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AW: [EFM] TDM circuit emulation

Kent and All,

All the more reason for defining
an enhancement band where TDM, or other services, can be transported.


-----Ursprüngliche Nachricht-----
Von: kmccammon@xxxxxxxxxxx [mailto:kmccammon@xxxxxxxxxxx]
Gesendet am: Mittwoch, 12. Dezember 2001 19:45
An: btolley@xxxxxxxxx; bob.barrett@xxxxxxxxxxxxxxxxxx;
Betreff: RE: [EFM] TDM circuit emulation

Bruce and all,
SBC does consider that next generation fiber access solutions should support
TDM such as T1 and voice services. If TDM services must be done on a
separate wavelength and not with the PHY below 802.3 MAC, the EFM optics
group should pick a wavelength plan that can support wavelength evolution. 

Kent G. McCammon
Access and Video Technologies
SBC Technology Resources, Inc
4698 Willow Road
Pleasanton, CA 94588
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> -----Original Message-----
> From: Bruce Tolley [mailto:btolley@xxxxxxxxx]
> Sent: Sunday, December 09, 2001 6:19 PM
> To: bob.barrett@xxxxxxxxxxxxxxxxxx; stds-802-3-efm@xxxxxxxxxxxxxxxxxx
> Subject: RE: [EFM] TDM circuit emulation
> Bob:
> 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:
> >Jangrai
> >
> >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
> >specification.
> >
> >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
> >
> >Bob
> >
> > > -----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