What are the differences between the Dispatcher queues (AppleTalk, Hotfolder, Named Pipe, EskoLink) and which one should be used?
EskoLink (Input Queue name = Esko Server)
You can find specific information about the different queues in the FlexRip manual, depending on the flavour: FlexRip Manuals.
The first three queues are part of the PostScript (PS) workflow. Files sent through these queues will be converted to PostScript, which means your job is flattened. Also, external references are not read but instead the internal preview is used (so sending Normalized PDF directly to a PostScript workflow will not give high-quality output).
From Suite 10 Assembly 6 onwards, the PS workflow is frozen. This means that there will no more be any development but only bug fixes.
AppleTalk protocol is no longer supported in Mac OS 10.6 (Snow Leopard) and in Windows 2008.
Named Pipe protocol is no longer supported since Window 2008.
The 4th queue EskoLink is a Direct Print Queue from the Automation Pilot or FlexRip Pilot for Esko native files.
You can choose to print to the FlexRip directly form Esko PrePress applications like PackEdge, ArtPro and DeskPack and all output options can be set interactively by using the Shuttle. To maximize throughput, operators can rip files via a ticket-driven workflow (Automation Engine Server or FlexRip Pilot), offline from the graphical editors. Jobs can be selected, assigned a ticket and then launched in the background, reducing workstation time. Users can see the ripping progress of any job on either the Mac or Windows PC. Logging information can be obtained.
So the EskoLink Queue (= Esko Server) is the preferred queue to be used.