CUPS provides a portable printing layer for UNIX-based operatingsystems. It has been developed by Easy Software Products to promote astandard printing solution for all UNIX vendors and users. CUPS uses the Internet Printing Protocol ("IPP") as the basis formanaging print jobs and queues. The Line Printer Daemon ("LPD") ServerMessage Block ("SMB"), and AppSocket (a.k.a. JetDirect) protocols arealso supported with reduced functionality. CUPS adds network printerbrowsing and PostScript Printer Description ("PPD") based printingoptions to support real-world printing under UNIX.CUPS provides the System V and Berkeley command-line interfaces.CUPS also supports a customized version of GNU Ghostscript (currently basedoff GNU Ghostscript 5.50) and an image file RIP that are used to supportnon-PostScript printers. Sample drivers for HP and EPSON printers are includedthat use these filters. This software is available in the cups-pstorasterport.