Security Protocol Out/Request volume Element Address

Ralph Weber roweber at
Thu Mar 30 11:56:13 PST 2006

* From the T10 Reflector (t10 at, posted by:
* Ralph Weber <roweber at>
I had thought the best possible compromise had been applied
in the selection of the Security Protocol Out command operation
code. The current choice is not the first mistake I have ever
made, nor will it be the last.
I am certain CAP will give proper consideration to any written
proposal to change the operation code. A few cautionary notes
seem worthwhile.
Every revision of SPC contains a table listing operation codes
in numerical order. It is a virtual certainty that CAP will
consult this table when considering operation code assignment
The operation code for a command whose CDB length is 12 bytes
(such as Security Protocol Out) must be between A0h and BFh.
Happy hunting!
David Peterson wrote:
> I agree with Kevin, assuming an SMC device will not use Security 
> Protocol Out is a bad assumption...Dave 
> (no disclaimer)
>     *From:* owner-t10 at [mailto:owner-t10 at] *On Behalf Of
>     *Kevin D Butt
>     *Sent:* Wednesday, March 29, 2006 12:54 PM
>     *To:* t10 at
>     *Subject:* Security Protocol Out/Request volume Element Address
>     I just noticed that the new Security Protocol Out command collides
>     with the op code for an SMC device (Request Volume Element
>     Address).  I thought a free op code was requested.  This means
>     that Automation devices will never be able to use any of the
>     security protocols.  I think this is a bad idea.	I don't know
>     where how all the library vendors missed this.  Can this be changed?
>     Thanks,
>     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 at
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