printer after each job to find the number of pages printed is much more reliable and faster than trying to analyze the print job data.

Consider the following print jobs:

In both cases the client has sent postscript data to the printer, In job 1, the postscript should be printed as ordered, possibly 2 pages of pictures. In job 2, the results will depend on the printer status before the job gets there. If the printer was set to default to PCL, you will get several hundred pages of text, and not 2 pages of pictures. This is an extreme example, however it does show how it becomes very hard to read a print job data file, and figure the number of pages.

About QView Pro:

QView Pro was designed to be a print queue monitor tool; a replacement for pconsole.exe. The log file function of QView was intended to provide some feed back to users who may wish to see if their print jobs are being processed, or simply are not being queued.

Because QView Pro is not a print server, it does not have the control over the printing process to provide page counting by the method of querying the network printers. Theoretically, it could process each print job data file, however this would be very processor intensive, and would severely decrease the speed of the print queue. For these reasons, a page counting feature is not available in QView Pro.

Other products:

There are several other products that are available that will assist in charging by the number of pages printed. These include accounting print server, and vending card readers. (Secure Design does not produce either product) The vending card readers are a hardware device that is attached to the printer. The user inserts a magnetic stripe card into the device. The card has a specific amount of printing credit encoded on it. The device counts the number of pages that move through the printer and deducts credit from the card. When the user's credit is exceeded the device will tell the printer the paper tray is empty.

Secure Design maintains a list of companies that make printer accounting systems on our web site.

QView Pro can still be useful in managing print queues with vending card devices or accounting print servers. For further information please see the section titled "Suggested Setups" in the QView Pro documentation.

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