Printer Properties - Ports

[Andy]

I hope this is an easy question for you folks to answer.

When I look on a workstation at the printers and right
click and select properties, one of the options
is "Ports". What is the significance of the ports? It
says that it prints to the first checked port in the
list. My first question is why I can only select one
port? Why are there different ports available for each
printer?

Here are the settings for two different printers:

This one prints directly to the printer (192.168.2.50):
1 - \\GP335\Print - Type: Canon GP300-405 PCL; Where:
\\gp335\print

Port: (ticked) - \\gp335\print
Type: Local Port Printer: Print


This one prints through the server ("orange")
2 - \\orange\Canon GP335PCL 5e - Type: Canon GP335 PCL
5e; Where: \\gp335\print

Port (not ticked): IP_192.168.2.50
Description: Standard TCP/IP Port Printer: Canon
GP335 PCL 5e
Port: (ticked) \\gp335\print
Description: Local Port Printer: Canon GP335 PCL
5e


As you can see, both printers have the same port selected
and yet one prints direct to the printer and one prints
through the server. Why is this?

Can anyone help me? I'm new at this game?
Thanks
Andrew

 

[C.D.Kuder]

In brief:
The term port (or printer port in this case) , also sometimes called a
queue, is context sensitive, and in this case is used to identify a
destination for the data to be printed to. It isolates the actual hardware
or path to the hardware from the source of the data, and might also be
called a route to the printer.

It's not uncommon to have more than one path to a printer. This might be
because the printer is attached to a local port on a computer, and is also
shared. Or, the printer might support more than one protocol, such as
postscript, raw, and HP PCL. In your case the printer seems to have a TCPIP
or similar connection on a LAN, and also has an assigned print server. The
printer might be accessible only thru the server, or a particular PC might
have software installed that allows it to talk to the printer directly. A
print server may have an ASCII text queue, a postscript queue, and a native
printer queue. The print server might just spool the data, or also
accomplish some sort of data conversion, and possibly audit tracking of
printer use.

It's also possible (in a limited fashion) to connect (redirect) what is
normally considered to be a local port, such as LPT1: to a LAN or shared
printer.

With some USB connected printers, it's necessary to establish a "network"
port to (of all things) print from a DOS program, even though the printer is
a local USB connected printer.

 

[Andy]

Thanks for taking the time to reply. It was very helpful.

Andy

 

[Bruce Sanderson]

When you open the Ports tab, you see all of the printer ports that exist on
the computer. If the printer properties that you are looking at is a
Network Printer, you actually see the Printer Ports on the print server
computer.

Using the Ports tab, you can assign the Printer (print queue) to a different
port (assuming you have the appropriate authority to do this). This can be
useful if particular print device breaks and there are documents waiting to
print.

Generally speaking, each Port corresponds to a particular physical print
device (physical printer).

The "Printers" that one sees and uses in Windows are logical objects that
have characteristics that, if properly configured, correspond to the
characteristics of the physical print device associated with the "Port" that
the physical print device is actually connected to.

You can assign multiple "Printers" (print queues) to be serviced by the same
physical print device (port). This is sometimes handy if, for example, you
replace two printers with one that can print faster - the users can still
print to the "printer" they are familiar with. Another example is if you
want to use two or more different printer drivers for the same physical
printer for some reason (e.g. a PCL driver and a Postscript driver).

Also, if you add a check mark to the "Enable printer pooling" check box, you
can assign several ports (and thus print devices) to a single "Printer"
(print queue). This is useful if you have several (essentially) identical
printers in close physical proximity; when a document arrives in the print
queue, it will print on whichever of the ports (print devices) happens to be
idle. So, the user's see a single "Printer" (print queue) that is serviced
by multiple print devices, thus increasing the available printing capacity.

See "print device", "port", and "printer" at
http://members.shaw.ca/bsanders/Glossary.htm.

The "Description" column on the Ports tab has important information. For
example, if it says "Standard TCP/IP Port", this tells you that the physical
print device is associated with the LAN adapter the printer is connected to
(either internal to the printer's case or externally). If it says "Local
Port", and the name in the "Port" column is in the form \\computer\printer,
this tells you that the printer is a Local Printer on a "Local Port" that is
redirected to printer shared from another computer.

If the printer is a true Network Printer, there is no "port" for it on the
local computer - what you see is the information about the port on the print
server computer.

In a networked environment, the situation can be a bit confusing at first.
You need to distinguish between the printer ports on the local (client)
computer and those on the print server computer. On the local computer, if
you open the Printers folder, click File, Server Properties, Ports, you see
the ports on the local computer - if all of your printers are true Network
Printers, you won't see any of the ports for those printers. Again, on the
local computer,

1. click Start, Run
2. key \\ followed by the name of the print server computer (e.g. \\gp335),
press Enter
3. in the right pane of the Explorer window that opens, go to the bottom of
the list and double click "Printers" or "Printers and Faxes"
4. now you see the printers as defined on the print server. Click File,
Server Properties, Ports - now you see the printer ports on the print server
computer.