IEEE 40GE & 100GE

Chris Cole chris.cole at
Fri Dec 14 22:37:59 UTC 2007

The 100G 40km reach (the 40G in your email I am assuming is a type) will
be a black/white code, and it will not support DWDM.


-----Original Message-----
From: Wayne E. Bouchard [mailto:web at] 
Sent: Friday, December 14, 2007 11:42 AM
To: Robert E. Seastrom
Cc: Bora Akyol; nanog at; Chris Cole
Subject: Re: IEEE 40GE & 100GE

I have three practical uses for 40G at present...

First and most obvious is router to router. In this case, if the
routers are in the same cage, there's little reason to want to be able
to push more than 100 feet. (The same applies to aggregation switches
and similar.)

The second use is links around a campus. Now we're pushing
distances. ESPECIALLY when you consider budgets due to patch losses
and so on. In this case, 3-4km is probably still adequate for me in
most cases. (Equinix's DC area will probably work with 3km as long as
they don't take it through 8 patch panels before they get to you. DC3
is the only one to be concerned about because of the added
inter-building distance.)

The third use for this is across a metro area. (Lets face it, it's
hard to find a good amount of space in any one location.) In this
case, in most areas, I have a need to use DWDM. I would still need to
do this on dark fiber since some locations can quite easily push more
than 40 gigs back to the core. So I either double my fiber costs and
buy two pair to each location or I use DWDM. So now the concern is
when my DWDM vendor will be able to mux these together. That, above
and beyond "how far can you push this?" If I've got a long run and no
place to put an amplifier in the middle, even 10km may mean I'm SOL.

So from my POV, I have a vested insterest in all three options and the
relevant orders of magnitude between each one. For the sake of
instroducing the technology, should it not persue the same path that
10GE did? That is, focus on the first condition with an eye to the
second and add the third once you've got the problems with the first
two worked out?

On Wed, Dec 12, 2007 at 06:27:55AM -0500, Robert E. Seastrom wrote:
> A practical question here: does anyone know offhand if 4km reach is
> adequate for interbuilding access (i.e., DC[124] to DC3) access at
> Equinix Ashburn, including worst-case interior wiring and cross
> connects?  I'm thinking that's cutting it close.  The enterprise
> people are substantially less likely to find themselves with a lot of
> interconnections in a GCE (Ginormous Campus Environment) than we are,
> and I suspect that skews the 90% number a bit.  Folks who are more
> familiar with the layout of other facilities may wish to chime in
>                                         ---Rob
> Bora Akyol <bora.akyol at> writes:
> > IEEE is seeking feedback from network operators etc on the reach
> > requirements for 40GE & 100GE.
> >
> > If you have direct feedback to give, please contact Chris Cole
> > (email address below).
> >
> > This is very important as it will directly impact how much you pay
for those
> > soon to be cherished 40 & 100 GE hardware in the future. I believe
> > information on how many patch panel connections you expect the links
to go
> > through is also highly valued.
> >
> > Regards
> >
> > Bora
> >
> >
> > From: Chris Cole <chris.cole at FINISAR.COM>
> > Subject: Re: [HSSG] Reach Ad Hoc
> > Date: Tue, 11 Dec 2007 16:21:31 -0800
> > Reply-To: Chris Cole <chris.cole at FINISAR.COM>
> >
> > During the November HSSG meeting, optics vendors made a presentation
> > proposing changing the 10km reach objective to 3km or 4km. One of my
> > motivations for working on the proposal was informal input from a
> > of 100GE end users that >90% of their data center and short
> > needs would be met by a reach objective less then 4km (versus 10km.)
> > With such a reach distribution, a 4km or less optimized reach
> > would result in overall cost savings.
> >
> > As part of the HSSG effort to review this proposal, numerous
> > both informal as well as from the HSSG chair and Reach Ad Hoc chair,
> > have been made for contributions to quantify the 10km and under
> > distribution. While the optics vendors as suppliers can accurately
> > represent the relative costs of optics alternatives, they can not
> > represent end user requirements.
> >
> > To date, we have seen no end user presentation or data supporting
> > changing the 10km reach objective to 4km or less. Unless such
> > contributions are forthcoming, it is likely that there will be no
> > motivation to make the change. This sentiment can be seen in the
> > Reach Ad Hoc conference call minutes.
> >
> > I would encourage any HSSG participant that views their volume 100GE
> > needs as better met by a 4km or shorter reach objective to make a
> > contribution containing reach distribution data in support of this
> > position. Otherwise we will move forward with the existing approved
> > objectives.
> >
> > Chris
> >
> > ________________________________________
> >
> > From: Andy Moorwood [mailto:amoorwood at EXTREMENETWORKS.COM]
> > Sent: Tuesday, December 11, 2007 6:03 AM
> > Subject: [HSSG] Reach Ad Hoc
> >
> > Colleagues, the meeting notes from our call last week are now posted
> > the IEEE website
> >
> > Thank you for your contributions
> > Andy
> >
> > ----------

Wayne Bouchard
web at
Network Dude

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