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Re: Optical Connectors

A standard whose purpose is to guarantee the interoperability
of equipment is broken if two pieces of equipment built to that
stardard cannot be interconnected with a "standard cable".


> From: Jonathan Thatcher <Jonathan.Thatcher@xxxxxxxxxxxxxxxxxxxx>
> To: "HSSG_reflector (E-mail)" <stds-802-3-hssg@xxxxxxxx>
> Subject: Optical Connectors
> Date: Tue, 18 Jul 2000 08:48:32 -0700
> 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