What is it?
Besides shared file storage, one of the most common features of a local area
network is the use of shared printers. Because of the relatively high cost of
printers, and the intermittent use of printers by the user community, it makes
economic sense for a group of users in close proximity to share a printer.
Network printing is generally implemented through the use of print servers
and print queues. The classic print server was a system to which the network
printers were connected. The print server assigns print jobs to various
printers based on their availability and the printing instructions, and monitors the
status of the printers and print jobs. A print queue is a temporary storage area
for print jobs, typically residing on the file server hard disk, that holds a job
until the print server can assign it to a printer. 
What does it do?
Print queues are generally assigned to specific printers, although queues can be
redirected to different printers if necessary. Printers are assigned to specific
print servers to be managed. In todays network environment, a print server can
be a system on the network dedicated to this function, or the print server may
run as a process on the file server. There are also devices such as pocket print
servers and HP Jetdirect cards, that act to the network like a print server for
the printers to which they are attached. Printers can be either locally attached,
that is directly attached to the print server, or they can be remotely attached,
in which case a user can have a printer attached to his workstation that is
available to be used by the print server, and therefore shareable. A small
software routine, loaded when the workstation boots, provides this
functionality.
How is it used?
Network printing is enabled through a process called print redirection. A PC
generally expects that when it commands a file to be printed, the file will be
directed to one of its parallel printer ports. The client software that enables a
workstation to log on and function on the network also provides the ability to
intercept these print commands, and redirect the print job down the network to
a print queue. Once this has occurred, the workstation thinks it has printed the
job and goes on about its business. Meanwhile, the print job waits its turn in the
queue, until its desired printer becomes available. When the print server for the
target printer senses that it is ready for a new job, it will access the print queue
and forward the job to the printer.
Network printing offers several key advantages. Economies of scale can be
achieved through allowing users to share printers, rather than having one on
each workstation. Each user has a greater range of printing options, by having
access to several different printers, such as a high-quality laser printer, a color
printer, and a fast dot-matrix printer for draft work or long reports. If a printer
fails, print queues can be redirected to a different printer.
Lastly, a user can print his file in a location geographically removed from his
workstation.
Where do I get more information?
Contact your local CBV Office.
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