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Re: 10000SX-4WDM-1.25

Hi Jaime,

Thanks very much for the appreciation but it really is no problem for me
uploading the files to the web site for you or anybody else. It is just
unfortunate that we as yet do not have a more automatic way for people to upload
presentation when they are too large for the e-mail reflector to handle.

   David Law

>Hello 10 G'ers,
>The pdf file I was referring to is already at the web site:
>Many thanks of appreciation  to David Law's support.
>Jaime Kardontchik wrote:
>> I apologize if you will receive this email twice: I sent
>> it several hours ago and I did not receive it back from the
>> Reflector. May be it got lost because it had a pdf file
>> attached to it. I deleted this pdf from the present email.
>>         *********************
>> Hello 10 G'ers,
>> I have talked to a pair of companies, that are
>> on the optical side of the equation, regarding
>> my original PAM-5 4-WDM at 1.25 Gbaud proposal
>> that I presented in Kauai, Nov 99, and in Dallas,
>> Jan 2000 (see presentations in the web site).
>> They suggested that if I modify my original
>> proposal and use short wavelength VCSEL lasers
>> instead of 1300 nm lasers, this modified proposal
>> would become very attractive to them. They feel that
>> important key optical (mux/demux) and electrical
>> analog front end blocks are well within their
>> capabilities to manufacture them and that it
>> could meet the tight schedule of the Task Force
>> because it uses mainstream available technologies
>> and an already existing and standardized PCS
>> (except for linearity issues, specially of the
>> lasers, that will have to be addressed before
>> the July 2000 meeting).
>> Essentially, using short wavelength lasers this
>> proposal will have the following advantages:
>> 1) It will be the cheapest 10 GbE system that
>>    supports the installed multimode fiber.
>>    It will use cheap active optics at 1.25 Gbaud
>>    (VCSELs and Silicon photodiodes) and cheap
>>    optical mux/demuxes.
>> 2) It will support up to 160 meters of the
>>    installed MMF (160 MHz*km fiber), meeting
>>    easily the minimum HSSG objective (100 m).
>>    At 160 meters the optical eye is wide open:
>>    there is no need for equalizers.
>> 3) It will support much longer link lengths at a
>>    much lower cost that any serial 10 Gbaud
>>    approach using the installed MMF (the latter
>>    supports a bare 25 meter using 850 nm
>>    lasers and 85 meters using 1300 nm lasers;
>>    see Dallas spreadsheet).
>> 4) It uses 1.25 Gbaud on 4 Copper traces.
>>    It allows the use of standard layout
>>    practices and cheap FR4-based PCBs and
>>    backplanes
>> 5) It uses mainstream CMOS technology,
>>    reducing packaging costs and allowing
>>    larger integration (for example, on chip
>>    CMOS transimpedance amplifiers)
>> 6) It reuses the 1000BASE-T PCS, another
>>    Ethernet standard, saving considerable
>>    development time.
>> Notes:
>> a) this proposal will support officially
>>    only link lengths that assure a nice
>>    opening of the optical eye pattern at
>>    the receiver. Hence, there is no need
>>    for any equalizer. However, after the
>>    Standards are completed, individual
>>    companies could come to the market
>>    offering their proprietary solutions
>>    (that could include Decision Feedback
>>    Equalizers) to support link lengths
>>    well above 160 meters.
>> b) The decision of whether to use the
>>    6-dB coding gain option of the PCS
>>    (Viterbi decoding) or the 3-dB option
>>    (standard symbol-by-symbol decoding)
>>    will be reached by the July 2000
>>    meeting after consulting with the
>>    interested parties.
>> c) copy of this proposal was presented to
>>    Broadcom on Feb 2, urging it to consider
>>    it as a common PAM-5 proposal to be
>>    presented in the March 2000 meeting.
>> If the proponents of PAM-5 solutions cannot
>> agree to a common supported approach in the
>> March 2000 meeting, I consider the odds of
>> joining the standardization track very slim
>> if not zero, in light of the existent Task
>> Force schedule that includes an initial Draft
>> in July 2000 and a demonstration of working
>> prototypes by July 2001.
>> Jaime
>> Jaime E. Kardontchik
>> Micro Linear
>> San Jose, CA 95131
>> email: kardontchik.jaime@xxxxxxxxxxx