Kevin,
 
We need to make a decision on this one because there is no obvious
right answer.  IETF uses separate SPIs (what T10 calls SAIs) for
IKEv2 and ESP - 8 bytes SPIs are used for IKEv2, but ESP uses 4 byte
SPIs.  SCSI is using the same SPI for both purposes, and hence needs
to pick one length - I agree with your suggestion that 8 bytes (as
used in IKEv2-SCSI) is preferable.  >From an implementation standpoint
this would reduce the impact on reuse of the more complex IKEv2
implementations (more complex is by comparison to ESP).
 
Thanks,
--David
----------------------------------------------------
David L. Black, Distinguished Engineer
EMC Corporation, 176 South St., Hopkinton, MA  01748
+1 (508) 293-7953             FAX: +1 (508) 293-7786
black_david@emc.com        Mobile: +1 (978) 394-7754
----------------------------------------------------




From: Kevin D Butt [mailto:kdbutt@us.ibm.com]
Sent: Friday, December 21, 2007 11:24 AM
To: roweber@ieee.org; Black, David; matt.ball@ieee.org
Cc: t10@t10.org
Subject: DS_SAI length conflict between 07-437r4 and 07-169 & SPC-4


Ralph, David, and Matt,

All the DS_SAI values in the ESP-SCSI (07-169r5) (e.g., Table x3 — ESP-SCSI data-out buffer parameter list descriptor without initialization vector) are shown as 4-byte values as they are in SPC-4 Table 44 — Minimum SA parameters.  However 07-437r4 shows them as 8-byte values.  I think 07-437r4 is correct and SPC-4 and 07-169 need to be modified to match.

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@us.ibm.com
http://www-03.ibm.com/servers/storage/