Bruce, I don’t think the car
story is a valid
As we go
from 10GbE to 100GbE, there is an
evolutionary transition in infrastructure – a larger portion of the
distance must and will be cost-effectively covered by MM fiber, but the
objectives don’t reflect this.
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
100GbE 802.3ba we now have an objective
for 10m on copper http://ieee802.org/3/ba/public/jul08/agenda_01_0708.pdf
100GbE the 10-100m length must now be
covered by fiber. This can be done in the most cost-effective way by
OM3 fiber and 850nm lasers used for 10GbE for 100-300m applications and
streamlining them for this application. This is implicit in the
objective. The full capability of 10GbE 850nm VCSELS and OM3 fiber is
needed for most if not all of this length range at 100GbE, since they
designed for 300m in 802.3ae, and cost reduction opportunities exist.
portion of the 100-300m range covered
by OM3 fiber in 10GbE will still be needed for 100GbE applications in
centers. Fiber suppliers such as Corning
are aware of the market demand in this area (as are other suppliers)
presentations have been documenting the use of longer lengths in data
centers. http://www.ieee802.org/3/ba/public/AdHoc/MMF-Reach/swanson_xr_01_0608.pdf . The OM3 MM solution is the
effective way to address the 100-200m range. A target distance of 150m
½ of the 300m 10GbE capability and can easily be accommodated. However,
best done with a separate objective allowing the short length MM to be
down to absolutely minimize cost.
the distribution of lengths in data
centers and high performance computing environments, it is a fact many
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
for the longer lengths currently supplied. This mistake is an artifact
how the data is being presented.
absolutely contrary to the interests
of the end users for 802.3ba to neglect the 100-150m length segment
simple low-cost OM3 MM solution.
customers wanting TP links further
than 100 meters, I thought we pointed them to ISO 11801 and TIA568B
recommend fiber :)) for such runs.
Sent: Tuesday, August
Subject: Re: [802.3BA]
ad hoc next step concern
At 06:35 PM 8/25/2008 , Swanson, Steven E
we tell our customers who have
link lengths longer than 100m and want (or require) a standardized
We should tell them the same thing that we tell our twisted pair
That would be that their market is not large enough to:
- Warrant a separate solution in the standard.
- Burden the 100 meter solution with the extra costs required to meet
There is nothing terrible or onorous about this. A line has to be drawn
volume products. For passenger automobiles, the standard is clearly 5
passengers. Does a car salesman have to make excuses that the bulk of
product line only has a 5 passenger capacity? Of course not. Do some
companies think they can make money with larger vehicles? Of course.