If such idea
for QSFP is foreseeable for
the sake of port density, donot you think it will be great to move XR
into an annex
of the draft? I suggest this should be re-visited during CC.
I feel the
resistance from the group for
the reason XR may potentially compete against others like 100m option,
it is just a complimentary.
With strong negative vote on the XR in Seoul
I thought this subject is in bed.
I was initially supporter of XR but in Seoul
I voted against it as we were not
converging to a solution and started to distract the group. I do agree
there is a small but important market for >100 m on OM3.
Applications requiring 101-300 m reach on OM3 still is possible using
compliant components and I would not be surprise to even see some of
component get packaged in QSFP as the 10G port density grows.
Abbott, John S Dr
and 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 link distance must and will
cost-effectively covered by MM fiber, but the 802.3ba objectives don’t
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 taking the OM3 fiber
850nm lasers used for 10GbE for 100-300m applications and streamlining
this application. This is implicit in the existing MM objective. The
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
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 data centers.
such as Corning are
the market demand in this area (as are other suppliers) and
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 most cost effective way to address
the 100-200m range. A target distance of 150m is ½ of the 300m 10GbE
capability and can easily be accommodated. However, it is best done
separate objective allowing the short length MM to be stripped down to
absolutely minimize cost.
the distribution of lengths in data centers and high
performance computing environments, it is a fact many of the short
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
lengths currently supplied. This mistake is an artifact of how the
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 wrote:
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.