Colleagues
Perhaps, I can point this out before Ryan.
It seems to me that many pcb layouts will present sufficient challenges
such that a direct connection between the host IC and pluggable module will not
be supported and a signal conditioner will be needed between the host IC and
module. This means that for reasons other than extending the optical link
reach, the means to extend the optical link reach are in place at least for
these situations. All that is needed then is a way to permit the
installer to take advantage of the optical link extension that an external signal
conditioner, adjacent to but not included in the module, provides. It
will be frustrating to have all the pieces paid for and in place and not be
able to take advantage of the extended link reach that they offer.
By the way, a similar situation exists
with respect to using FEC.
Regards,
John
From: Gourgen
Oganessyan [mailto:gourgen@xxxxxxxxxxx]
Sent: Wednesday, July 09, 2008
8:02 PM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3BA] XR ad hoc
Phone Conference Notice
Petar,
Well, sadly that’s what has been
happening in the 10G world, people are forced to amortize the cost of 300m reach
(LRM), while in reality the number of people who need 300m is close to 0.
That’s why I am strongly in support
of your approach of keeping the 100m objective as primary goal.
Frank, OM4 can add as much cost as it
wants to, the beauty is the added cost goes directly where it’s needed,
which is the longer links. Alternatives force higher cost/higher power
consumption on all ports regardless of whether it’s needed there or not.
Gourgen Oganessyan
Quellan Inc.
Phone: (630)-802-0574 (cell)
Fax: (630)-364-5724
e-mail: gourgen@xxxxxxxxxxx
From: Petar
Pepeljugoski [mailto:petarp@xxxxxxxxxx]
Sent: Wednesday, July 09, 2008
7:51 PM
To:
STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3BA] XR ad hoc
Phone Conference Notice
Frank,
If I
interpret correctly, you are saying that all users should amortize the cost of
very few who need extended reach.
We
need to be careful how we proceed here - we should not repeat the mistakes of
the past if we want successful standard.
Regards,
Peter
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
|
From:
|
Frank Chang <ychang@xxxxxxxxxxx>
|
|
To:
|
STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
|
|
Date:
|
07/09/2008 10:29 PM
|
|
Subject:
|
Re: [802.3BA] XR ad hoc Phone Conference Notice
|
Hi Jeff;
Thanks for your comment. You missed one critical point that there
is cost increase from OM3 to OM4. If you take ribbon cable cost in perspective,
OM4 option is possibly the largest of the 4 options.
Besides, the use of OM4 requires to tighten TX specs which
impact TX yield, so you are actually compromising the primary goal.
Frank
From: Jeff Maki
[mailto:jmaki@xxxxxxxxxxx]
Sent: Wednesday, July 09, 2008 7:02 PM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3BA] XR ad hoc Phone Conference Notice
Dear
MMF XR Ad Hoc Committee Members,
I
believe our current objective of “at least 100 meters on OM3 MMF”
should remain as a primary goal, the baseline. Support for any form of
extended reach should be considered only if it does not compromise this primary
goal. A single PMD for all reach objectives is indeed a good starting
premise; however, it should not be paramount. In the following lists are
factors, enhancements, or approaches I would like to put forward as acceptable
and not acceptable for obtaining extended reach.
Not
Acceptable:
1.
Cost increase for the baseline PMD (optic) in order to obtain greater than
100-meter reach
2. EDC
on the system/host board in any case
3. CDR
on the system/host board as part of the baseline solution
4. EDC
in the baseline PMD (optic)
5. CDR
in the baseline PMD (optic)
Acceptable:
1. Use
of OM4 fiber
2.
Process maturity that yields longer reach with no cost increase
In
summary, we should not burden the baseline solution with cost increases to meet
the needs of an extended-reach solution.
Sincerely,
Jeffery
Maki
————————————————
Jeffery
J. Maki, Ph.D.
Principal
Optical Engineer
Juniper
Networks, Inc.
1194 North Mathilda Avenue
Sunnyvale, CA
94089-1206
Voice
+1-408-936-8575
FAX +1-408-936-3025
www.juniper.net
jmaki@xxxxxxxxxxx
————————————————