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Geoff and Bruce, I don’t think the car
story is a valid
analogy. As we go from 10GbE to 100GbE, there is an
evolutionary transition in infrastructure – a larger portion of the link
distance must and will be cost-effectively covered by MM fiber, but the 802.3ba
objectives don’t reflect this. For 10GbE 10G-T, 802.3an had an objective to
support up to 55m (class E) and 100m (class F) on copper. http://ieee802.org/3/an/public/mar04/agenda_1_0304.pdf But for 100GbE 802.3ba we now have an objective
for 10m on copper http://ieee802.org/3/ba/public/jul08/agenda_01_0708.pdf Thus for 100GbE the 10-100m length must now be
covered by fiber. This can be done in the most cost-effective way by taking the
OM3 fiber and 850nm lasers used for 10GbE for 100-300m applications and
streamlining them for this application. This is implicit in the existing MM
objective. The full capability of 10GbE 850nm VCSELS and OM3 fiber is not
needed for most if not all of this length range at 100GbE, since they were
designed for 300m in 802.3ae, and cost reduction opportunities exist. However, a portion of the 100-300m range covered
by OM3 fiber in 10GbE will still be needed for 100GbE applications in data
centers. Fiber suppliers such as In analyzing the distribution of lengths in data
centers and high performance computing environments, it is a fact many of the
short links are currently copper. It is a mistake for us to think
that because the shorter lengths will now be MM fiber, that there is no need
for the longer lengths currently supplied. This mistake is an artifact of
how the data is being presented. It is absolutely contrary to the interests
of the end users for 802.3ba to neglect the 100-150m length segment with a
simple low-cost OM3 MM solution. From: Bruce Tolley
[mailto:btolley@xxxxxxxxxxxxxx] Geoff and Steve, For customers wanting TP links further
than 100 meters, I thought we pointed them to ISO 11801 and TIA568B which
recommend fiber :)) for such runs. Bruce From: Geoff
Thompson [mailto:gthompso@xxxxxxxxxx] At 06:35 PM 8/25/2008 , What should we tell our customers who have
link lengths longer than 100m and want (or require) a standardized solution?
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