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Re: Optical Connectors

My 2 cents:

I chair the T11.2 (Fibre Channel Physical layer) Optical Working Group and have
been through many, many connector wars. I STRONGLY believe that neither the IEEE
nor T11 should standardize connectors for their 10 Gbps projects. My main reason
is that it will definitely extend the standard schedule by a significant amount
(I'd say 25 to 33%). The second reason is that because of the multiple PMDs
likely to address multiple objectives for both standards, each standard would
need to support multiple connectors. This implies multiple connector wars within
each standards body. My suggestion is to leave connector decisions to the
industry associations (preferred) or the marketplace. 

Best Regards,

> 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 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
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