Re: [HSSG] <HSSG-FO> Fiber Optic Ad Hoc Teleconference 12/18/2006
Rami
I do want to 2nd your proposal to add External Cavity DML to the list of
potential solutions. As you stated ECL can operate at
10Gb/s over 120 Km now. With adiabatic chirp negligible and dynamic
chirp low enough to operate over 120 Km at 10Gb/s
this makes them excellent candidate for the 5x20 or 4x25 Gb/s per lane.
Thanks,
Ali
Rami Kanama wrote:
>
> Ali,
>
> Since last year’s OFC, there have been other successful EDC
> demonstrations extending the reach of an 80km 10Gbps 1550nm ECL to 120km.
>
> Standard DFB DML are dominated by transient or dynamic chirp as well
> as adiabatic chirp, however in external cavity (ECL) DML, the
> adiabatic chirp is negligible and the transient chirp has both
> negative and positive components which can be optimized to extend the
> reach over fiber. In addition to that, due to the round trip of
> external cavity resonance, the modulation bandwidth can be up to 20GHz
> or more.
>
> For this reason, 1550nm cooled external cavity based DML should be
> added to the list of potential solutions for 20-25Gb/s per lane.
>
> Regards,
>
> Rami Kanama
>
> Redfern Integrated Optics (RIO), Inc.
>
> Mobile: (408) 386-3191
>
> -----Original Message-----
> *From:* Ali Ghiasi [mailto:aghiasi@BROADCOM.COM]
> *Sent:* Monday, January 15, 2007 10:50 AM
> *To:* STDS-802-3-HSSG@listserv.ieee.org
> *Subject:* Re: [HSSG] <HSSG-FO> Fiber Optic Ad Hoc Teleconference
> 12/18/2006
>
> Frank
>
> For the last year OFC we had a demo using and external cavity DML
> operating over 80 Km in a SFP+ like form factor,
> the device had very little adiabatic chirp and the chirp was dominated
> by dynamic chirp. Our finding was that EDC had
> very little benefit in this case outside compensating for the FR4 trace.
>
> Standard DML are dominated by dynamic chirp which EDC will not be op
> much help.
>
> Thanks,
> Ali
>
> Frank Chang wrote:
>
> One datapoint is current EDC seems working very well for the type of
> positive chirp coming from short-reach EMLs. I agree its interesting
> to investigate the impact of DML type of positive chirp.
>
> Obviously the tweaking of EDC circuit should be done with the change
> in its link/media characteristics. Also EDC could be implemented in
> several ways such as at the Rx, pre-distortion at the TX or E-field
> domain. So it should expect to play roles for 20/25G etc resulting
> from its ease of use and attractive economics.
>
> -Frank
>
> -----Original Message-----
> *From:* Mike Dudek [mailto:mike.dudek@picolight.com]
> *Sent:* Thursday, December 28, 2006 9:54 AM
> *To:* STDS-802-3-HSSG@listserv.ieee.org
> <mailto:STDS-802-3-HSSG@listserv.ieee.org>
> *Subject:* Re: [HSSG] <HSSG-FO> Fiber Optic Ad Hoc Teleconference
> 12/18/2006
>
> All,
>
> The EDC assumptions used for LRM (10G) development was that the
> dispersion effect is linear. (ie every one or zero is identical and
> the eye closure is created because the bit energy is not confined
> within one bit period and smears out over multiple pulses such that
> with superposition of the bits the eye closes. ie it's linear ISI that
> is being compensated.). It also assumes that the ones and zeros are
> inverts of each other. I think the problem for 1550nm DML is likely to
> be chirp. Does anyone know if chirp has this deterministic linear
> characterisitic and whether the ones and zeros are inverts of each
> other. (I don't think they are).
>
> I'm not suggesting that EDC can't help. I am suggesting that a more
> complicated version of EDC might be needed than that assumed for LRM,
> and the benefits achieved might not be as great as initially expected.
>
> Regards,
>
> Mike Dudek
> Director Transceiver Engineering
> Picolight Inc
> 1480 Arthur Avenue
> Louisville
> CO 80027
> Tel 303 530 3189 x7533.
> mike.dudek@picolight.com <mailto:mike.dudek@picolight.com>
>
> ------------------------------------------------------------------------
>
> *From:* Roger Merel [mailto:rmerel@GMAIL.COM]
> *Sent:* Friday, December 22, 2006 1:16 PM
> *To:* STDS-802-3-HSSG@listserv.ieee.org
> <mailto:STDS-802-3-HSSG@listserv.ieee.org>
> *Subject:* Re: [HSSG] <HSSG-FO> Fiber Optic Ad Hoc Teleconference
> 12/18/2006
>
>
> All,
>
> To the extent that dispersion penalties adversely affect the link
> budget (even if the link works) for 1550nm 10G (or 20G/25G) using
> DMLs, one can consider using EDC to reclaim some of those penalties.
> EDC at 10G is readily available, but yet not presently available at
> 20/25G.
>
> -Roger
>
> ------------------------------------------------------------------------
>
> *From:* Tsumura, Eddie [mailto:etsumura@EXCELIGHT.COM]
> *Sent:* Friday, December 22, 2006 1:57 PM
> *To:* STDS-802-3-HSSG@listserv.ieee.org
> <mailto:STDS-802-3-HSSG@listserv.ieee.org>
> *Subject:* Re: [HSSG] <HSSG-FO> Fiber Optic Ad Hoc Teleconference
> 12/18/2006
>
> Hi everyone,
>
> I would like to propose the change of Reach (Technical) Feasibility
> Table what Chris created.
>
> Please see attached file.
>
> We confirmed that 1550nm DML is possible to support 10G-10km/40km.
>
> Also, it might be possible to support 20G/25G-10km if only dispersion
> penalty is a bottleneck.
>
> My proposed change is as follows.
>
> 1) 10km, 1550nm, 10G DML: change to "yes" from "maybe"
>
> 2) 40km, 1550nm, 10G DML: change to "yes" or "maybe" from "no"
>
> 3) 10km, 1550nm, 20G/25G DML: change to "maybe" from "no"
>
> Any comments are welcomed for me.
>
> Have a happy holiday!
>
> Eddie
>
> **Eddie Tsumura**
>
> Vice president of Engineering and Marketing
>
> **Excelight Communications** (A Sumitomo Electric Company)
>
> 4021 Stirrup Creek Drive
>
> Suite 200
>
> Durham, NC 27703
>
> Phone 919-361-1634
>
> Fax 919-361-1619
>
> etsumura@excelight.com <mailto:etsumura@excelight.com>
>
> ------------------------------------------------------------------------
>
> *From:* Dove, Dan [mailto:dan.dove@HP.COM]
> *Sent:* Monday, December 18, 2006 5:46 PM
> *To:* STDS-802-3-HSSG@listserv.ieee.org
> <mailto:STDS-802-3-HSSG@listserv.ieee.org>
> *Subject:* [HSSG] <HSSG-FO> Fiber Optic Ad Hoc Teleconference 12/18/2006
>
> HSSG Members,
>
> We held our teleconference this morning but unfortunately, the bridge
> supplier I use had changed their PIN system and I was forced to send
> out a new bridge number at the last minute. I realize some people were
> unable to attend due to this occurrance, and I give you my apologies.
>
> I am going to provide the meeting notes below. If you see any need for
> correction to the notes, please send an email to dan.dove@hp.com
> <mailto:dan.dove@hp.com> and I will update the minutes before posting
> them on the HSSG-FOAH website. This will prevent multiple messages
> with corrections being sent onto the reflector, OK?
>
> Also, for all who are interested, I am calling for presentations at
> the January Interim. Those presentations should be specific to proving
> technical and economic feasibility for a single-mode 10Km link, and
> for a 100m multi-mode link. It is important to recognize that we are
> not trying to select a specific proposal at this time, but to
> demonstrate to > 75% of the HSSG and IEEE 802.3 that we have proven
> these things.
>
> Today's work was focused on single-mode only, so we should be sure to
> get multi-mode presentations on the table as well.
>
> Regards,
>
> Dan Dove
>
> Chairman, HSSG FO Adhoc
>
> ==============================================
>
> Meeting Notes:
>
> Attendees:
>
>
> Last
>
> First
>
>
>
> Employer
>
>
>
> Affiliation
>
>
>
> 12/18/2006
>
> Anslow
>
>
>
> Pete
>
>
>
> Nortel Networks
>
>
>
> Nortel Networks
>
>
>
> Y
>
> Clairardin
>
>
>
> Xavier
>
>
>
> Kotura
>
>
>
> Kotura
>
>
>
> Y
>
> Cole
>
>
>
> Chris
>
>
>
> Finisar
>
>
>
> Finisar
>
>
>
> Y
>
> Dove
>
>
>
> Daniel
>
>
>
> Dove Networking
>
>
>
> ProCurve Networking by HP
>
>
>
> Y
>
> Dudek
>
>
>
> Mike
>
>
>
> Picolight
>
>
>
> Picolight
>
>
>
> Y
>
> Fischer
>
>
>
> Thomas
>
>
>
> Siemens
>
>
>
> Siemens
>
>
>
> Y
>
> Jaeger
>
>
>
> John
>
>
>
> Infinera
>
>
>
> Infinera
>
>
>
> Y
>
> Jiang
>
>
>
> Wenbin
>
>
>
> JDSU
>
>
>
> JDSU
>
>
>
> Y
>
> Patel
>
>
>
> Sashi
>
>
>
> Foundry Networks
>
>
>
> Foundry Networks
>
>
>
> Y
>
> Pepeljugoski
>
>
>
> Petar
>
>
>
> IBM
>
>
>
> IBM
>
>
>
> Y
>
> Song
>
>
>
> Steve
>
>
>
> Exelight
>
>
>
> Exelight
>
>
>
> Y
>
> Tatah
>
>
>
> Karim
>
>
>
> Cray
>
>
>
> Cray
>
>
>
> Y
>
> Tsumura
>
>
>
> Eddie
>
>
>
> Exelight
>
>
>
> Exelight
>
>
>
> Y
>
> Discussed the new table additions and corrections made since last
> teleconference;
>
> Discussed Chris Cole Presentation;
>
> 10G Rows:
>
> Matt: Discrete devices available, extrapolation not necessarily valid
>
> For example, EMLs tend to be larger, take up more wafer space
>
> Chris: Another thing not captured, 10G DML @ 1550 not considered in
> green but maybe we should take it off the study list because hard to
> build as monolithic array
>
> Xaviar: Would like to avoid taking things off at this point. Would
> like to present work showing it's a viable alternative.
>
> Chris: DML at 1550 gonna work at 40k?
>
>
> Xaviar: Objective is 10K, we need to keep. Not captured, whether CWDM
> or DWDM in that column.
>
> Mike D: CWDM being considered for all or just 1310?
>
> Chris: Does not address this distinction. Slide 4 addresses some of
> this, but slide 3 is trying to capture wavelength and transmitter
> type. This table does not capture "optimum" or "implementation
> complexity".
>
> 20G Rows:
>
> Chris discusses his perspective. Nobody argued with his position that
> 20G 10K DML not possible.
>
> 50G Rows:
>
> General: Would be nice to have 40K and 10K leverage common approach.
> Green applied where it appears to be possible.
>
> Marc Lucent: Main objective regarding DQPSK at 50 / 1310 is dispersion?
>
> Chris: Yes, the implementation for 50G 1550 looks large and therefore
> does not seem LAN oriented. At 1310 makes better sense.
>
> Marc: For 40Km, 1550, might make better sense for this longer reach.
>
> Chris: Yes, the breakpoints for 10G are 1310 DML and 1550 EML, so this
> is consistent. For us, its possible to set the breakpoint at 40-80Km.
> Question is, do we really want to add the cost of this technology for
> 40Km.
>
> Marc: Chromatic dispersion your primary concern?
>
> Chris: Looking forward to presentations on this subject.
>
> Robert Lingle: Main Point to have a pluggable in a small form factor
> and dispersion compensation may prohibit this.
>
> Chris, yes.
>
> Peter: Do you see an activity to standardize a form factor for a module?
>
> Chris: yes. Likely done outside IEEE.
>
> Peter: Would larger group oppose having different form factors?
>
> Matt: With regard to 20/25G DML, been looking at 1310...wonder, at
> 10K, what were the dispersion numbers that led you to your conclusion?
>
> Dan: My notes missed some of the content on this part..it was pretty
> dense..sorry;
>
> Chris: Is there a breakpoint between 20G and 25G on DML?
>
> Chris: Could provide an EML spec as long as it was possible to reduce
> cost in future.
>
> Frank: We are dealing with tech feasibility, we need to consider cost
> too. For example, with 25G, you cannot do arrays, it creates a big
> cost issue.
>
> Chris: yes, this is accurate. We need an economic feasibility table.
>
> Discussion of page 4:
>
> Copying conclusions from page 3 and modified format to make things
> more visible;
>
> Why did 1550 get eliminated? Concluded DMLs in the timeframe not
> feasible due to dispersion.
>
> This conclusion has been challenged and presentations may come in to
> address that.
>
> For EML 20G 40Km is not leveragable.
>
> Matt: Agrees with earlier comment to allow for 1st gen to focus on EML
> with longterm DML targets... maybe able to collapse rows 2,3 and 4,5
> together.
>
> Chris: Would be good to come up with an approach that allows this to
> happen.
>
> Chris: We can add to the format additional proposals per email and
> discussion.
>
> Mike: Is the intent of the cooling and grid columns to be 1 for 1 across?
>
> Chris: If no cooling, drift will be larger and thus they should be
> cited independently.
>
> Chris: Semi-cooling is less precise than cooling, but offers a lower
> cost means..for example heating to ensure minimum temps are eliminated.
>
> No more comments on presentation. Some discussion on the upcoming
> meeting and it was stated by the chair that we should build
> presentations for January's interim rather than divide our attention
> on another phone conference.
>
> Teleconference closed.
>