Re: iSCSI: Session Partial Resolution

["John Hufferd/San Jose/IBM" <hufferd@us.ibm.com>]

David,
I had thought that we had "agreed" (perhaps an overstatement) that a two
connection per session (Asymmetric Session) solved a number of problems,
one of which was brought up by Costa.  This would still fit the other stuff
you said.  Note: I did not say that we had consensus of using Asymmetric vs
Symmetric, just that an Asymmetric Session (of at least two connections)
solved some potential problems.  Also this did not say anything about
having the double Connections within a Session being on different NICs.
The value of at least two connections seemed to have value (solved certain
problems) even within a single NIC.

.
.
.
John L. Hufferd



meth@il.ibm.com@ece.cmu.edu on 09/20/2000 03:01:48 AM

Sent by:  owner-ips@ece.cmu.edu


To:   Black_David@emc.com, ips@ece.cmu.edu
cc:
Subject:  Re: iSCSI: Session Partial Resolution





David,

If we eliminate all support for multiple connections from the next version
of the draft and have a separate draft for multiple connections, then we'll
eventually end up with 2 different (incompatible) protocols. Depending on
whether we have a single connection or multiple connections, the initiator
and target will have to implement one or the other or both protocols. Some
products that implement only one version will not be compatible with other
products, etc, and we will have shot ourselves in the foot. The wide
acceptance of iSCSI will be strongly influenced by the ability to
inter-operate with all kinds of devices and products, many of which will
greatly benefit from one of the various multiple-connection models.

I recommend to try to focus on the question of the multiple-connection
model to see if we can at least agree that one or more of them sufficiently
satisfies the requirements, and then choose one of the satisfactory models.
Even if we can't agree on which model is the best, I think we can
more-or-less agree on which of the models is at least good enough.

- Kalman Meth


Black_David@emc.com on 19/09/2000 22:22:20

Please respond to Black_David@emc.com

To:   John Hufferd/San Jose/IBM@IBMUS, Black_David@emc.com
cc:   ips@ece.cmu.edu (bcc: Kalman Meth/Haifa/IBM)
Subject:  iSCSI: Session Partial Resolution





<... deleted ...>

OTOH, I do not see consensus on the session model for
multiple connection sessions among the Asymmetric model,
the Symmetric model, and Pierre Labat's proposal.  In
order to make progress on iSCSI, I see no alternative to
separating multi-connection sessions from the main iSCSI
spec.  Significant effort and email traffic has been
invested in this topic for at least 6 weeks and the issue
is not settled -- I don't think holding up the iSCSI spec
for another 6+ weeks in hopes of settling this issue on
the list is an effective way to make progress, but I'm
prepared to listen to dissenting opinions (e.g., if
someone thinks there is rough consensus, and I've missed
it); please send such opinions directly to me rather than
using the list.  I've already had one offline comment from
an outside observer expressing amazement at the willingness
of this community to discuss multi-connection sessions
"ad nauseum".

Therefore, I would ask that the authors of the next
version of the iSCSI draft delete all specification
of multiple connection sessions from the next version
of the except for a note that they will be handled in
a separate document.

<... deleted ...>

--David

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