Re: iSCSI : On the subject of R2T and Task Tags.

[Matt Wakeley <matt_wakeley@agilent.com>]

Pierre Labat wrote:

> I agree that the draft must not impose to the target to have a different tag
> for each R2T (it is up to the target implementation to decide).  I disagree
> to impose a unique target tag for the whole IO.  It imposes the target to do
> score boarding
> to know when all the data have been received. Letting the possiblility to the
> target
> to have one tag per R2T (or add a subtag identifying the R2T as proposed Santosh)
> 
> allows the target to dispense with the score boarding. The target knows that all
> the
> data has been received when a data PDU with the "F" bit set has been received
> for each R2T.

There is no need to do scoreboarding.  Just count the number of bytes
received.  If they all add up, then you've received all the data.  I for one
would not rely on a PDU with the "F" bit set.  I would want to cross check it
with the correct number of bytes.


> 
> Regards,
> 
> Pierre
> 
> >
> >
-Matt Wakeley
Agilent Technologies