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
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
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