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RE: MMF PMD Selection

Dear Wenbin,
Not so sure about your comment on the 850nm CWDM PMD being the lowest cost
solution.  Our studies show that in the long run, the 850nm serial PMD would
be the lowest cost, and more importantly the simplest solution for
application #3.....assuming the equalization scheme turns out to work well.
It also fits well into the current PMD selection scheme, i.e. serial
operation at 1550nm, 1310nm, ------> 850nm.
Chris Simoneaux

-----Original Message-----
From: Wenbin Jiang [mailto:wbjiang@xxxxxxxxxx]
Sent: Wednesday, July 19, 2000 2:46 PM
To: David Martin; stds-802-3-hssg
Subject: Re: MMF PMD Selection

I supported the 3-PMD because I firmly believe that less the number of PMDs
we have to support, 
higher the volume for each PMD, and the lower the cost will be.
The working group has voted for 1550 nm and 1310 nm serial to support
Application 1 and 2.  If the 
equalization scheme turns out to work well, the short wavelength 850 nm
4-CWDM should be the 
lowest cost solution that will address Application 3.  We will still end up
with 3-PMD. What about
eye safety? Either OFC or the new eye safety standard will address it.
Wenbin Jiang

----- Original Message ----- 
From: David Martin <mailto:dwmartin@xxxxxxxxxxxxxxxxxx>  
To: stds-802-3-hssg <mailto:stds-802-3-hssg@xxxxxxxx>  
Sent: Wednesday, July 19, 2000 10:41 AM
Subject: MMF PMD Selection


In the interest of making progress on the MMF PMD selection, and in 
response to Bill's request for system vendor input, I'll paint a bright 
red target on myself. Here goes. 

Consider the following four distinct applications: 

1.	Dark fiber/SMF runs up to 40km & WAN interconnect (metro) 

2.	Dark fiber/SMF runs up to 10km & WAN interconnect (campus backbone) 

3.	MMF horizontal/vertical runs up to 100/300m (in-building) 

4.	New fiber (any type: ribbon, MMF, SMF) runs up to 300m

It is easiest to explain to customers what to deploy when there is a PMD 
positioned to match each application (or ideally one that does all).  I
serial 1550 for app-1, serial 1310 for app-2, 1300 WWDM for app-3 and 
left app-4 for the OIF VSR work activity (as we don't have a general intra- 
office interconnect objective, but could adopt/adapt their results in a

So why pick 1300 WWDM for app-3? My thinking: 

a.	It is the only solution which addresses up to 300m for all installed

	That is really the end of the rationale. However, considering cost

b.	1300 VCSELs are supposedly only 6 months away (or up to 6 years 

away depending on the source), which should make 1300 WWDM cost 
competitive with 850 VCSEL WWDM. 

Now I'll duck & cover. 


David W. Martin 
Nortel Networks 
+1 613 765-2901   
+1 613 763-2388 (fax) 
 <mailto:dwmartin@xxxxxxxxxxxxxxxxxx> dwmartin@xxxxxxxxxxxxxxxxxx 


	BM__MailData-----Original Message----- 
From:   Bill Wiedemann [SMTP:billw@xxxxxxxxxxx] 
Sent:   Monday, July 17, 2000 9:34 PM 
To:     stds-802-3-hssg 
Subject:        RE: what's next ? 

	Jonathan, Thanks for your clarification on expectations for the
meeting in September. 

	I think it would be very helpful to have a discussion as to the
vendors desires. 

	For example their interest in the current candidates for the 100
meter and 
300 meter objectives. 1300WWDM, 850CWDM, 850 serial. 

	What they would "need" to see/understand for these to gain their
and/or why they never will support one or all of these.  My reason for 
initiating this is that it will be very difficult to get any of these 
approved unless we meet their expectations. I hope any of these aren't 
approved as the lesser of evils. 

	Regarding 850CWDM we are planning to make first implementations with
SC moving to LC with small form factors.  Our expectation is that small form

factor with LC could be available a year from today.  First size will be 
GBIC, electrical interface can be XGMII or XAUI for first implementations. 
Should we pursue equalization for 850CWDM to reach 300 meters over legacy 
62.5 um fiber? 

	We have had initial discussions with Brad Booth and David Cunningham
to be 
sure that the clauses for WDM implementations keep up with the current 
progress on serial clauses. 

	Bill Wiedemann 
925-560-1610  X169