Services for Macintosh
Services for Macintosh |
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With some AppleTalk networks, a condition known as LaserPrep Wars causes slow printing performance. Services for Macintosh solves this problem.
LaserPrep Wars occur when a network has Macintosh clients that use two or more versions of Chooser Packs (a collection of files, some of which contain PostScript information). When a Macintosh computer sends a print job to a PostScript printer, the printer uses a Chooser Pack to interpret PostScript commands in the print job, which include a PostScript preparation file (also called a LaserPrep file) and a PostScript driver. A printer can use only one version of the LaserPrep file at a time. When a Macintosh user sends a print job to the printer, the Macintosh checks for the printer's version of the LaserPrep file. If the printer currently has a different version than the Macintosh client uses, the Macintosh client sends its version of the LaserPrep file along with the print job and instructs the printer to load that file as the printer's resident LaserPrep file. Because Macintosh computers with different LaserPrep file versions send print jobs to a printer, different versions of the LaserPrep file are loaded and unloaded on the printer.
Performance problems arise because the printer must load and unload versions of the LaserPrep file and then print a startup page each time a different LaserPrep file becomes resident. This can also reduce the life cycle of the printer.
For example, suppose a Macintosh user whose client uses Chooser Pack version 6.0 sends a document to the printer. The LaserPrep version 6.0 file is made resident on the printer. Then, if the next document sent to the printer comes from a client that is using Chooser Pack version 7.0, the printer must reset, load LaserPrep 7.0, and print a new startup page before printing the document.
Services for Macintosh solves the LaserPrep Wars problem by sending the LaserPrep file with each job. This extra effort actually improves overall performance: the printer never has to spend time making a LaserPrep resident or printing a startup page.
For printers on an AppleTalk network, LaserPrep Wars are guaranteed to be avoided only if the printer is captured. If the printer is not captured, users who send print jobs directly to the printer, bypassing the print server, can initiate LaserPrep Wars.
LaserPrep Wars are always prevented when printers are attached directly to a computer that is running Windows 2000 Server that is set up with Services for Macintosh.