Re: [8023-10GEPON] Revised 10G budget
Dear Marek,
Thank you for your informative feedback, patience, and advice. I have a clearer understanding of how the committee has arrived at this point in the process of developing the standard. I will take your advice and do a review of the past research before attending upcoming meeting in Atlanta.
Best regards,
Ken Maricondo
-----Original Message-----
From: Hajduczenia, Marek [mailto:marek.hajduczenia@nsn.com]
Sent: Wednesday, October 17, 2007 11:48 PM
To: Ken Maricondo; STDS-802-3-10GEPON@LISTSERV.IEEE.ORG
Subject: RE: [8023-10GEPON] Revised 10G budget
Dear Ken,
Thanks for the feedback. It is nice to see someone actually follows this reflector thread.
As for Your questions, I will try to answer below:
Ad. 1) P2MP - that is logical for PON. The exact P2MP is not defined, since the transmission protocol is PON structure agnostic meaning that it will run well on tree-and-branch as well as on bus topologies. P2P is rather specific to standard Ethernet links. I believe the point of using PON is the limited fibre and transceiver deployment cost ...
Ad. 2) we do not define the maximum and minimum split ratio for the system. We define typical split ratios for which the power budgets were considered and analyzed (i.e. 1x16 and 1x32). The 802.3av standard will state in Clause 91 that "at least 1x16 and 1x32 split ratios" are supported. As for the min and max values. Once You have the power budget for the link, You are free to shorten the fibre and increase the split accordingly, or vice versa, as long as the total channel insertion loss still fits inside of the envelope defined in the standard. We will not define the splitter type. Feel free to use anything that guides optical signals. Obviously, the better the splitter, the lower the loss and the more of the power budget can be used for supporting customers, though that it is an obvious observation.
Ad. 3) I am not sure we ever consider that as a stand-alone parameter. It is throw in the box called "fibre attenuation and penalties" and considered as a group. We do not need to examine the power budget down to the last 0.1 dB.
Ad. 4) Again, irrelevant for this standard. We will not specify that one needs to use APC or any other connectors. Feel free to use what is available and suits best Your needs.
Ad. 5) No. We will not event state that an EML is needed to make the system work, though the PMD parameters will probably take into account the EML like parameters. I suspect the parameters which will be adopted eventually will be based on EA EML rather than MZ EML mainly due to the cost issue - EA is still cheaper (correct me if I am wrong).
Ad. 6) SOA has not been chosen in any way and You will not see any reference in the standard to it. What was discussed was the fact that some sort of post amplifier may be needed for the OLT Tx side, though it has not been decided as for now whether it will be used and even when we do, we will specify the output power rather than saying "use SOA". Feel free to use SOA or EDFA, or any configuration of optical amplifiers You want and have at Your disposal, as long as You meet the output power specs.
Ad. 7) SBS control will not be defined in the PMD since it is out of scope of the IEEE 802.3av. I believe the consensus in the TF is right now that we do not have problems with the SBS as long as we keep the digital signal power under control and do not allow to exceed certain power levels, which were discussed in one of the ad hocs I happened to lead. Anyway, do not expect to see the specs for dithering in the standard - we will not define what dithering is (several ways to do it are available) and will not specify what are the dithering parameters. Since video overlay is an optional service, it is the carrier that must provide its operability, not IEEE in the EPON layer.
If I could make here a small comment - IMHO if You take some time and try to look through materials and baseline proposals we adopted so far, You will have a more detailed overview of the current status of this standard. Most of the questions You asked have direct answers in the 802.3ah and the current proceedings, which are public ally open. Additionally, please note that while "I suspect that most of the PMD parameters are probably extrapolated from previous standards" will probably hold true for a few parameters (perhaps Ton, Toff etc), the vast majority of the parameters which will be adopted eventually will be based on the test data, test bed implementations, trials etc. Additionally, we have 10GE technology to build on, so I think we are quite well off.
Hope that answers most of Your questions
Marek Hajduczenia (141238)
NOKIA SIEMENS Networks S.A., Portugal - R
Rua Irmãos Siemens, 1
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* 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 Maricondo [mailto:Ken.Maricondo@BIGBANDNET.COM]
Sent: quarta-feira, 17 de Outubro de 2007 22:37
To: STDS-802-3-10GEPON@LISTSERV.IEEE.ORG
Subject: Re: [8023-10GEPON] Revised 10G budget
Dear All,
I suspect that most of the PMD parameters are probably extrapolated from previous standards (802.3ah) and taken from numerous test data; but I am wondering how some of the non-PMD values influenced the PMD values so far, for example:
1. What architectures are being considered? P2P, P2MP, etc.
2. Maximum and minimum optical splits? What types, PLC, Fused, etc?
3. What is the maximum polarization dispersion for the given architectures?
4. What optical connectors are be used in the design? I suspect APC would be best for minimizing back reflections, etc.
5. Is there a preference on the type of external modulation? Electro-absorptive or Mach-Zender?
6. Is there a reason why SOA has been chosen? Would an EDFA be another allowable option?
7. Will SBS control be used in the OLT and will it be defined in the PMD?
If any or all of the above issues have already been addressed; please except my apologies in advance.
Thank you,
Ken Maricondo
-----Original Message-----
From: Glen Kramer [mailto:glen.kramer@TEKNOVUS.COM]
Sent: Thursday, October 11, 2007 3:53 PM
To: STDS-802-3-10GEPON@LISTSERV.IEEE.ORG
Subject: Re: [8023-10GEPON] Revised 10G budget
Dear Colleagues,
I am surprised by the lack of discussion following Dr. Effenberger's last posting of an updated PMD proposal. I hope the right explanation for this is that the task force is in agreement regarding the proposed PMD parameters and no one has any concerns, questions, or alternative proposals.
If my explanation is correct, please add your name as a supporter of this presentation. However, if you have any concerns or questions, please do not be silent and discuss this on the reflector now.
If you do disagree with any of the proposed parameters, please validate your concerns and/or post an alternative proposal.
I sincerely hope that we will not have a repeat of the situation where some people refrain from raising any concerns between the meetings, but argue against accepting any proposal at the meeting on the basis that more studies were needed. Now is the time to ask questions and do additional studies.
Our hottest item for November meeting is reaching consensus on enough PMD parameters such that we can produce draft 1.0 and initiate task force review phase.
Thank you,
Glen Kramer
Chair, IEEE P802.3av Task Force
________________________________________
From: Frank Effenberger [mailto:feffenberger@HUAWEI.COM]
Sent: Monday, October 08, 2007 1:48 PM
To: STDS-802-3-10GEPON@LISTSERV.IEEE.ORG
Subject: [8023-10GEPON] Revised 10G budget
Dear All,
I have taken some of the comments I received on my last Email, and modified the slides to come to the attached version.
What I’ve done is:
1. Reduce the PR10 OLT downstream transmitter Max and Min by 1 dB. (This reverts to the values presented in Takizawa’s slides in September)
2. Reduce the PR10 ONU Rx overload number by 1 dB. (Following the Tx change)
3. Increate the PR20 OLT max power by 1 dB (Makes the Tx range 4 dB, which is more comfortable)
4. Increase the PR20 ONU Rx overload number by 1 dB. (Following the Tx change)
Taken together, these changes then make the PR10 and PR20 ONUs identical in every respect. One less PMD!
This is re-capped on the last slide.
Sincerely,
Dr. Frank J. Effenberger 弗兰克 埃芬博格
Huawei Technologies USA
1700 Alma Drive, Plano TX 75075
Office (732) 625 3002
Cell (908) 670 3889