Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

RE: Optical Connectors


First of all, I'm not trying to sell Lucent.  We (Picolight) are an optical
transceiver manufacturer.  We are an unbiased implementer of receptacles
that go on our modules.  We look at all the options, choose what we think
are the best connector solutions and use them.

Below, I'm talking about a connector comparison, not an application.  The
only application issue that applies here is the fact that it's singlemode.
At the connector level, it doesn't matter between say Lucent's application
vs a start-up's application.  Insertion loss, mechanical alignment,
durability, gorilla testing, thermals, etc... are the items that matter
here.  I guess I don't understand why Lucent's field experience does not
apply here.  Actually, you'll find that field experience is THE most
important criteria in the standards process.

Regarding other OEM's use of the LC.  I would disagree.  There are quite a
few OEM's that are testing (or have tested) products with LC connectors.  To
say that only Lucent and a few startups are using LC is not true.

Please don't lead this thread to an application issue.  It's a connector
issue....and we think the connector of choice is the LC. Whether it's from
Lucent or Radio Shack.


-----Original Message-----
From: Roy Bynum [mailto:rabynum@xxxxxxxxxxxxxx]
Sent: Thursday, July 27, 2000 3:19 PM
To: Chris Simoneaux; HSSG_reflector (E-mail)
Subject: RE: Optical Connectors


Lucent marketing is probably correct in saying that they have been shipping 
LC connectors for years and that there are several K in the field.  You 
have to remember who Lucent was formerly a part of, AT&T.  AT&T has been 
and continues to be the primary customer for Lucent equipment including the 
LC connectors.  Lucent is attempting to expand their customer 
base.  However, every time that we look at something from Lucent, their 
primary customer's requirements are reflected more than anything else.

Lucent is only one vendor among many.  No other vendors, except for a few 
startups, have been bringing equipment into the lab that have LC 
connectors.  Even most of the startups are not using LC connectors.  AT&T 
is a BIG customer, but it is only one customer.  You need to take the 
Lucent marketing comments in context with where their market has been and 
continues to be.  Just because AT&T uses LC connectors on Lucent equipment 
does not mean that everyone else does, or should.

Thank you,
Roy Bynum

At 09:14 AM 7/27/00 -0600, Chris Simoneaux wrote:

>I would request Lucent to chime in here...but my understanding from their
>marketing guys is that they've been shipping LC connector systems for
>and 100's of K's of LC connectors are deployed in the field.  Most (or all)
>being in singlemode applications.
>-----Original Message-----
>From: Roy Bynum [mailto:rabynum@xxxxxxxxxxxxxx]
>Sent: Sunday, July 23, 2000 7:48 PM
>To: Chris Simoneaux; HSSG_reflector (E-mail)
>Subject: 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
> >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
> >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
> >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
> > >comments:
> > >
> > >-----------------------
> > >"Bill Wiedemann: Regarding 850CWDM we are planning to make first
> > >implementations with duplex SC moving to LC with small form factors.
> > >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,
> > >NOT specify conectors. "
> > >-----------------------
> > >"Ed Chang: There are so many different form factors, and connectors,
> > >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
> > >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
> > >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
> > >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
> > >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
> > >