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Re: [802.3_NGEPON] Call for agenda items -- weekly consensus building for IEEE 802.3ca (100G-EPON)

Vincent,

Yes, the EA modulator dc bias and driver swing are different for NRZ and PAM4.  ER(outer) for PAM4 is limited by linearity to ~5dB.  It's possible to switch dc bias and driver swing dynamically to get higher ER NRZ, but there would need to be some settling time between frame which might make ONU CDR even more difficult since it becomes more like burst mode.

Regards,
John

On Thu, Oct 26, 2017 at 1:02 PM, Houtsma, Vincent (Nokia - US/Murray Hill) <vincent.houtsma@xxxxxxxxxxxxxxxxxxx> wrote:

John,

 

Regarding your last comment, not being able to switch ER between NRZ and PAM4 is this related to the linearity you will need for PAM4 compared to NRZ ? I guess you can reduce driving voltage for PAM4 to make it more linear (and thus reduce ER as well). You will still need linear drivers at the transmitter though which might increase your 25G NRZ penalty as well.

 

I am also concerned about 25G NRZ CDR keeping its lock during PAM4 transmission due to the added power penalty, since it will need to stay locked to middle eye of the PAM4 signal during 50G transmission.

 

Regards,

Vincent

From: John Johnson [mailto:000007ff7d378f43-dmarc-request@xxxxxxxx]
Sent: Thursday, October 26, 2017 09:30
To: STDS-802-3-NGEPON@LISTSERV.IEEE.ORG
Subject: Re: [802.3_NGEPON] Call for agenda items -- weekly consensus building for IEEE 802.3ca (100G-EPON)

 

These presentations and previous discussions bring up the question of whether there will ever be any market for 50G-EPON OLTs, and if there is, whether it would need to coexist with legacy PONs.  China Telecom wants to jump to 100G OLTs on top of XG(S)-PON networks, so 100G-EPON needs to coexist with 10G PON.  Upgrade of GPON directly to 25G-EPON with WDM coexistence is a reasonable scenario, but it then seems likely that the next step in the far distant future would be 100G-EPON, presumably without a need for further GPON coexistence.  

 

So 100G-EPON needs WDM CE with 10G-EPON, 25G-EPON needs WDM CE with GPON, and it's not clear what CE is needed for 50G-EPON, or if there is any market for 50G-EPON at all.  If we can agree that 50G-EPON is likely not going to be deployed in any significant volume, then we might also agree that the CE requirements may be relaxed for 50G-EPON.  Comments?

 

Question for Dekun:  What is the view of China Telecom regarding TDMA of 25G and 50G on the same wavelength for US and DS?  Is this an acceptable solution from a capacity standpoint?  

 

One comment for dual bit rate downstream is that it is difficult to change OMA and ER on the fly without adding extra settling time between frames, so the NRZ signal may have to be limited to the lower ER that is used for PAM4 (~5dB).  

 

Regards,

John

 

On Thu, Oct 26, 2017 at 5:53 AM, Liudekun <liudekun@xxxxxxxxxx> wrote:

Curtis, all,

 

I will bring in a contribution on 25G/50G dual rate channels if the time slot is still possible

 

( I hope I don’t have a problem to access the telephone meeting from the network in the other side of the pacific ocean)  

 

Best regards

Dekun Liu

____________________________________________________

Advanced Access Technologies Dept. 网络研究接入技术部

Huawei Technologies Co., Ltd. 华为技术有限公司Company_logo
  Phone: +86 027-59267217  Email: liudekun@xxxxxxxxxx

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Huawei Technologies Co., Ltd.

A7-9 Wuhan Optical Valley Software Park,Guan Shan Road,Wuhan,Hubei, P.R.China

 

 

From: Curtis Knittle [mailto:C.Knittle@CABLELABS.COM]
Sent: Monday, October 23, 2017 11:13 PM
To: STDS-802-3-NGEPON@LISTSERV.IEEE.ORG
Subject: [802.3_NGEPON] Call for agenda items -- weekly consensus building for IEEE 802.3ca (100G-EPON)

 

Dear Colleagues,

 

We have the 100G-EPON (IEEE 802.3ca) consensus building meeting scheduled for this Thursday, October 26, 11:30 am – 1:00 pm MDT. Please let me know by 5:00 pm MDT Wednesday if you have any topics for the agenda.

 

As a reminder from the closing report of our last F2F meeting in Charlotte, the following topics were deemed important for contributions:

 

  • Actions:
    • Power budget
      • Close on 25Gbps power budget (Ed/Dekun/Umeda)
      • Characterization method for both transmitter and receiver (Dekun, John J, Vincent, Junwen, Frank, Greg, Umeda-san)
    • MPCP/MPRS
      • Discovery process / configuration / ONU capabilities field in RegREQ (Glen Oct 12 – Glen to doodle poll)
    • Fault Tolerance/Recovery/Loss of Channel
    • Wavelength plan
      • Peacemaker plan (Glen/Frank/Ed/Yong)
    • SOA preamp/dynamic range
      • Cost and feasibility still needs to be demonstrated (Dekun)
    • Line coding (Postponed until after FEC decision)
    • FEC information
      • Comparisons of parity matrices and different FEC (Mark/Bill/Bo)
      • Loud/soft ONU analysis – (Bill)
      • Operating in burst mode at 1E-2 (Vincent)
      • Latency (Shan)
      • Define a common set of assumptions and parameters common to all FEC analyses
        • Mark to send email after noodling
    • SERDES/CDR
      • Check margin for 10^-2 input BER (Yin, Ryan)
    • 50G single wavelength
      • Technical feasibility of upstream bursts (Critical path item)
      • Wavelength plan
      • Power budget
      • Modulation

 

 

Thank you,

 

Curtis

 

 

 

 

Curtis Knittle

VP Wired Technologies – R&D

CableLabs

desk: +1-303-661-3851

mobile: +1-303-589-6869

c.knittle@xxxxxxxxxxxxx

 

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