Apple has prototyped all of the required attributes, operations, and values in the following prototype draft of IPP Shared Infrastructure Extensions:
1. During implementation, it was difficult to make sure that I had implemented all of the required attributes. I ended up making a list of the required attributes, which should be included in the specification.
2. There is no way to provide resource files - icons, ICC profiles, etc. This could be done with a few new attributes provided by the Infrastructure Printer with support for the HTTP PUT and DELETE requests:
a. “printer-resource-directory-uri (uri)” - specifies a HTTP or HTTPS URI that can be used to upload resource files using PUT requests or delete resource files using DELETE requests
b. “printer-resource-k-octets-available (integer(0:MAX))” - specifies resource storage availability
c. “printer-resource-k-octets-used (integer(0:MAX))” - specifies kilobytes of resources that have been used
i. HTTP authentication can limit to proxy user, but how to limit to output devices that have been registered?
ii. Also, for fan-out how to avoid/prevent name collisions? Provide separate “printer-resource-directory-uri” values, filtered on “output-device-uuid”?
3. There is no way to do registration, but our implementation works with a printer-uri that is obtained separately
a. Output Device is “registered” by using the Update-Output-Device-Attributes operation
4. There is no way to do de-registration
a. This is more of an issue for fan-out configurations - no way to remove an output device from the Infrastructure Printer
b. We ended up adding a Deregister-Output-Device operation corresponding to the existing Cloud Imaging Model DeregisterSystem operation
Michael Sweet, Senior Printing System Engineer, PWG Chair