SYM-019-a:
The 4.2.21.5 Keyless copy section should
identify How an application client determines that a Logical Unit has the
capability to act as a KCSLU or a KCDLU
There is no bit anywhere that indicates
the support for acting as a KCSLU or KCDLU. In reality, it is if
the LU supports the EXTERNAL encryption mode or the RAW decryption mode.
So the request here should be reworded to say how does an application
client determine which settings of "ENCRYPTION MODE" and "DECRYPTION
MODE" fields are supported.
Looking at the section describing each
of these fields, there is no text describing a CC returned for RAW or EXTERNAL
if they are not supported. The standard is silent. This is
also the case for DISABLE. Obviously the standard does not explicitly
indicate anywhere that these modes are optional.
What should we do?
Option 1: Add text under the description
of these fields stating that if EXTERNAL or RAW mode is selected and it
is not supported then CC. This would change the standard to explicitly
state that these options are optional.
Option 2: Add text somewhere to mandate
support for these modes. I suspect this option is not desired.
I think that we must do either option
1 or option 2. The standard needs to be clear if these are optional
or not.
If we go done the path that these are
explicitly stated as optional, then this letter ballot comment leads to
the question, "How do we report support for different values in these
two fields?" This is not just a question of Keyless copy but
also of MIXED decryption mode. There is an implication that ENCRYPT
and DECRYPT are supported as well as DISABLE. I am not sure that
is correct. There could be a device that only supportes one or the
other or some combinations.
Comments?
Kevin D. Butt
SCSI & Fibre Channel Architect, Tape Firmware
MS 6TYA, 9000 S. Rita Rd., Tucson, AZ 85744
Tel: 520-799-2869 / 520-799-5280
Fax: 520-799-2723 (T/L:321)
Email address: kdbutt@us.ibm.com
http://www-03.ibm.com/servers/storage/