Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

Re: [802.3_100GNGOPTX] SMF and MMF Ad Hoc meetings: MMF objective



Hi Steve,

Your response illustrates my point if one examines the cost situation a bit closer.  It is not sufficient to take a broad brush view that the SM optics will retain a step function cost increase relative to MM optics, because the magnitude of that step is critically important.  As I tried to show in my contribution at the last meeting in Newport Beach, the optimal reach objective for MM changes as a function of that step size.  When that SM step is about 5x there is parity in total cost (i.e. cost of all optics plus cost of all cabling needed to build data center switch-to-switch channels) between MM optics with a capability of 100 m and MM optics with a capability of 150 m.  In other words we could choose either a 100 m objective or a 150 m objective and get nearly the same total cost outcome.  If that step is larger than 5x, then a MM reach longer than 100 m is needed.  If that step is less than 5x then a MM reach of 100 m is optimal.  

 

To me it not a question of if the SM cost step will be reduced to 5x from its current magnitude, for all prior Ethernet SM solutions have seen this occur.  It is a question of when.  If the answer to “when” is projected to be so far into the future that LR4 remains a hindrance to broad market potential during the time when the market is projected to broaden, then that indicates we either need another SM PMD with cost structures that can remove that hindrance, or we need a MM objective that covers a greater portion of the longer length channels than can be addressed with a 100 m solution. 

 

So for me its all about understanding the various SM solution cost projections over time.  Give me that information and I can make a sufficiently informed determination on the optimal MM reach objective.

 

Regards,

Paul

 


From: Trowbridge, Stephen J (Steve) [mailto:steve.trowbridge@xxxxxxxxxxxxxxxxxx]
Sent: Friday, February 24, 2012 8:14 AM
To: Kolesar, Paul; STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx
Subject: RE: [802.3_100GNGOPTX] SMF and MMF Ad Hoc meetings: MMF objective

 

Hi Paul,

I don’t think it is nearly so clear that you should decide SM first.

 

If there existed a SM solution that was cost-competitive with a MM solution at some reach, it would be a game changer, and those developing MM solutions would surely like to know if the game will change before getting too far down the path. But most seem to believe that the game will not change, and even if it did, it is hard to prove because it is difficult to compare relative costs of dissimilar technologies.

 

Most still seem to believe (in spite of the interesting technology from Opnext) that there will be a significant step function from MM to SM that will keep people from wanting to use it in data centers. Furthermore, if you need a different cable type, for example, for a 70m link than you need for a 100m link, that creates its own kind of problem.

 

So if the game does not change, then SR4 needs to try to address most, if not all, of the reach currently addressed by SR10. If it turns out not to be technically or economically feasible to do that (e.g., if you could only get 60 or 70m out of the beast within reasonable cost, size and power), then if SM is to replace MM above that reach, it needs to get down to a cost to compete with an SR10 with a reverse gearbox. Even if SM does this, it isn’t clear they will get all of that market because of a likely reluctance to mix cable types in the data center – maybe they are happier to use SR10 with a reverse gearbox to reuse their existing cabling.

Regards,

Steve

 

From: Kolesar, Paul [mailto:PKOLESAR@xxxxxxxxxxxxx]
Sent: Friday, February 24, 2012 6:49 AM
To: STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_100GNGOPTX] SMF and MMF Ad Hoc meetings: MMF objective

 

Jonathan,

While I understand the desire to find a launching point for the discussion, this poll is approaching the problem in the wrong order because we need to know what the single-mode objective is first.  

 

A purpose of the Study Group is to set objectives that will allow us to establish cost-optimized 100GE.  One cannot logically pick cost-optimized MM objectives without first having framework around the SM optics that will be used to address channels with lengths that exceed the MM reach.  At this point, we have not even established if we will have a SM objective.  In other words, we don’t know if the existing LR4 will remain the only one, or if there will be another one added.  Only when the SM situation is established can we know the minimum capability that a new MM optic must fulfill to optimize cost.

 

I suggest that we first conduct such a poll for SM and use it to start the objective discussion in the SM ad-hoc.  If that produces solid results, then undertake the same endeavor for MM.

 

 

Regards,

Paul

 


From: Jonathan King [mailto:jonathan.king@xxxxxxxxxxx]
Sent: Thursday, February 23, 2012 8:13 PM
To: STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_100GNGOPTX] SMF and MMF Ad Hoc meetings: MMF objective
Importance: High

 

Dear all,

On the Feb 14th MMF ad hoc call , it seemed like we were  beginning to converge on a possible objective for MMF .

In the next meeting (Tuesday 28th Feb), I’d like to see if we can finalize a strawman MMF objective.  To that end I’ll prepare  a presentation which we can review  during the call which will include a strawman objective for review on the call, together with an overview of how it addresses the 5 criteria – to help get the best starting point for that discussion I’d like to get your responses to the questions below  questions:

 

The strawman objective will follow the wording in Anslow_01_0111

 

Define a 4-lane 100 Gb/s PHY for operation over OMX MMF with lengths up to at least Y m

 

 

1)      A reasonable MMF reach objective (i.e. the value of Y) would be

a.      100m

b.      Significantly less than 100m (what reach?)

c.       Significantly more than 100m  (what reach ?)

d.      decided in the task force

 

2)      The MMF type should be

a.      decided in the task force

b.      OM3

c.       OM4

d.      at least as good as OM4

 

Please send your responses to me directly at:  jonathan.king@xxxxxxxxxxx

I will collate and report the results but will not reveal any individual’s responses.

If you feel uncomfortable expressing an opinion, say so and I’ll note that.

 

To  repeat, this is not a formal poll or vote, just intended to give us the best starting point for discussion on Tuesday.

Please send your responses as soon as possible, and at least by close of business on Monday 27th Feb, 2012

Many thanks !

 

Jonathan King

MMF ad hoc chair, Next Gen 100G Optics

 

From: Anslow, Peter [mailto:panslow@xxxxxxxxx]
Sent: Wednesday, February 22, 2012 2:10 AM
To: STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx
Subject: [802.3_100GNGOPTX] SMF Ad Hoc and MMF Ad Hoc meetings

 

Hi,

 

Following on from the meetings on 14 February, Jonathan and I are planning to hold an SMF Ad Hoc meeting immediately followed by an MMF Ad Hoc meeting (1 hour each) starting at 8:00 am Pacific on Tuesday 28 February.

 

If you would like to present a contribution at the SMF ad hoc, please send it to me and for the MMF ad hoc, send it to Jonathan.

 

Peter Anslow from Ciena has invited you to join a meeting on the Web, using WebEx. Please join the meeting 5-10 minutes early so we may begin on time.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Topic: "SMF Ad Hoc followed by MMF Ad Hoc"

Date & Time: Tuesday, 28 February 2012 at 16:00, GMT Time (London, GMT)

To join web meeting click here: https://ciena.webex.com/ciena/j.php?ED=136667227&UID=0&PW=NMGZjOWUwNDM2&RT=MTgjMjE%3D

Meeting password: IEEE (please note passwords are case sensitive)

Teleconference: Call-in number:

+44-203-4333547  (United Kingdom)

4438636577  (United States)
2064450056  (Canada)

Conference Code: 207 012 5535

Meeting number: 683 690 763

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Additional Notes:

- To add this meeting to your calendar program click the following link, or copy the link and paste it into your Web browser: https://ciena.webex.com/ciena/j.php?ED=136667227&UID=0&ICS=MI&LD=1&RD=18&ST=1&SHA2=zxju/MpyUhnp7ROB7hR78ViLpXBupiLpj4OEPm0zSJ8=&RT=MTgjMjE%3D

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Australia, Brisbane :        0730870163

Australia, Melbourne :   0383380011

Australia, Sydney :           0282386454

Austria, Vienna :               01253021727

Belgium, Brussels :          028948259

Bulgaria, Sofia : 024917751

Canada, All Cities :           2064450056

China, All Cities Domestic :           8008706896

China, All Cities Domestic :           4006920013

Czech Republic, Prague :               228882153

Denmark, Copenhagen :               32727639

Estonia, Tallinn :                6682564

Finland, Helsinki :             0923193023

France, Paris :    0170375518

Germany, Berlin :             03030013082

Germany, Frankfurt :     06924437355

Hong Kong, Hong Kong :               85230730462

Hungary, Budapest :       017789269

India, Bangalore :             08039418300

India, Chennai - Primary :             04430062138

India, Mumbai :                02239455533

India, New Delhi :            01139418310

Ireland, Dublin :                015269460

Israel, Tel Aviv : 37630760

Italy, Milan :       0200661900

Japan, Tokyo :   0345808383

Korea (South), All Cities :              0264903634

Latvia, Riga :       66013622

Lithuania, Vilnius :            52055461

Luxembourg, Luxembourg :        20881245

Malaysia, Kuala Lumpur :              0348190063

Netherlands, Amsterdam :          0207946527

New Zealand, Auckland :              099291734

Norway, Oslo :  21033950

Poland, Warsaw :             223070121

Romania, Bucharest :     318144966

Russian Federation, Moscow :   4992701688

Singapore, All Cities :      6568829970

Slovak Republic, Bratislava :         0233418490

Slovenia, Ljubljana :        016003971

Spain, Barcelona :            935452633

Spain, Madrid :  911146624

Sweden, Stockholm :     0850512711

Switzerland, Bellinzona :               0912611463

United Kingdom, All Cities :         08443386571

United Kingdom, All Cities :         02034333547

United States, All Cities :               4438636577

Vietnam, Ho Chi Minh : 84838012419

 

Regards,

Pete Anslow | Senior Standards Advisor
43-51 Worship Street | London, EC2A 2DX, UK
Direct +44 2070 125535 |