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RE: Hari and train-up sequences

I know of no reason why training is required today on the Hari interface.

While there are functions / features that can be added which might require
such training, no one should assume that autonegotiation is needed in the
base proposal.


> -----Original Message-----
> From: Booth, Bradley [mailto:bradley.booth@xxxxxxxxx]
> Sent: Wednesday, November 17, 1999 11:59 AM
> To: HSSG
> Subject: RE: Hari and train-up sequences
> So, the auto-negotiation that you're proposing would be to 
> train the Hari
> interface and exchange link configuration information (such as pause
> capabilities).  This would be comparable to 802.3z use of the
> synchronization state machine (in Clause 36) to train the receive PMA
> service interface while exchanging link configuration information via
> auto-negotiation (in Clause 37).  The concern that I have is that each
> direction of the Hari interface (transmit and receive) needs 
> to be trained,
> which is different than what is done in 802.3z which only 
> trains the receive
> PMA service interface.
> To me, the training of the Hari interface sounds like it will be a
> requirement of that interface.  I do wonder why we need the 
> auto-negotiation
> to exchange link configuration information.  The only thing that I can
> foresee that a local device would have to negotiate with a 
> link partner is
> the pause capabilities, and even those could be subject to 
> debate.  So, if
> auto-negotiation is not required, then the only requirement 
> is to train the
> Hari interface.  The use of a management interface connection 
> into the PMD
> device (as per Howard Frazier's proposal) would assist in 
> determining the
> Hari interface's training status.
> Don't get me wrong, I'm not violently opposed to 
> auto-negotiation.  I wish
> only for someone to present to the HSSG what auto-negotiation 
> offers and the
> benefits of adding it to our standards work.  It's not one of our
> objectives, so I'd like to know why we should spend time on it.
> Thanks,
> Brad