Re: PMD discussion
[Date: 05/29/2000 From Seto]
Hello Ed,
The answer is no. I'm suggesting another set of '3' PMDs.
Seto
> Seto:
>
> A question for you.
>
> If you read Walter's statement carefully, then sent out your comment. I
> believe your are proposing 4 PMDs. Correct?
>
>
> Regards,
>
> Edward S. Chang
> NetWorth Technologies, Inc.
> EChang@xxxxxxxxxxxxxxxx
> Tel: (610)292-2870
> Fax: (610)292-2872
>
>
>
> -----Original Message-----
> From: owner-stds-802-3-hssg@xxxxxxxx
> [mailto:owner-stds-802-3-hssg@xxxxxxxx]On Behalf Of Seto, Koichiro
> Sent: Monday, May 29, 2000 10:25 AM
> To: wthirion@xxxxxxxxxxxx; stds-802-3-hssg@xxxxxxxx
> Subject: Re: PMD discussion
>
>
>
> [Date: 05/29/2000 From Seto]
>
> Walter,
>
> My understanding is that the following set is also one of the top
favorites:
>
> ________________optimized for may be used for
> 1310 nm WWDM MMF upto 300m SMF upto 10km
> 1310 nm Serial SMF upto 10km MMF upto 86m
> 1550 nm Serial SMF upto 40km
> ________________
>
>
> I understand there are some risks that 850nm-WWDM solution may not
satisfy
> laser eye safety as Jonathan pointed out in the discussion on Thursday.
> Also, I learned that there are some risks that 1310nm-WWDM may not be
able
> to achieve 10km at SMF if not impossible. At least we have not seen any
> data that would prove the feasibility of 1310nm-WWDM over 10km SMF. It
is
> not to say that this can not be done, but I have not been convinced that
the
> same 1310nm-WWDM optics at same cost factor will serve for both 300m
MMF
> and 10km SMF. Also, some people pointed out that 1310nm-Serial can be
built
> at cost factors of x1.8 to 850nm-Serial while 1310nm-WWDM is x3. If we
can
> achieve the same goal (SMF 10km), the cheaper is the better.
>
> I hope no one is offended by my not-so-educated opinion. I would
appreciate
> a healthy discussion.
>
> Seto
>
> >
> > First of all, thanks to everybody that presented PMD proposals at the
last
> > meeting. I've sent my presentation to David Law, so it should be
available
> > on the web site in the next couple of days.
> >
> > In listening to the discussion after my presentation and then going
around
> > and talking to people, it feels to me like we're starting to converge.
Not
> > there, yet, but making progress.
> >
> > The equipment manufacturers made it pretty clear they would like to
see no
> > more than 3 PMDs in the standard. The PMD vendors have some concern
that
> > using only 3 PMDs may sub-optimize certain objectives, however, they
could
> > support the 3 PMD position if it is made clear which 3 PMDs the
equipment
> > oems want.
> >
> > Based on an informal straw poll and anecdotal evidence, my opinion is
the
> > first choice would be the set:
> > ________________
> > 850 nm WWDM
> > 1310 nm WWDM
> > 1550 nm Serial
> > ________________
> >
> > If that set isn't feasible, then the 2nd most popular choice is:
> > ________________
> > 850 nm WWDM
> > 1310 nm Serial
> > 1550 nm Serial
> > ________________
> >
> > Thoughts, feedback?
> >
> > Walt
> > ___________________
> > Walter Thirion
> > Chair, IEEE 802.3ae PMD Sub-Task Force
> > 301 Congress Ave.
> > Suite 2050
> > Austin, Texas 78701
> > Voice: 512-236-6951
> > Fax: 512-236-6959
> > wthirion@xxxxxxxxxxxx
> > ___________________
> >
> >
> >
>