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Re: Optical Connectors




Rohit,

...and I'll add to the end of your statement:

...as it has for Gigabit Ethernet, Fibre Channel and other key standard
as well as proprietary transports.

Best Regards,
Rich
       
--

Rohit Sharma wrote:
> 
> For a telecom service provider, the use of LC connectors recommended for
> 10GbE transceivers will not affect whether they recommend SC connectors for
> their networks since the service providers typically connect to the
> equipment via Fiber trays which adapt whichever connector (SC, ST, APC,...)
> may be present on the equipment faceplate.  This year, several equipment
> vendors have shown deployed equipment with MU, LC, and other -- even
> proprietary connector types on certain ultra-long haul equipment in multiple
> networks in Metro, Long haul, submarine applications.  Most service
> providers continue to specify SC for connection to their fiber plant which
> is accomplished via fiber trays.
> 
> I do not believe that adoption of LC connector by IEEE precludes the
> (continued) use of SC connector by any network/service provider and moves us
> in the right direction for SFFs @ 10G.
> 
> -rohit
> Rohit Sharma
> 
> >
> > 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@xxxxxxxxxxxxxx]
> > >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@xxxxxxxxxxxxxxxxxxxx

-- 

Best Regards,
Rich
                                      
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