Re: [RPRWG] Phy Layer question
Hi Vasan
If SONET is the PHY between 2 RPR boxes, it will be a concatenated STS-n path
signal point to point, only using SONET framing (maybe some monitoring bytes).
Therefore it will not be a SONET ring, and SONET will not be aware that RPR is
on a ring topology. Assuming the RPR boxes are equipped with SONET interfaces,
SONET paths will be generated in the origin RPR box and will be terminated in
the next RPR box.
You can also run into the case where the RPR box is connected to another RPR box
through a SONET ring, i.e., the RPR box will be connected to a SONET NE x (part
of the SONET ring) through an STS-n signal, the signal will be added/multiplexed
into the ring, will be dropped at another SONET NE y (part of the SONET ring),
and again the STS-n signal will continue point-to-point to the RPR box. But this
SONET ring will be transparent to RPR (as far as the RPR box is concerned, it is
a point to point SONET link to the next RPR box). In this case, you may or
maynot run the RPR traffic as protected. My feeling is that you shouldn't, since
RPR will be providing the protection.
I think it is unlikely that it will use any APS function of SONET (this
functionality is expected to be provided by the RPR). So for the RPR operation,
if it is SONET or GbE, it will be the same since it will not rely on lower layer
(e.g., SONET, GbE) in order to provide the functionality to higher layers (e.g.,
IP).
Hope that helps,
Angela
> I am new to the group. I have been reading up the presentations. I have a
simple question.
> We are saying .17 will be layer 1 agnostic. However, (if sonet is the phy
used) sonet is aware of the
> ring structure - for APS, etc.
> Will the .17 specify how a sonet framer should be defeatured to work with a
RPR MAC?
>
> Thanks,
> Vasan Karighattam
> Architect
> Intel Corporation
> 9750 Goethe Road
> Sacramento, CA 95827
> (916)855-5177 x4907