The CUPS Connector makes CUPS printers (printers installed on a Linux/Unix/OS X server/workstation) available to Google Cloud Print clients, like ChromeOS.
The CUPS Connector has two modes, it runs in one or both:
- cloud: (1) the client gives a new print job to Google's servers via the Internet, then (2) Google's servers give the job to the CUPS Connector via the Internet, then (3) the CUPS Connector gives the job to a CUPS server (usually localhost:631)
- local: (1) the client gives a new print job to the CUPS Connector via the local subnet, then (2) see (3) above
Local mode is also called GCP 2.0, or Privet in the developer docs. You can learn the technical details here:
A printer that supports Privet *can* depend on Google's servers, via the Internet, for adjustments like format conversion and scaling, if the printer has too little resources.
The CUPS Connector *never* contacts Google's servers in local mode. Since the CUPS Connector depends on CUPS, all scaling and format conversion can be handled within CUPS. This has three benefits: (1) privacy-sensitive customers like yourself, (2) performance can be improved, or at least better controlled, (3) flakey/slow/third-world Internet connections don't affect printing.