Subject: iSCSI: immediate vs. unsolicited

From: "Eddy Quicksall" <[email-masked]>
Date: Fri, 8 Jun 2001 10:50:25 -0400

I see a semantic problem with the use of immediate being a subset of
unsolicited. Being a subset, one can't use the word "unsolicited" by itself
to mean "without the use of R2T" and some confusion is inevitable.
I would like to propose a wording standardization of immediate data vs.
unsolicited data.

If we could use "immediate data" to mean data accompanying a command PDU and
"unsolicited data" meaning data-out PDU’s that are not solicited with an
R2T, that would be a great help.

If this seems like a good idea, I will be happy to go through and find all
references to "immediate" and "unsolicited" and make suggested wording
changes.

Here is an example:

Section:
      1.2.5 iSCSI Full Feature Phase

Current:
   Outgoing SCSI data (initiator to target user data or command
   parameters) is sent as either solicited data or unsolicited data.
   Solicited data is sent in response to Ready To Transfer (R2T) PDUs.
   Unsolicited data can be sent as part of an iSCSI command PDU
   ("immediate data") or in separate iSCSI data PDUs.  An initiator may
   send unsolicited data either as immediate (up to the negotiated
   maximum PDU size) or in a separate PDU sequence (up to the negotiated
   limit)).

   Targets operate in either solicited (R2T) data mode or unsolicited
   (non R2T) data mode.  In unsolicited mode, an initial R2T is implied.
   A target MAY separately enable immediate data without enabling the
   more general (separate data PDUs) form of unsolicited data.

Proposed:
   Outgoing SCSI data (initiator to target user data or command parameters)
   is sent as either immediate data, solicited data or unsolicited data.
   Immediate data is sent (up to the negotiated maximum PDU size) as part
   of an iSCSI command PDU ("immediate data"). Unsolicited data is sent
   in separate iSCSI data PDUs (up to the negotiated limit). Solicited
   data is sent in response to Ready To Transfer (R2T) PDUs.

   In unsolicited mode, an initial R2T is implied. A target MAY separately
   enable immediate data without enabling the unsolicited data.

mailto:[email-masked]

mailto:[email-masked]

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From: "BURBRIDGE,MATTHEW (HP-UnitedKingdom,ex2)" <[email-masked]>
Date: Fri, 8 Jun 2001 17:30:22 +0100

Hi Eddy

This certainly gets my vote!

Matthew

-----Original Message-----
From: Eddy Quicksall [mailto:[email-masked]]
Sent: Friday, June 08, 2001 3:50 PM
To: [email-masked]
Subject: iSCSI: immediate vs. unsolicited

If we could use "immediate data" to mean data accompanying a command PDU and
"unsolicited data" meaning data-out PDU's that are not solicited with an
R2T, that would be a great help.

Here is an example:

Section:

Current:

Proposed: