While I am sympathetic with your view
of the objectives, I disagree and oppose changing the current reach objective
of 100m over OM3 fiber.
From my previous standards experience,
I believe that all the difficulties arise in the last 0.5 dB or 1dB of
the power budget (as well as jitter budget). It is worthwhile to ask module
vendors how much would their yield improve if they are given 0.5 or 1 dB.
It is responsible for most yield hits, making products much more expensive.
I believe that selecting specifications
that penalize 95% of the customers to benefit 5% is a wrong design point.
You make another point - that larger
data centers have higher bandwidth needs. While it is true that the bandwidth
needs increase, you fail to mention is that the distance needs today are
less than on previous server generations, since the processing power today
is much more densely packed than before.
I believe that 100m is more than sufficient
to address our customers' needs.
P.O.Box 218 (mail)
1101 Kitchawan Road, Rte. 134 (shipping)
Yorktown Heights, NY 10598
I am a consultant with over 25 years experience in
infrastructure design and data center relocations including in excess of
data centers totaling 2 million+ sq ft. I am currently engaged in
center projects for one of the two top credit card processing firms and
of the two top computer manufacturers.
I'm concerned about the 100m OM3 reach objective, as it does not cover
adequate number (>95%) of backbone (access-to-distribution and
distribution-to-core switch) channels for most of my clients' data centers.
Based on a review of my current and past projects, I expect that a 150m
larger reach objective would be more suitable. It appears that some
data presented by others to the task force, such as Alan Flatman's Data
Centre Link Survey supports my impression.
There is a pretty strong correlation between the size of my clients' data
centers and the early adoption of new technologies such as higher speed
connectivity. It also stands to reason that larger data centers
higher bandwidth needs, particularly at the network core.
I strongly encourage you to consider a longer OM3 reach objective than
J&M Consultants, Inc
co-chair BICSI data center standards committee
vice-chair TIA TR-42.6 telecom administration subcommittee
vice-chair TIA TR-42.1.1 data center working group (during development
USTAG representative to ISO/IEC JTC 1 SC25 WG3 data center standard adhoc