RE: FCIP Last Call, comment 109 - Special Frame

[Black_David@emc.com]

> Regarding:
> 
> > Comment 109: The proposed resolution says:
> >
> >    The SF is protected by requiring that the echoed data field values
> >    exactly match those sent. This is an end-to-end-to-end check that
> >    is more certain than even a CRC.
> >
> >         Unfortunately, comments 52 and 53 call out text that allows
those
> >         fields to be changed.  This needs some more thought/explanation,
> >         and this issue needs to be considered open for now.
> 
> Yes, the fields are allowed to be changed and such changes result
> in the connection being closed 100% of the time. Whether the changes
> are intentional or accidental, the connection is ALWAYS closed if
> the SF fails to transit back and forth unchanged.
> 
> The ONLY way the connection is NOT closed is when the SF transits
> both directions unchanged, NO EXCEPTIONS.
> 
> I believe that this fully maintains the integrity of the end-to-end
> check described in the comment response.

That would be fine if the received data were always discarded when
a change occurred that caused connection closure.  My understanding
of the "poor man's SLP" scenario is that the received data is intended
to be used even though the connection was closed.  TCP-grade data
integrity may be ok for that use - if that's the case, a single
sentence saying that as part of the new description of "poor man's
SLP" should be sufficient to close this issue.

Thanks,
--David
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