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Re: headless chicken


Thank you for the information of the Isolate bit.  It is really 
helpful for me to learn about the essence behind the Ethernet 
standard document.

At 5:26 PM -0700 00.6.23, Howard Frazier wrote:
> I continue to be concerned about the proposals for using LSS for this
> function.  I believe that LSS is several times more complicated than
> what we need for this function, and that like the RF bit in 
> gigabit ethernet, we will wind up with a broken specification that
> does not support interoperability.

The function of LSS is just advertising the local management register 
information periodically to its link partner by using InterPacket Gap 
period including continuous idle stream.  I believe it is simple and 
reliable enough as far as its function/protocol are concerned.  Please 
refer to my recent reflector note to Rich:

For the Link Status code for advertising RemoteFault and BreakLink, 
we will adopt 4-bit Hamming protection and hence we do not need any 
state machine for its detection.  If we detect RemoteFault then 
we simply rewrite the Status Register bit for the remote state.  
If we detect no-RemoteFault then simply rewrite the register.
(Note that the register might have to be latched until read by MAC 
but this is another issue.)  We do NOT need to consider any 
periodicity at its detection.

With 4-bit Hamming Protection, the wrong RemoteFault detection 
probability is extremely low; once every 3,058 years even at 
BER 10^-4.  It reaches once every 7x10^19 years at 10^-8....

As for interoperability issues, I am not sure I understand the 
broken specs issue in GbE RF bit.  Would you please elaborate 
your concern?

Best Regards,

NTT Network Innovation Laboratories
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