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RE: Optical Connectors


I am not sure of your comment about LC having a proven track record for 
single mode implementations.  At present, WorldCom has not deployed any 
LC.  All of the connectors currently specified for SM installations is 
SC.  A particular vendor is attempting to get WorldCom to make use of their 
connectors.  ( I will not say how successful or not they are. )  Several 
system vendors are attempting to make use of LC, but at present, none have 
been certified.  Given the form factor that would use XAUI, SFF connectors 
would not be a requirement.

Thank you,
Roy Bynum

At 04:28 PM 7/21/00 -0600, Chris Simoneaux wrote:

>Our opinion is that LC is a better connector than MTRJ.  The LC does not
>seem to suffer the possible damage that MTRJ can see with high mate/demate
>cycles...due to the guide pin action.  Also, the LC has a proven track
>record for singlemode whereas the MTRJ does not.
>PS: My feeling is the standards body's charter should be to specify a
>connector. However, there's too much rhetoric in the procedure. Therefore
>it's difficult to choose the best solution.  Inevitably the real winner/s
>will come forward. Conclusion: Choose a connector at the standards level as
>it can expose good points of each solution.
>Chris Simoneaux
>-----Original Message-----
>From: Roy Bynum [mailto:rabynum@xxxxxxxxxxxxxx]
>Sent: Tuesday, July 18, 2000 12:09 PM
>To: Jonathan Thatcher; HSSG_reflector (E-mail)
>Subject: Re: Optical Connectors
>In spite of what Lucent wants, the LC connector does not have the market
>support that MTRJ does.  MTRJ also has a smaller form factor than does
>LC.  I don't like and am specifying the non-use of LC on transmission gear
>because of the fragile "lock" tab that is on the connector.
>Thank you,
>Roy Bynum
>At 08:48 AM 7/18/00 -0700, Jonathan Thatcher wrote:
> >I have opened this thread to continue the discussion on optical
> >connectors. So far (what has come into my reader), we have the following
> >comments:
> >
> >-----------------------
> >"Bill Wiedemann: Regarding 850CWDM we are planning to make first
> >implementations with duplex SC moving to LC with small form factors. Our
> >expectation is that small form factor with LC could be available a year
> >from today. "
> >-----------------------
> >"Jim Tatum: I would assume that 802.3ae would do the same as 802.3z, and
> >NOT specify conectors. "
> >-----------------------
> >"Ed Chang: There are so many different form factors, and connectors, which
> >even the GbE and Fibre Channel market can not get consensus."
> >-----------------------
> >
> >If we review the 802.3 Ethernet specification, we see that we have
> >identified connectors for each variant (I don't remember an exception).
> >For example:
> >7.6.2 AUI Configuration cable
> > Optical for repeaters
> >...
> >38.11.3 MDI = Duplex SC for GigE Optics
> >39.5.1 MDI = Style 1 (DB9) and Style 2 for GigE Cu
> >
> >While I remember no rules that require us to do so, it seems obvious that
> >there exists a precedent which should guide our decision.
> >
> >In 802.3z, we specifically took a vote to avoid connector discussions
> >("connector wars")**. We could do the same in 802.3ae. If we did, I would
> >argue that we would, effectively, be retaining the duplex SC optical
> >connector specified in clause 38.
> >
> >My PERSONAL preference would be to specify the LC connector. Rationale:
> >1. There seems to be an overall inclination to move in that direction.
> >2. It sets the stage for some kind of "Small Form Factor" 10 Gig
> >3. I don't think that it would negatively impact the cost of the
> >transceiver in the 2002 (standard completion time frame).
> >
> >As CHAIR, I don't want to use up any cycles on this. If there isn't
> >sufficient consensus to agree on an alternative to the SC, we should just
> >adopt the SC and move on.
> >
> >jonathan
> >
> >** In reality, this was bumped up to 802.3 because neither I (sub-chair
> >for PMD) nor Howard (802.3z chair) wanted to use precious committee time
> >for the discussion.
> >
> >Jonathan Thatcher,
> >Chair, IEEE 802.3ae (10 Gigabit Ethernet)
> >Principal Engineer, World Wide Packets
> >PO BOX 141719, Suite B; 12720 E. Nora, Spokane, WA 99214
> >509-242-9000 X228; Fax 509-242-9001; jonathan@xxxxxxxxxxxxxxxxxxxx
> >