In HPC and Datacenter environment one
can often find (and needs) distances that are closer to 100m. Some of the
optical solutions might have the same specs for 50m/100, particularly since
we plan on using only OM3. Unless the line rate becomes much higher than
10 Gb/s, the difference in penalties and attentuation is minimal, so we
should go with the optimal solution (cost/distance).
Regards,
Peter
Petar Pepeljugoski
IBM Research
P.O.Box 218 (mail)
1101 Kitchawan Road, Rte. 134 (shipping)
Yorktown Heights, NY 10598
Please respond to
Brad Booth <bbooth@xxxxxxxxxxxxx>
To
STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
cc
Subject
Re: [HSSG] Reach Objectives
I agree with Geoff. As mentioned,
the 802.3an task force worked very hard to achieve the 100m reach. The
10GBASE-T 100m reach was driven by the horizontal cabling specification,
not what the typical deployment was in a data center.
Cheers,
Brad
From: Geoff Thompson [mailto:gthompso@xxxxxxxxxx]
Sent: Tuesday, August 22, 2006 8:55 AM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [HSSG] Reach Objectives
Roger-
At 03:47 AM 8/22/2006 , Roger Merel wrote:
Agree with Drew. Have
a few additional comments on other reachs:
For reach objectives, we should start with customer based needs (for broad
market potential) and only amend if an obvious technical limitation with
compelling economics can t readily meet the broad customer need.
Specifically:
- Long Reach probably should be set at 80km rather than 100km (as this
is the common hut-to-hut amplifier spacing in telecom)
- While 50m does serve a useful portion of the market (smaller datacenters
and/or the size of a large computer cluster), it is somewhat constraining
as I ve been lead to understand that the reach needed in larger datacenters
is continuing to out-grow the 100m meter definition but the 100m definition
at least serves the customer well. Certainly 10G-BaseT worked awfully
hard to get to 100m (for Datacenter interconnect).
I wouldn't attach a lot of creedence to the 10GBASE-T goal for 100 meters.
It was, I believe, mainly driven by the traditional distance in horizontal
(i.e. wiring closet to desktop) distances rather than any thorough examination
of data center requirements.
Geoff
- For both in-building reaches
(50m & 300m; or 100m & 300m), the bigger issue which affects the
PMD is the loss budget arising from the number of patch panels. The
shorter / datacenter reach should include a budget for 1 patch panel. The
longer / enterprise reach should include a budget for 2 patch panels (one
in the datacenter and 1 in the remote switch closet).
From: Drew Perkins [mailto:dperkins@xxxxxxxxxxxx]
Sent: Tuesday, August 22, 2006 1:24 AM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [HSSG] Reach Objectives
John,
I suggest dividing Metro into Metro Short Reach at 10 km (equivalent application
to 10GBASE-LR) and Metro Intermediate Reach at 40 km (equivalent application
to 10GBASE-ER).
From: John DAmbrosia [mailto:jdambrosia@xxxxxxxxxxxxxxxxxxx]
Sent: Monday, August 21, 2006 9:38 PM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: [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?