P1394> Interim PPDT Draft

P1394> Interim PPDT Draft

PJohansson at aol.com PJohansson at aol.com
Fri Dec 3 01:07:23 EST 1999


In a message dated 99-11-25 10:15:33 EST, shimura at pure.cpdc.canon.co.jp 
writes:

<<I agree that utility of the current "function" definition has been lost, 
and the definition should be removed.>>

The easiest part of the problem, upon which I think we all agree...

<<Though I agree to remove the definition, I think replacing the "function" 
with the "unit architecture" is too restrictive because definition of the 
"unit architecture" seems to imply that function (or a set of services) 
resides only in the target.>>

<<One of the original intent for the "function" would be to define a set of 
services provided over single login by a device (either initiator or target). 
In this sense, there will be no difference between "function" on the 
initiator and "function" on the target because PPDT provides symmetric 
transport service, though current definition only supports the "function" 
resided in the target.>>

An insightful observation, which unfortunately opens a Pandora's box of 
connected problems. I agree that this needs to be resolved; for example, 
"logical unit" is used in many places where reference to an initiator would 
be equally appropriate.

Would "peer unit" be a useful technical term? A peer unit would be either an 
initiator or a logical unit. I'm very open to other suggestions, too.

<<I've created a text for removal of the "function" definition and symmetric 
description at places referring the "function". Please find attached 
document(RMFUNCr01.pdf).>>

I think it's a step in the right direction, but I have some problems with the 
details. The more I look at the issues, the more the seem embedded in the 
current draft. Some of them are substantive, not just editorial. For example, 
has the working group made a considered decision about how a PPDT initiator 
is identified from configuration ROM? Or just pushed it off as a low priority 
matter because most are concentrating on implementations that aren't so 
symmetric? I think we can resolve this in Los Angeles, perhaps with some 
reflector discussion before hand.

<<In this document, I've also removed "management service" definition because 
it was referred only once in the description of the bi-directional blocking 
connection as an example.>>

I think it would be better to keep the definition, but fix it to reference 
"peer units" or some similar term.

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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