RE: Multi-mode PMDs
The application of 1310 VCSEL is primarily in the multimode utilization of
1310 WWDM to achieve 300 meter. It is not enough for serial application to
achieve 100 meter --- using BW of 500 MHz-km.
The main question is the 1310 VCSEL volume production schedule and price,
which the 850 VCSEL has well established for a long time without any doubt.
For 1310 VCSEL, it is an expectation, which needs time to prove.
Edward S. Chang
NetWorth Technologies, Inc.
From: Mike Bennett [mailto:MJBennett@xxxxxxx]
Sent: Tuesday, August 29, 2000 7:26 PM
To: Edward Chang
Cc: Roy Bynum; hssg
Subject: Re: Multi-mode PMDs
Ed, Roy, et. al,
I sent mail to the reflector (subject 1300 nm VCSELs, date:Wed, 16 Aug 2000)
order to get the discussion going on short reach PMDs. I hope folks are
busy and just haven't had the time to discuss the issue here on the
I'd like to hear your opinions regarding the 1300 nm VCSEL and its potential
impact on the low cost short reach application space. I'm of the mind that
fewer PMDs is better, but I was not willing to vote in favor of fewer PMDs
without being assured of a low cost option for the short reach application
space. If 1300 nm VCSELs are going to be available in a reasonable time
than 1 year), and the mode conditioner is not needed for <= 100m then it
much more difficult to argue in favor of more PMDs. I'd much rather see the
discussion start now, rather than burn time at the interim with the same old
arguments ending in up with no concensus.
Edward Chang wrote:
> Roy and All:
> It seems that we did not get the consensus of which specific PMDs we need
> addition to 1550 and 1310 serial. However, it seems we have the
> or the majority of desire, to have short reach, cost-effective PMDs, which
> will include the VCSEL based approaches.
> Since many factors we have been debating to further narrow down the
> selection lists are based on the future market trends and many technical
> assumptions, we have had quite verities of different opinions; as a
> we were unable to obtain a consensus. I do not think the situation will
> better, unless we take a lot of time in debating and testing by prolonging
> the schedule, which is unlikely the path we can afford to take.
> I think we should let all PMDs on the table to be adopted, and let us move
> on to the next target, instead of trying to pin down factors which are not
> under our control.
> Edward S. Chang
> NetWorth Technologies, Inc.
> Tel: (610)292-2870
> Fax: (610)292-2872
> Subject: Multi-mode PMDs
> Where are we in the discussion of the multi-mode PMDs? There has not been
> much on the reflector of late. The last that I have on this does not
> indicate to me that there has been any consensus established. The last
> that I have, indicates that the system vendors and other members of the
> 10GEA are still wanting the 1310nm solutions, and the rest of the TF are
> wanting the 850nm solutions.
> Has this subject been moved to an Ad Hoc? Has this discussion been moved
> to a different forum/TF?
> Thank you,
> Roy Bynum