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RE: Link Status thoughts




Pat,

Thanks for the answers.
One more question to complete the picture.
What should the XGXS transmit onto the XAUI interface when the link is down
- the regular data stream, or idle patterns (or other)?

By the way - if /E/ can be transmitted into the XAUI/PCS, then Figure 48-8
should include this case, and hence, the relevant state machine diagrams.

Regards,
Lior.

~~~~~~~~~~~~~~~~~~~
Lior Re'em
Avaya Inc.
Israel

Tel :  +972 3 6457608
Email : lreem@avaya.com
~~~~~~~~~~~~~~~~~~~

> -----Original Message-----
> From:	THALER,PAT (A-Roseville,ex1) [SMTP:pat_thaler@agilent.com]
> Sent:	&dalet; &nun;&vav;&bet;&mem;&bet;&resh; 01 2000 2:03
> To:	Lior Reem; 'rtaborek@earthlink.net'
> Cc:	'HSSG'
> Subject:	RE: Link Status thoughts
> 
> 
> Lior,
> 
> /E/ would normally be transmitted when any of the physical sublayers (e.g.
> a PCS or an XGXS) receives bytes that it cannot encode. For instance, if
> a DTE XGXS got a byte from the XGMII that was a control byte but did not
> have a valid control code or if the 10GBASE-X PCS received a byte that
> had a code violation. They are normally caused by bit errors. 
> 
> Also, if a sublayer receives an /E/, it will transmit an /E/. 
> 
> The purpose of /E/ is to protect against an error getting turned into
> a valid code that might end up producing a packet with an undetectable
> error.
> 
> There are two proposals for break link and remote fault siganlling. The
> 802.3ae task force has not made any decision on the matter yet. By the
> way,
> since
> we have an approved project, the group is no longer called HSSG, High
> Speed Study Group. A study group exists to study what project if any
> should be initiated. Once the project is approved, it isn't a study 
> group any more.
> 
> 802.3ae has not adopted any objectives for any kind of auto negotiation
> protocol. All the links we have defined will initialize using the 
> normal data signals -- no training signals are needed.
> 
> Pat Thaler
> 
> -----Original Message-----
> From: Lior Reem [mailto:LReem@avaya.com]
> Sent: Monday, October 30, 2000 7:23 AM
> To: 'rtaborek@earthlink.net'
> Cc: 'HSSG'
> Subject: RE: Link Status thoughts
> 
> 
> 
> Hi Rich,
> 
> 1. Can you explain in which cases /E/ is transmitted onto the XAUI
> interface, and how should the receiver react in these cases?
> 2. Are there any agreements in the HSSG about Remote Fault and Break Link
> signaling?
> 3. Any thoughts about Link Initialization?
> 
> These questions are mainly a concern for cross-connect equipment which
> work
> in low levels, but need to supply solutions in broken link cases.
> 
> Thanks,
> Lior.
> 
> 
> ~~~~~~~~~~~~~~~~~~
> Lior Re'em
> Avaya Inc.
> Israel
> 
> Tel :  +972 3 6457608
> Email : lreem@avaya.com
> ~~~~~~~~~~~~~~~~~~
> 
> > -----Original Message-----
> > From:	Rich Taborek [SMTP:rtaborek@earthlink.net]
> > Sent:	ℷ &alef;&vav;&qof;&tet;&vav;&bet;&resh; 31 2000 10:53
> > To:	HSSG
> > Subject:	Re: Link Status thoughts
> > 
> > 
> > Isaac,
> > 
> > P802.3ae has no Auto-Negotiation objective and Auto-Negotiation was
> > voted down at the September, 2000 meeting. Current P802.3ae definitions
> > set Link Status = OK when the transmitter is operational and the
> > receiver can synchronize to the incoming bit stream and signal detect is
> > OK. Any "close loop" or handshaking of the two simplex links must be
> > initiated at the MAC level or above. This is true for all P802.3ae
> > variants including LAN and WAN and is independent of coding and the
> > presence or absence of any interfaces or extensions.
> > 
> > Best Regards,
> > Rich
> >      
> > --
> > 
> > Isaac Fuchs wrote:
> > > 
> > > Hi Rich
> > > As I know from 802.3z  link_status is a close loop
> > > information. It's mean that link_status is up only when
> > > both sides transmit and also receive  right symbols (c1,c2)
> > > [I know that 802.3z includes also auto_neg.].
> > > Is there  in P802.3ae any close loop (LAN application)?
> > > I mean  when I transmit after powering on /K/R/.. from XGXS layer how
> > can I
> > > know that the remote receive this information?
> > > Regards
> > > Isaac Fuchs
> >                                  
> > ------------------------------------------------------- 
> > Richard Taborek Sr.                 Phone: 408-845-6102       
> > Chief Technology Officer             Cell: 408-832-3957
> > nSerial Corporation                   Fax: 408-845-6114
> > 2500-5 Augustine Dr.        mailto:rtaborek@nSerial.com
> > Santa Clara, CA 95054            http://www.nSerial.com