do you have any data that would support
your suggestion Paul?
Jonathan
tel: 1 408 524 5110
e-mail: jking@bigbearnetworks.com
fax: 1 408 739 0568
Jonathan King
Director, Optical Systems
BigBear Networks
345 Potrero Avenue
Sunnyvale, CA 94085
-----Original Message-----
From: Paul Kolesar
[mailto:PKOLESAR@SYSTIMAX.COM]
Sent: Thursday, August 19, 2004
8:30 PM
To:
STDS-802-3-10GMMF@listserv.ieee.org
Subject: Re: [10GMMF] 62MMF
connector loss and draft test link config
David,
thanks
for this work. The model I have for 62.5 agrees with your analysis for
the steady state launch condition. Please confirm that in your model the
steady state condition represents a 70/70 launch (i.e. 70% of maximum core
diameter and 70% of maximum NA).
I
have a comment regarding the 7 um limit. The 7 um value was chosen for the OM3
work because it represented 0.5 dB for 50 um fiber under steady state
conditions. The remaining 0.25 dB needed to reach the 0.75 dB limit was
allotted to mechanisms other than lateral offset. The equivalent offset
for 62 um fiber is 9 um from your graph. Thus connectors need to be of
tighter tolerance for 50 um fiber than for 62 um fiber. As product lines
of cabling vendors in North America and other parts of the world have shifted
to include a larger mix of 50 um fiber, the tolerance for connectors needed to
be tightened to maintain good performance. Fortunately progress in
connector technology permitted this. The result is that over time
connectors have gotten better. This leads to an interesting issue when
dealing with legacy plant. The older plant likely has poorer connectors due to
both tolerance and wear. I think this leads to a need for considering
different values for legacy 50 and 62 um plants. To address these
considerations, I would suggest that the limit for 62 um fiber be set at 9 um
and that for 50 set at 7 um.
Regards,
Paul Kolesar
SYSTIMAX® SOLUTIONS
1300 East Lookout Drive
Richardson, TX 75082
Phone: 972.792.3155
Fax: 972.792.3111
eMail: pkolesar@systimax.com
|
|
David Cunningham
<david_cunningham@AGILENT.COM>
Sent
by: owner-stds-802-3-10gmmf@listserv.ieee.org
08/18/2004 02:24 PM
Please
respond to "IEEE 802.3aq 10GBASE-LRM"
|
To: STDS-802-3-10GMMF@listserv.ieee.org
cc: (bcc: Paul F
Kolesar/CommScope)
Subject: [10GMMF] 62MMF
connector loss and draft test link config
|
Dear
All,
As promised on todays Fiber Channel Ad Hoc I
attach a PDF file containing the following information:
* My calculated graphs of connector loss versus
offset for overfilled launch, steady state launch and 23 um offset single mode
launch.
* The agreed draft of the worst-case test
configuration for channel time variation measurements with comments from our
call to document our reasoning behind the chosen configuration.
Regards,
David