In https://lists.debian.org/debian-printing/2016/12/msg00089.html
Till Kamppeter wrote > So if you really want to have a Brother printer, make sure that > it does IPP Everywhere or AirPrint. These are driverless printing > methods which are in Ubuntu from version 17.04 (Zesty) on and > they are also in current Debian Experimental. We are looking at fairly recent printers, of course, and choosing one with AirPrint is not hard. There will probably be a logo on the box and the specifications will advertise AirPrint as a language or under "mobile printing". But what about IPP Everywhere? How is a user easily to know the printer is capable of it? Looking at the specifications for the ones listed at www.pwg.org (the DesignJet T830, for example) I can see nothing which indicates PWG raster is supported. Then there is the matter of whether a printer which does support PWG raster is an IPP Everywhere printer. Apparently the Lexmark CS720de understands PWG raster (https://github.com/apple/cups/issues/4932), but does this make it an IPP Everywhere printer? On the other hand, it seems that a PDL key with "image/urf" means it is (almost?) certainly an AirPrint printer. Or does it matter when it comes to driverless methods if "image/pwg-raster" in the PDL is equated with "IPP Everywhere"? A user can always use avahi-browse to get the printer's capabilities but this is an after the event method. Some vendors do specfify PWG in their literature but many don't, even when it is present. -- Brian.
