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RE: [EFM] TDM circuit emulation

I would welcome a presentation on this topic.

If there is serious interest in supporting this application, while I think 
support for it is clearly outside the scope of the project, one approach 
would not be to define a PHY to support it but to leave wavelengths 
available so we do not break the ability of other implementations to 
support it.

Bruce Tolley
Cisco Systems

At 10:03 PM 12/9/2001 +0000, Bob Barrett wrote:

>I am interested in TDM over EFM and over IP, however, so far EFM has ruled
>TDM as out of scope or implementation specific.
>It is one thing to run TDM in packets, it is actually easier to run TDM in
>side bands, but that would mean changing the PHY. I was going to do a
>presentation on this in Portland but I pulled it because there appeared to
>be zero chance of changing the PHY at that point. If the group adopts OAM
>other than in frames the PHY will need to be changed, and at that time
>Pandora's Box will be open, so to speak, and I will come back in with my
>presentations. May as well be hung for a sheep as a lamb. I.E. if we are
>changing the PHY for OAM we may as well change it to add side band TDM.
>In all packet networks circuit emulation as frames or IP is needed in the
>metro / back-haul. Side band TDM won't cut it.
>In traditional networks circuits can be done as they are today, or at worst
>they need to be carried in the last mile / first mile along side the packet
>traffic, to where the SONET / SDH metro handles them in the back-haul.
>I have technology for both that I would be willing to contribute to EFM if
>the group were to feel that that was a desirable enhancement to the EFM
>There is certainly new silicon for EPON, probably for outside plant 1GE, and
>probably for 10Base4 copper. However, I see the applicability being EPON and
>1GE only, unless there is a benefit in changing the T1/E1 from its current
>copper coding to something else to reduce cross-talk on the copper PHY.
>Hugh / Howard - any comment on this from the copper track please?
>Best regards
> > -----Original Message-----
> > From:
> > []On Behalf Of ???
> > Sent: 09 December 2001 15:39
> > To: stds-802-3-efm@xxxxxxxxxxxxxxxxxx
> > Subject: [EFM] TDM circuit emulation
> >
> >
> >
> > Hello,
> >
> > What do you think of T1/E1 and T3/E3 circuit emulation over EFM?
> > Some vendors have announced TDM integration over IP.
> > It might be some problematic in cost/performance due to cost of
> > delay/jitter compensation. And how about supporting resiliency?
> >
> > Jangrai Roh