Networking Principles V: Network Printers
A Few Terms
- The Print Device. Most people call this the printer but Windows calls it a print device. This is the physical printer hardware connected either locally or on the network.
- The Printer Driver is the software provided by the printer’s manufacturer that allows users to prepare a document for printing.
- The Printer is the logical device created on a computer to allow output to paper or other physical media.
- The Print Server is the computer that hosts one or more printers for use by network clients. This server handles the queuing and submitting print jobs to the print device.
Steps in the Printing Process
- The application sends the data to the printer for processing.
- The printer receives the data and uses the printer driver to render the print job into a form that can be processed by the print device. By default, the order in which jobs are processed amounts to “first come, first served.” The printer processes jobs in the order they are received. If circumstances warrant, though, you can change the order in which print jobs are processed.
- The print server processes the jobs in the order they are queued by sending them to the print device.
- The print device transfers the data to a physical medium. The most common physical medium is paper; however, the medium can take different forms, such as the plastic your driver’s license or ID card is printed on. Some printers can even create three-dimensional “sculpted” output.
Printing Formats
In Windows Server 2008 and Vista, the printer driver renders the print job in one of two formats.
The Enhanced Metafile (EMF) format is a format designed for use with Windows 2000, XP, and Windows Server 2003. The application data is converted into an EMF file using the printer driver assigned to the printer. Then, the printer sends the job to the print server, where it is stored in the spooler. The spooler then uses the printer driver to render the job file into its final format so the print device can process the job. In Windows-based printers, the format is called PCL. This process is also known as Graphics Device Interface (GDI)-based printing.
XML Paper Specification (XPS) format is new to Windows Server 2008 and Vista. This format is a platform-independent document format that does not require the job file to be converted at different steps of the process like EMF jobs. XPS does require print devices that support XPS.
Important Note: When installing new printers, please make certain you have the correct printer driver for the print device! Otherwise, anything you print may come out with erroneous formatting, funny characters, blank pages, and other print errors. If you aren’t sure, look for the disk that came with your printer or right down the model number and search for it on the manufacturer’s website.
Windows Printer Types
Windows Server 2008 supports printing using either locally attached printers or network attached printers.
A locally attached printer is connected directly to a physical computer port, which is typically either a universal serial bus (USB) or a parallel port. Installing a locally attached printer provides the hosting system with the ability to process print jobs through its logical printer. The host system can be transformed into a print server by sharing the printer with other users on the network. This allows the host to process other print jobs sent to it from other computers and send them to the print device attached to it.
Network attached printers contain a network adapter or connect to a hardware print server that manage them. The HP Jet Direct print server is one common device for connecting parallel port printers to a network. Print servers are available for connecting printers to wired or wireless networks and most current models support USB.
How To Share A Printer Over A Network
Options for Deploying Logical Printers
When deciding how to deploy the logical printers, you should consider your network environment. If your network is a small one or a server is not available to host a logical printer, you can create a logical printer on each computer that needs access to a print device. For most networks, you should choose a server to act as your print server. Windows Server 2008 provides a role called Print Server that allows administrators to manage multiple printers on one machine. Although Print Server is not resource extensive, it may be wise to choose a server that hosts services and applications that require large amounts of server space, such as Microsoft Structured Query Language Server.
Deploying Network Attached Printers
In a Windows environment, local printers can be deployed using Control Panel. However, in Windows Server 2008, you have to install Print Services through Server Manager or through the command line. This role includes the Print Server service, Line Printer Daemon service, and Internet printing service.
Of these three services, only Print Server is required when installing the Print Services role. The PMC is also installed on Full versions of Windows Server 2008 and allows you to manage local and remote print servers. When you share a printer or a file, Windows enables the File and Printer Sharing exception in Windows Firewall with Advanced Security.
The Line Printer Daemon (LPD) service allows computers that use the Line Printer Remote (LPR) service to access shared printers. This includes UNIX-based client computers. When you install the LPD service, the Transmission Control Protocol/Internet Protocol Print Server (LPDSVC) service is started and Windows Firewall creates an exception for port 515. If your Windows clients print to a UNIX print server that uses the LPD protocol. To support this in Windows Server 2008, you need to install the Line Printer Remote (LPR) Port Monitor on the client. You can do this through the Add Features menu or by typing this command in the command line:
servermanagercmd.exe -install start LPR-Port-Monitor
The Internet Printing role service creates a website that hosts printers. This site is built on the Internet Information Services (IIS) 7.0 platform and allows users to add printers to their clients and manage the printers on the print server. The default Web site location is http://servername/printers, where servername is the name of your print server. Clients use this URL to add printers that their local machine can use. To support this feature, they must install the Internet printing client.
Because Internet printing relies on IIS 7.0 components, it cannot be installed on servers running Windows Server 2008 Server Core. If the IIS roles you need are not installed, you will be prompted to install them with the role service.
Printer Pools
Printer pools are an excellent option in cases where more than one print device is needed to handle multiple or large print jobs. Rather than requiring users to remember to add and use a second printer, a printer pool is a single printer that sends jobs to multiple print devices. (Remember, the printer is the logical device on a computer and the print device is the actual hardware.) This helps spread out the work load to make printing more efficient.
Requirements for a printer pool include:
- Two or more printers that can use the same printer driver. Windows Server 2008 does not support a printer that requires multiple printer drivers.
- The printers should be located relatively close to each other. If a company is relatively large, it would annoy employees to have to walk to the other side of the building to retrieve a print job, even if they know which printer is handling their job.
A Few Good Printers
