SAS Near-end Analog Loopback 7.7.1.1

Elliott, Robert (Server Storage) Elliott at hp.com
Thu Jun 13 18:04:44 PDT 2002


* From the T10 Reflector (t10 at t10.org), posted by:
* "Elliott, Robert (Server Storage)" <Elliott at hp.com>
*

Initiators - Not mandatory.  How to invoke it is vendor-specific, so
there's no way to test whether it's supported.

Targets - Not mandatory - barely even allowed.  If an initiator
instructs a target with a single phy to enter near-end analog loopback
mode,  it can never wake it up again since the target is ignoring
further input.  The target won't do anything useful in this mode, since
it's only looping what it generates back to itself.  If it had frames to
send, it will detect unexpected frames and not be able to do anything
about them.  With a dual-phy target, you could at least turn the mode
off after doing this.

Expanders - Not mandatory.  An initiator can force NEA mode on a remote
phy that is part of an active connection, then send data patterns on
that connection (but not BREAK or CLOSE) and have them looped back.
 
--
Rob Elliott, elliott at hp.com
Industry Standard Server Storage Advanced Technology
Hewlett-Packard



> -----Original Message-----
> From: Cable, Andrew L [mailto:andrew.l.cable at intel.com] 
> Sent: Thursday, June 13, 2002 3:53 PM
> To: 't10 at t10.org'
> Subject: Near-end Analog Loopback 7.7.1.1
> 
> 
> * From the T10 Reflector (t10 at t10.org), posted by:
> * "Cable, Andrew L" <andrew.l.cable at intel.com>
> *
> 
> Allan/All,
> 
> The PHY Study group voted to eliminate any mandated 
> requirements for far-end retimed loopback at the Minneapolis 
> conference (section 7.7.1.2). Does the same relaxed 
> requirement apply for near-end analog loopback (Section 7.7.1.1)?
> 
> 
> If near-end analog loopback is mandatory, does it apply to 
> all initiators, expanders and targets?  
> 
> 
> 
> 
> Thanks.
> 
> Andrew.
> 
> 
> 
> 
> 
> Andrew Cable
> Intel Corporation
> P: (480) 554-9446
> andrew.l.cable at intel.com
> *
> * For T10 Reflector information, send a message with
> * 'info t10' (no quotes) in the message body to majordomo at t10.org
> 
*
* For T10 Reflector information, send a message with
* 'info t10' (no quotes) in the message body to majordomo at t10.org




More information about the T10 mailing list