Subject: [IPP] Prototype experience for IPP Shared Infrastructure Extensions

From: Michael Sweet <[email-masked]>
Date: Mon, 03 Nov 2014 07:42:18 -0500

Apple has prototyped all of the required attributes, operations, and values in the following prototype draft of IPP Shared Infrastructure Extensions:

    http://ftp.pwg.org/pub/pwg/ipp/wd/wd-ippsix10-20140226-rev.pdf

Comments:

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
   d. Issues:
      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

_______________________________________________
ipp mailing list
[email-masked]
https://www.pwg.org/mailman/listinfo/ipp