RE: Regarding CSG and NSG

Matthew,

Yes I am setting the T bit to 1, and CSG = 0 and NSG = 1 in my login response.

But the initiator seems to drop the connection and trying to set up a new connection.

The following is the complete procedure,

Should I set the the T = 0, CSG = 1, NSG = x ?

-- Sajjan

-----Original Message-----
From: BURBRIDGE,MATTHEW (HP-UnitedKingdom,ex2) [mailto:matthew_burbridge@hp.com]
Sent: Thursday, July 25, 2002 1:53 PM
To: 'Rao, Sajjan'; ips@ece.cmu.edu
Subject: RE: Regarding CSG and NSG

Sajjan,

It depends whether the initiator has its T bit set. If T=0 then the initiator is saying that it is security phase and is not yet ready to move to the next phase (NSG=ignore: if T=0, NSG is reserved). This implies that it does want to negotiate security (i.e. authentication). If T=1, it says that is has no more security to negotiate and is ready to move to operational phase (as NSG=1) when the target says it's ready. In the latter of these two options (T=1,CSG=0,NSG=1) then the initiator is giving the target chance to start authentication.

Alternatively, if the initiator does not want to negotiate security it can set CSG=1 in the initial login. This removes one message exchange if the target does not want to negotiate security but runs the risk of receiving a login failure if the target does want to negotiate security. If it wants to negotiate parameters then: T=0,CSG=1,NSG=reserved. If it does not want to negotiate text parameters then T=1, CSG=1, NSG=3.

In your example I am presuming that T=1 in 1). which is fine. Initiator is giving the target the opportunity to negotiate security but does not wish to start it itself. In 2), the T bit MUST be 0 as it can not be the final login response. The target is informing the initiator that it is happy to enter operational phase (CSG=1). As the T bit must be 0 in 2) NSG = reserved.

1) Suppose the initiator sets T=1, CSG = 0 and NSG = 1 in login request, and says requires no authentication.

2) Can the target set the CSG = 1 and NSG = full feature phase, in its login response? NO

It should be

2) Can the target set the T=0, CSG = 1 and NSG = reserved, in its login response?

Matthew Burbridge
Principal Engineer
Nearline NSS Bristol

Hewlett Packard
Tel: +44 117 312 7010
E-mail: matthewb@bri.hp.com

-----Original Message-----
From: Rao, Sajjan [mailto:sajjan_rao@adaptec.com]
Sent: Thursday, July 25, 2002 5:53 AM
To: ips@ece.cmu.edu
Subject: Regarding CSG and NSG

Hi,

I have a couple of questions.

1) Suppose the initiator sets CSG = 0 and NSG = 1 in login request, and says requires no authentication.

2) Can the target set the CSG = 1 and NSG = full feature phase, in its login response?

Sajjan