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Re: Optical Connectors


The discussion has gone far afield of the traditional bounds for standards 
based discussions.
I know that you feel duty bound to protect your product.
To that end, and to also support my purposes, can we please haul the 
discussion back to:
         * Specifications for any particular connector that are actually 
included in a standard adopted by by a national or international SDO.
         * Specifications (detail or overall) that have actually been put 
on the table and have not yet been rejected by a considering committee of 
an SDO.

If your attached message already meets these criteria then I apologize and 
would ask that you still point these things out in standards based terms.

Thank you.


At 10:57 AM 7/28/00 -0500, wrote:

>There is a very fine line between technical discussion and a marketing
>pitch. Following yours <Please let me know if anything is amiss. Let's try
>and maintain objectivity here> I feel obligated to reply to your note as it
>misleads those that are not experts in this field.
>First of all set of numbers associated with each connector you've presented
>is very misleading. As you know there is a big difference between the mean
>and the maximum insertion or reflection loss values or between multi mode
>and singlemode fiber. Please be specific next time around.
>Second, for your and other reflector subscribers information the VF-45
>singlemode insertion loss mean value as published more than a year ago in a
>technical report, available upon request, is 0.19 dB with back reflection of
>negative 56 dB.
>Third, the 4.9 fiber pitch of VF-45 reflects the active devices can size not
>the ability of the VF-45 ferrule-less connector technology or active devices
>to space the fibers and/or active devices at larger pitch or as close as 250
>micrometers apart.
>Forth, I don't know if you're referring to the cable or fiber so let me
>elaborate on both. The duplex cables are manufactured in both so-called
>zip-cord and round structures. While zip-cord is used typically for the
>jumpers due to ease of termination and ability to recover failed termination
>of the single ferrule connectors such ST, SC or LC the round is used in the
>typical cabling environment. The VF-45 represents an innovative,
>ferrule-less, plug and socket design in a RJ-45 format. The in-field
>installable socket can be terminated onto any cable design while jumper is
>provided as factory made product in a similar to UTP fashion.
>If you're making references to fiber I advise you to check L.K. Baker, G.S.
>Glaeseman, Corning's fiber reliability experts, paper titled "A mechanical
>reliability study of bare fibers under stress" presented September '99 at
>the IICIT conference. To make the long story short here are Corning's
>conclusions for VF-45 wall socket:
>" The results show that wall socket terminated with silica fiber have a very
>low failure probability of 0.04% over 20 years. This corresponds to a 2.5
>FIT (failures per billion hours), which means that over 20 years
>approximately one wall socket would fail for every 1,000 installed.
>and VF-45 plug:
>"The results show that for the jumpers manufactured with either standard
>silica glass or a high durability fiber with the proof test operation the
>predicted failure rate falls to zero over the 20 years service life"
>And one more thing in case you don't know. All this for one-seventh the cost
>of the traditional ferrule-like connector design.
>----- Original Message -----
>From: <mittalr@xxxxxxxxxx>
>To: Roy Bynum <rabynum@xxxxxxxxxxxxxx>
>Cc: <stds-802-3-hssg@xxxxxxxx>
>Sent: Thursday, July 27, 2000 7:17 PM
>Subject: RE: Optical Connectors
> >
> >
> > Roy, I do not believe your assesment is correct. I can give you name of at
> > least 6 other BIG companies who are doing LC. That is more than you can
> > count for MT-RJ, I'm sure.
> >
> > I think it will be instructive to give people a feel of the various pros
> > cons of various small form factor devices. Please let me know if anything
> > amiss. Lets try and mantain objectivity here.
> >
> > LC
> > ---
> > Fiber pitch: 6.25mm (simple and easy to manufacture)
> > Insertion loss 0.1-0.15dbm
> > Return loss: 50-60dbm
> >
> > Mu
> > ---
> > Very similar to LC
> > Only difference is lack of latch which might be
> > depending upon whom you talk to
> >
> > MT-RJ
> > -----
> > Fiber pitch: 0.75mm(difficult to manufacture)
> > Insertion loss 0.15-0.2 dbm
> > Return loss: ~40dbm
> >
> > VF (volition)
> > ----
> > Fiber pitch: 4.9mm(special cabling reqd.)
> > Insertion loss 0.5dbm
> > Return loss: ~20dbm
> >
> > Thanks
> > Rohit
> >
> > ps: I agree with a lot of people on this reflector that it doesn't make
> > sense to get into these discussions on and on. Everyone has their own
> > favourite connector and the protocol is anyway independent of whether you
> > use SC or LC or MT-RJ.
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > _______________________________________________________
> > Say Bye to Slow Internet!
> >
> >
> >