RE: iSCSI question

[Shahram Davari <Shahram_Davari@pmc-sierra.com>]

I think I figured out were the problem (confusion) is.

1) Section 5.14 (recover classes) states:

"  The recovery scenarios detailed in the rest of this section are rep-
   resentative rather than exclusive. In every case, they detail the 
   lowest class recovery that MAY be attempted. The implementer is left 
   to decide under which circumstances to escalate to the next recovery 
   class and/or what recovery classes to implement."


2) However, section 5.5 says:

"      a) Each level is a superset of the capabilities of the previous 
      level. For example, Level 1 support implies supporting all capa-
      bilities of Level 0 and more. "


This means that section 5.14, considers the recovery classes as disjoint,
and permits escalating to higher level classes when needed, while setion 5.5 considers each class to be a superset/subset of another class. 

Which one is correct?

Yours,
-Shahram


> -----Original Message-----
> From: Shahram Davari 
> Sent: Thursday, August 08, 2002 4:21 PM
> To: 'Bill Studenmund'
> Cc: 'pat_thaler@agilent.com'; Julian_Satran@il.ibm.com; 
> ips@ece.cmu.edu;
> owner-ips@ece.cmu.edu
> Subject: RE: iSCSI question
> 
> 
> Hi Bill,
> 
> Thanks for your reply. Please see my comments below:
> 
> 1) I doubt that the session re-establishment code is simpler 
> than PDU recovery code.
> But think what you are saying is that, you need to have the 
> session recovery anyway, so the PDU recovery is extra code.
> 2) Even if that is the case, it has nothing to do with the 
> error recovery hierarchy.
> The error recovery hierarchy must show what recovery should 
> be tried before the other ones. In other words it has to show 
> how the recovery escalates.
> 3) I think it should escalate as following: PDU -> Connection 
> -> Session
> 
> 
> Yours,
> -Shahram  
> 
> > -----Original Message-----
> > From: Bill Studenmund [mailto:wrstuden@wasabisystems.com]
> > Sent: Thursday, August 08, 2002 3:59 PM
> > To: Shahram Davari
> > Cc: 'pat_thaler@agilent.com'; Julian_Satran@il.ibm.com; 
> > ips@ece.cmu.edu;
> > owner-ips@ece.cmu.edu
> > Subject: RE: iSCSI question
> > 
> > 
> > On Thu, 8 Aug 2002, Shahram Davari wrote:
> > 
> > > Pat,
> > >
> > 
> > > Thanks. I understand your point. Although terminating a 
> > session may be
> > > easy, but, starting a new session requires new login, parameter
> > > exchange, new connections establishment, authentication, etc. So I
> > > wonder how is this any simpler than a simple PDU retransmit?
> > 
> > It's simpler in terms of the code in both the initiator and target.
> > 
> > That's how it's simpler. :-)
> > 
> > Take care,
> > 
> > Bill
> > 
>