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Error handling in 64/66: Was Re: (Another) Question Regarding Open-Loop

>Yes you're right, I must have been looking at an older slide deck. But
>now that I see the new TX process and RX process, I have another
>question. If you allow for the sequence TZZZZZZZ ZZZZSDDD, what happens
>if you get an error somewhere. It would appear as if the condition to
>get out of the error state is to wait for ZZZZZZZZ, but this won't
>appear between frames given the above circumstance and the next frame
>will also be "errored". Perhaps I'm mistaken, but it would seem as if
>the next perfectly good frame will be trashed? Is this correct?

Dave, Your observation is correct. The way the state m/c is right
now, if there is a error, it doesnt get out of the E state till
a clean Z frame. A problem with this is if you have back to back
packets with min IPG spacing, you might end up with a S frame
immediately following a T frame and there wont be any intermediate
Z frame for a while.

We probably should modify the state diagram by allowing transitions
from E state to Z, D, or T states. (We need to disallow transition
from E to S to prevent a certain 3-bit error condition from
slipping through).

Birdy Amrutur