P1394> Re: Feature Directory for an initiator?

P1394> Re: Feature Directory for an initiator?

PJohansson at aol.com PJohansson at aol.com
Tue Sep 28 01:47:49 EDT 1999


In a message dated 99-09-27 20:57:43 EDT, atsnaka at bsd.canon.co.jp writes:

<<Just for clarification...>>

More than just clarification, Ats---solid questions that aren't all resolved 
in my mind either.

<<Does this ("pinging" ) imply that either: ALL PPDT initiators have to 
support the message request/response mechanism, or ALL PPDT target have to 
implement some retry counter to abort the reverse login process?>>

My HUNCH is that it will be impossible to require ALL PPDT initiators to 
support MESSAGE_REQUEST and reverse login. I would prefer it if we could, but 
my suspicion is that some widely available desktop operataing systems won't 
have this functionality within the time frame we require. Perhaps someone in 
a better position to know could provide some solid answers.

EVEN IF all PPDT initiators implement MESSAGE_REQUEST, it is an essentially 
unconfirmed datagram service. It seems to me that targets will have to 
implement retry counters and timers to manage the reverse login process.

<<...may I ask what this NOP function does?>>

Nothing. The zero value was already reserved, never to be used. I suggested 
that we make it NOP, a fringe benefit that permits a target to determine that 
an initiator has reverse login support without actually requesting a LOGIN.

<<Are we still going to stick with a initiator not having a unit directory? 
Is the only way to discover a PPDT initiator is by the instance directory 
keyword?>>

I apologize if I have lost track of a working group decision; sometimes the 
minutes don't have as much detail as I would like.

I confess I am confused as to the current state of the working group opinion 
on this matter. Clearly a target has an instance directory (with keywords) 
that references one or more unit directories.

What DOES an initiator have? Nothing? An instance directory (as you suggest)? 
I think the current draft of PPDT is silent on this matter.

Regards,

Peter Johansson

Congruent Software, Inc.
98 Colorado Avenue
Berkeley, CA  94707

(510) 527-3926
(510) 527-3856 FAX

pjohansson at aol.com



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