RE: [EFM] Network timing? [Etherloop?]
All,
I haven't read the 1GE spec. (shame on me) but I think the clock requirement
is pretty tolerant compared to SONET/SDH where the bearer timing is critical
and synchronised.
Therefore 1GE bearer can't be relied upon for timing in the circuit (frame
sync or Stratum) sense.
Therefore timing in the circuit sense would have to be carried in the
payload plesiochronosly. I hope that I have that word spelt correctly, and
the grammar of this comment correct (Emil :-) ).
Therefore any discussion of how it's done is not within the scope of EFM.
End of thread ?
Bob Barrett
> -----Original Message-----
> From: owner-stds-802-3-efm@majordomo.ieee.org
> [mailto:owner-stds-802-3-efm@majordomo.ieee.org]On Behalf Of Vladimir
> Oksman
> Sent: 28 September 2001 14:29
> To: fkittred@gwi.net
> Cc: Beanland Matthew; stds-802-3-efm@ieee.org
> Subject: Re: [EFM] Network timing? [Etherloop?]
>
>
>
> Fletcher,
>
> if timing reference is not transported over the last mile,
> it will never
> reach the customer. I think it doesn't make a lot of sense to
> provide timing
> reference over fiber and just terminate it at the ONU or local
> exchange. Seems,
> copper should be involved as well.
>
> Vladimir.
>
>
>
> Fletcher E Kittredge wrote:
>
> > On 27 Sep 2001 10:21:00 +1000 "Beanland Matthew" wrote:
> > > I was thinking principally fiber, although I am aware of VDSL
> systems which
> > > perform E1/TI transport. By the reference to the PABX I'm
> thinking business
> > > rather than residential.
> >
> > If you are talking fiber only; then I have no objection. Adding this
> > to the copper standard is problematic.
> >
> > thanks,
> > fletcher
>
>