Re: [PWE3] draft-manhoudt-pwe3-tsop-00.txt and IP

[Yaakov Stein <[e-mail]>]

Gert and all, 

I would like to partially retract what I previously said about the S1 byte and traceability.
I hit the send too quickly, and should have thought over the issue first.

It is true that the SSM message relates information about traceability,
i.e., that after N SDH network elements a certain amount of phase noise has accumulated,
so that the bit stream does not obey the G.81x masks.
However, this is not applicable here.
Here the physical layer traceability is truly broken,
and you are relying on unexplained magic to restore it.

All that your statement about not dropping or adding bits guarantees is
lim_tau->infinity  MTIE(tau) / tau = 0, which is not enough.
The MTIE slope has to obey the constraint at some finite time.

Put in another way, stating that you don't drop or add bits is equivalent
to stating that you are somehow traceable to the original clock,
but since you broke the physical layer, and do not describe any mechanism
for recovery of that physical layer clock, in fact you WILL be forced
to have bit slips at the egress IWF.

So, simply saying that the SSM is correct by definition,
and relying on magic to restore the proper clock,
is not meaningful.

Sorry for my previous incorrect statements.

Y(J)S