Printing has an interesting place in the seemingly long history of PC networking (although it has only been a little more than 20 years ); the ability to share printers, along with file sharing, was one of the key reasons personal computers were networked in the first place. A shared printer on a network is a printer that accepts print jobs from more than one computer.
When you connect a printer to a server on the network and configure it to share print resources with users on the network, it is referred to as a print server . Different terms are also often used to designate where the printer is actually located on the network.
A local printer is a printer that is directly attached to a server. The printer is only local, however, in relation to the server that it is attached to. This server will, obviously, serve as the print server for the printer.
A remote printer is a printer attached to a computer other than your server, which can be pretty confusing because the computer that the printer is attached to would consider the printer local. Whether a printer is local or remote will depend on which computer on the network you are using as your reference point.
A third type of network printer also exists: the direct connect printer. A direct connect printer is a printer that contains its own network interface, processor, and memory for print serving. These printers are typically attached directly to a network hub or switch using twisted-pair cable, just like any computer on the network.
Printers without direct connection hardware can be attached to devices (made by a number of vendors ), such as the Hewlett-Packard JetDirect external print server, and then connected directly to the network. The external print server provides at least one parallel port for connecting the printer and a CAT 5 Ethernet port for connection to the network hub.
Now that we know the different categories of printers that can be found on the network, we can discuss how network printing actually works. When a user prints a document from a network client using application software to a network printer, the redirector on the client machine sends the data out onto the network to the print server computer that controls the particular network printer.
The print server uses software called a print spooler to accept the print job and place this job in its print queue , which is just some of the computer's memory used to hold print jobs until they can be sent to the printer. When the printer is free to accept the print job, it is released from the print queue.
As with creating shares on the network, how printers and print servers are configured for network printing will vary depending on the NOS you are using. Check out Chapters 8, 9, and 10 for information on how to provide printing in the NetWare, Windows Server 2003, and the Linux environments, respectively.