Estimating data transmission rates

With bit-mapped graphic images, including text output from many word processing configurations, printer speed may be limited solely by how fast the data can pass through the workstation's print port to the printer.

Choose an interface that is fast enough to keep up with the bulk of the print jobs to be run on a particular printer. To do this, you will need to estimate the data transmission rate for that printer.

• For printers rated in characters-per-second (CPS), use the CPS rating for the preferred font and point size as the estimated data transmission rate. Assume that only print engine limitations will limit printer output.

• For page-per-second rated printers, estimate print data transmission this way:

• For a representative print job, count the number of pages to be printed.

• Print the job to a file and record the finished file size in bytes.

• Divide the total pages (pages-per-job) by the pages-per-minute and multiply by 60 to yield seconds-per-job.

• Divide the total bytes (bytes-per-job) by seconds-per-job to yield the bytes-per-second needed to keep up with the print engine.

  For example, a six-page job would take a minimum of 60 seconds on a 6-page-per-minute laser printer. If the job ``printed'' 12000 bytes (a likely low end for plain text), the target throughput is 0.2KB per second. The same job on a 17-page-per-minute printer would yield a target throughput of 0.6KB per second.

  For another example, a one-page graphic of 1 million bytes would target the 6-page-per-minute printer at 100KB per second and would target the 17-page-per-minute printer at 283KB per second.

  This method of estimating data transmission is not useful for PostScript or other page description language printing which requires print job formatting at the printer.