Re: [8023-10GEPON] Downstream wavelength review
Dear Marek,
I would like to explain my thought again because I feel my thought is
not understood well.
(1)I have already accepted the proposal of Frank's additional compromise
(about addition to footnote).
Basically, I believe we do not have to limit the wavelength because we
can freely choose the center wavelength from the range of Option D.
http://www.ieee802.org/3/10GEPON_study/email/msg00655.html
However I can compromise Frank's thought that the nominal wavelengths
remain the 1580 to 1600 values if footnote can be added at least.
(2)I have already got Japanese vendor's opinions.
I am sure they will agree to Option D, basically. But about a half of
them seem to consider the wavelength limitation as being premature
because power budgets have not been decided yet.
So I am not sure they will agree to Motion although I am sure they will
vote Option D in straw poll because Straw Poll does not limit the
wavelength range of Option D.
Then I said that we should not limit the wavelength range of Option D
yet, because I would not like to wait the decision of the power budget
ad-hoc any more.
(At least, I thought we should adopt full wavelength range as a baseline
because we would have chances to change it after the decision of power
budgets.)
But I would like to say that again, I can compromise if footnote can be
added at least.
Best regards,
Ken-Ichi
At 2007/08/31 15:34 Hajduczenia, Marek wrote:
> Dear Suzuki-san,
> What You are generally saying is that in order to decide the downstream wavelemngth, we need to wait for the outcome of the power budget ad-hoc, which is nowhere close to any kind of compromise regarding the numbers for downstream. It is a vicious circle and I believe that narrowing down the options for the downstream channel would help them focus on what they can do with the power budget.
> If You believe that the proposal for extended band i.e. 1574 - 1600 nm for all power classes would be accepted by everyone (so far I heard opinions of 4 people out of the whole group - where is everyone else ??), we could potentially indciate in the footnotes in the tables that PR10/PR20 classes are to aligned with CWDM grid in the case of uncooled devices. How would that sound ? This way we would have the best out of both solutions I believe and still we could get away with that in technical terms. Such a statement could be read then as follows: if You need to use a cooled device, feel free to chose where You want to transmit. If You use an uncooled device, use CDWM grid.
> Let's see how it this one sticks :)
> Best wishes
>
> Marek Hajduczenia (141238)
> NOKIA SIEMENS Networks S.A., Portugal - R
> Rua Irmãos Siemens, 1
> Ed. 1, Piso 1
> Alfragide
> 2720-093 Amadora
> Portugal
> * Marek.Hajduczenia@siemens.com
> http://www.marekhajduczenia.info/index.php
> (+351.21.416.7472 4+351.21.424.2082
> "C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg." - Bjarne Stroustrup
>
> -----Original Message-----
> From: Ken-Ichi Suzuki [mailto:kenyichi@ansl.ntt.co.jp]
> Sent: sexta-feira, 31 de Agosto de 2007 3:28
> To: STDS-802-3-10GEPON@listserv.ieee.org
> Subject: Re: [8023-10GEPON] Downstream wavelength review
>
> Dear Frank,
>
> Thank you for your response and proposal.
> It is only my concern.
>
> I think it depends on the decision of the power budget plan because:
> -If we use a PIN-PD for a PX/20 ONU receiver, I think an OLT transmitter
> will need cooled system because of its high out-put power more than 5 dBm.
> -Moreover, if we use an APD for PX30 and a PIN-PD for PX10, each OLT has
> almost the same output power range.
> So I thought the full wavelength window for PX10/20 was a good
> compromise to eliminate the dependency on the power budget plan.
>
> But, I feel your additional compromise is good for me as well.
>
> Best regards,
> Ken-Ichi
>
> At 2007/08/31 0:16 Frank Effenberger wrote:
>> Dear Ken-Ichi,
>>
>> I have a question about your idea: Why would somebody want to make an OLT that supports PX10-20-30?
>>
>> The whole point of making a PX10 or PX20 is to make a cheaper OLT. If you make an OLT that supports PX30, you will have already spent the extra cost to make the high-power OLT... You don't gain anything to down grade it.
>>
>> If you are thinking about just being able to say, "My OLT complies with PX10/20/30 optical specs," well, I doubt you will ever be able to do that. We haven't finalized the entire power budget yet, but it seems that in most proposals the PX10/20 are considerably lower in power. Are you going to try to implement power control? That's more cost, to make an OLT that does less!
>> I don't think it is an attractive feature.
>>
>> Marek correctly pointed out that the use of a band from 1580 to 1600 is very attractive for the reason that it coincides with the CWDM band plan. I worry that if we define the PX10 and PX20 band to be the 'odd' 1574 to 1600nm, then it confuses the issue.
>>
>> Toward a compromise, would you accept a situation where we specify the PX10 and PX20 Tx bands to be 1580 to 1600nm, but we add a note like:
>>
>> Note: Deviations of the PX10 and PX20 Tx wavelength down to 1574nm are permissible.
>>
>>
>> You may think this sounds strange, but I really think it adds value, in that the nominal wavelengths remain the 'normal sounding' 1580 to 1600 values, yet it gives you the latitude that you want.
>>
>> How about that?
>>
>> Sincerely,
>> Frank E.
>>
>>
>>
>>
>> -----Original Message-----
>> From: Ken-Ichi Suzuki [mailto:kenyichi@ansl.ntt.co.jp]
>> Sent: Thursday, August 30, 2007 4:37 AM
>> To: STDS-802-3-10GEPON@listserv.ieee.org
>> Subject: Re: [8023-10GEPON] Downstream wavelength review
>>
>> Dear Marek and all,
>>
>> Thank you for your answer.
>> So I believe we should not limit the wavelength range of PX10/20
>> transmitters considering both the use of CWDM grid and compatibility
>> to PX30 cooled-lasers, if there are no reasons for that limitation.
>>
>> Best regards,
>> Ken-Ichi
>>
>> At 2007/08/30 17:23 Hajduczenia, Marek wrote:
>>> Dear Otaka-san,
>>> >From what I gather from the presentations provided so far, the OLT transmitters required for PR30 systems have different requirements than PR10/PR20 ones - for once, they require (most likely) cooling which is not required (at least that is what I gather) for PR10s and PR20s. I would like to learn the opinions of components vendors - they are more likely to be familiar with market availability of 1580 - 1600 nm devices meeting PR10/20 requirements.
>>> Please note also that the ONU receiver remains a universal device, with the sensitivity window spanning between 1574 and 1600 nm, thus covering both PR10/20 and PR30 devices on the other end of the link. The only differentation here would be the OLT transmitter, nothing else.
>>> Any other comments ?
>>> Thank You for Your feedback
>>>
>>> Marek Hajduczenia (141238)
>>> NOKIA SIEMENS Networks S.A., Portugal - R
>>> Rua Irmãos Siemens, 1
>>> Ed. 1, Piso 1
>>> Alfragide
>>> 2720-093 Amadora
>>> Portugal
>>> * Marek.Hajduczenia@siemens.com
>>> http://www.marekhajduczenia.info/index.php
>>> (+351.21.416.7472 4+351.21.424.2082
>>> "C makes it easy to shoot yourself in the foot; C++ makes it harder, but when you do, it blows away your whole leg." - Bjarne Stroustrup
>>>
>>> -----Original Message-----
>>> From: Akihiro Otaka [mailto:ootaka@ansl.ntt.co.jp]
>>> Sent: quinta-feira, 30 de Agosto de 2007 9:18
>>> To: Hajduczenia, Marek; STDS-802-3-10GEPON@listserv.ieee.org
>>> Subject: Re: [8023-10GEPON] Downstream wavelength review
>>>
>>> Dear Marek and all.
>>>
>>> Thank you for your prompt comment.
>>> This is Akihiro Otaka.
>>>
>>> I think if there are someone who try to realize B++ and PX20/10
>>> OLT with identical device (it may be a cooled device), the superset
>>> band idea is better for them.
>>>
>>> Are there no such requirement in practice?
>>>
>>> Best regards,
>>> Akihiro Otaka
>>>
>>>
>>> At 16:18 07/08/30, Hajduczenia, Marek wrote:
>>> >Dear Suzuki-san,
>>> >
>>> >I believe I may answer this question since Frank is probably still at night
>>> >time (Frank, please confirm if I what I am saying is OK) ...
>>> >The main reason why Frank proposes to have PR10/PR20 PMDs use the 1580 -
>>> >1600 nm window in the downstream is the compatibility with the CDWM
>>> >wavelength grid and the availability of uncooled transmitters centered
>>> >around 1590 nm with the power putput sufficient to cope with these
>>> >particular power budgets. You are right that it does little harm to expand
>>> >the band to 1574 - 1600 though the big question is whether it will be used
>>> >in practice. I do not see a reason to block part of the band which will not
>>> >be used by the PMDs anyway.
>>> >
>>> >Hope that answers Your question
>>> >
>>> >Marek Hajduczenia (141238)
>>> >NOKIA SIEMENS Networks S.A., Portugal - R
>>> >Rua Irmテ」os Siemens, 1
>>> >Ed. 1, Piso 1
>>> >Alfragide
>>> >2720-093 Amadora
>>> >Portugal
>>> >* Marek.Hajduczenia@siemens.com
>>> >http://www.marekhajduczenia.info/index.php
>>> >(+351.21.416.7472 4+351.21.424.2082
>>> >"C makes it easy to shoot yourself in the foot; C++ makes it harder, but
>>> >when you do, it blows away your whole leg." - Bjarne Stroustrup
>>> >
>>> >-----Original Message-----
>>> >From: Ken-Ichi Suzuki [mailto:kenyichi@ansl.ntt.co.jp]
>>> >Sent: quinta-feira, 30 de Agosto de 2007 8:00
>>> >To: STDS-802-3-10GEPON@listserv.ieee.org
>>> >Subject: Re: [8023-10GEPON] Downstream wavelength review
>>> >
>>> >Dear Frank
>>> >
>>> >Thank you for your proposal.
>>> >Basically, I agree to your proposal.
>>> >But I have a comment on Option D.
>>> >
>>> >I believe the full wavelength range of 1574 to 1600 nm can be used
>>> >for PX10 and PX20 in Option D.
>>> >If someone wants to use the range of 1574 to 1580 for PX10 and PX20
>>> >as well as the range of 1580 to 1600 nm, I think we should not limit
>>> >the wavelength range of Option D.
>>> >
>>> >So I would like to confirm whether we should limit the wavelength
>>> >range because I believe that the specifications should be accepted
>>> >by as many people as possible (although I do not have a strong
>>> >opinion to PX10 and PX20).
>>> >
>>> >Best regards,
>>> >Ken-Ichi
>>> >
>>> >At 2007/08/29 0:07 Frank Effenberger wrote:
>>> >> Dear All,
>>> >>
>>> >>
>>> >>
>>> >> I have put together some slides that review the downstream wavelength issue,
>>> >> and put forward a solution that I think may have some common support.
>>> >>
>>> >>
>>> >>
>>> >> Please give me your comments, and if you would like to support it, let me
>>> >> know that, also.
>>> >>
>>>
>>>
>>>
>>
>
>
--
Ken-Ichi Suzuki
NTT Access Network Service Systems Labs.
E-mail:kenyichi@ansl.ntt.co.jp
Tel:+81-43-211-3189/Fax:+81-43-211-8250