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Re: [HSSG] Reach Objectives



Why? Because the debate has been had repeatedly for every generation of technology that has come and gone and will probably be had for every generation that is yet to come. The underlying technology changes and that will change the answer in terms of where the breakpoints lie between different technologies. Another big thing that changes is the set of people in the room and different groups will always come up with different answers based on their different perspectives. But one thing that I believe changes very little from generation to generation is the reach between different boxes. My comments are mostly influenced by my perspective on telecommunications applications, but I suspect the same thing mostly applies to datacenters too. The shape of the histogram of the number of links plotted vs. the length of those links probably stays roughly constant. Where the breakpoints are of greatest cost effectiveness between different fundamental technologies will move depending on bit rate, but to the first order the number of PMDs probably remains roughly equal.

 

My thoughts are further influenced by my expectation that for multi-km reaches we’ll likely end up with Nx10G (or N/2x20G) WDM PMDs. The smaller the N and the larger the bit rate, the more the breakpoints are likely to move around.

 

Drew

_____________________________

 

Drew Perkins

Chief Technology Officer

Infinera Corporation

1322 Bordeaux Drive

Sunnyvale, CA  94089

 

Phone:  408-572-5308

Cell:       408-666-1686

Fax:        408-904-4644

Email:    dperkins@xxxxxxxxxxxx

WWW :  http://www.infinera.com

 

_____________________________

 


From: Brad Booth [mailto:bbooth@xxxxxxxxxxxxx]
Sent: Tuesday, August 22, 2006 10:56 AM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [HSSG] Reach Objectives

 

Excuse my ignorance, but why?  When 10G started, this was an important debate.  If they had stuck with the number of PMDs in 802.3z, then there would have only been two PMDs.  The study group needs to define the markets that it wants to satisfy, and only then when the study group becomes a task force can the group decide on the actual number of PMDs required.

 

Thanks,

Brad

 


From: Drew Perkins [mailto:dperkins@xxxxxxxxxxxx]
Sent: Tuesday, August 22, 2006 10:45 AM
To: Brad Booth; STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: RE: [HSSG] Reach Objectives

I have a simple proposal to save everyone a lot of time. Let’s make the baseline plan to stick with exactly the same number of PMDs with exactly the same reaches as 10GbE. They have all been developed to fit someone’s requirements. We should have a very high hurdle to eliminate any of these or add to them.

 

Drew

_____________________________

 

Drew Perkins

Chief Technology Officer

Infinera Corporation

1322 Bordeaux Drive

Sunnyvale, CA  94089

 

Phone:  408-572-5308

Cell:       408-666-1686

Fax:        408-904-4644

Email:    dperkins@xxxxxxxxxxxx

WWW :  http://www.infinera.com

 

 

_____________________________

 


From: Brad Booth [mailto:bbooth@xxxxxxxxxxxxx]
Sent: Tuesday, August 22, 2006 10:19 AM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [HSSG] Reach Objectives

 

The 10km vs. 2km debate occurred in 802.3ae.  It was determined that the solution for 2km was virtually the same as that for 10km; therefore, the task force felt it would be better to select only one of those reaches and 10km was it.  If there is a desire for 2km and 10km reaches in HSSG, then in my humble opinion, those wishing to support will need to bring justification forward as to why the study group should consider possibly increasing the number of PHYs.

 

Cheers,

Brad

 


From: Frank Chang [mailto:ychang@xxxxxxxxxxx]
Sent: Tuesday, August 22, 2006 9:19 AM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [HSSG] Reach Objectives

John/Petar;

 

I agree datacenter for up to 100m. How about 10GigE LR disctance (10km) or campus 2km discussed earlier?

 

Frank

-----Original Message-----
From: Petar Pepeljugoski [mailto:petarp@xxxxxxxxxx]
Sent: Tuesday, August 22, 2006 6:02 AM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [HSSG] Reach Objectives


John,

I believe that the Data Center distances should be 100m and 300m.

Petar Pepeljugoski
IBM Research
P.O.Box 218 (mail)
1101 Kitchawan Road, Rte. 134 (shipping)
Yorktown Heights, NY 10598

e-mail: petarp@xxxxxxxxxx
phone: (914)-945-3761
fax:        (914)-945-4134

John DAmbrosia <jdambrosia@xxxxxxxxxxxxxxxxxxx>

08/22/2006 12:37 AM

Please respond to
John DAmbrosia <jdambrosia@xxxxxxxxxxxxxxxxxxx>

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[HSSG] Reach Objectives

 

 

 




All,
We have had some conversation on the reflector regarding reach objectives.  Summarizing what has been discussed on the reflector I see the following –
 
Reach Objectives
Long-Haul   --> 100+ km
Metro       --> 10+ km
Data Center --> 50m & 300m
 
Data Center Reach Segregation
Intra-rack
Inter-rack
Horizontal runs
Vertical risers
 
Use this data to identify a single low-cost solution that would address a couple of the reach objectives
 
Other Areas
During the course of the CFI there were individuals who wanted Backplane Applications kept in for consideration, but I have not heard any further input in this area.  Are there still individuals who wish to propose Backplane as an objective?
 
John