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RE: Optical Connectors




Chris, Jonathan, et al.

I think this issue would be best explored by an ad hoc commissioned by 
Jonathan or Walt. The ad hoc could then come to the task force with some 
recommendations based on data. Claims are being made for the market success 
of MT-RJ and LC that might be true in specific instances or in specific 
sites but not true for the market as a whole. Some real data would be 
helpful to aid the process of deciding.

Bruce

At 08:47 PM 7/23/00 -0500, Roy Bynum wrote:

>Chris,
>
>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
>>Picolight
>>
>>-----Original Message-----
>>From: Roy Bynum [mailto:rabynum@mindspring.com]
>>Sent: Tuesday, July 18, 2000 12:09 PM
>>To: Jonathan Thatcher; HSSG_reflector (E-mail)
>>Subject: Re: Optical Connectors
>>
>>
>>
>>Jonathan,
>>
>>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
>> >9.9.5.2 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
>>transceiver.
>> >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@worldwidepackets.com
>> >
>