The issue is:
28) ISSUE: What if compression is supplied but not supported?
Possible Alternatives (related to Issues 3 and 6): OPEN - propose to the DL
that "compression" is REQUIRED for IPP/1.1 (with at least the 'none' value),
even though it is OPTIONAL for IPP/1.0.
We propose that 'compression' be required like 'document-format' even if the
only value supported is none because both the compression and the
document-format for a document must be supported by the printer in order for
the document to be processed and printed. The lack of mandated supported
for 'compression' in a printer is a bug in IPP/1.0 and this bug means that a
printer which doesn't support the compression attribute (and ignores it per
IPP rules) may try to process a document that is compressed and therefore
unreadable.
By requiring that a printer support the compression operation attribute, we
must also require support for the 'compression-supported' printer attribute
and we must add 'compression-supported' to the SLP printer template.