IEEE 40GE & 100GE

Justin M. Streiner streiner at
Wed Dec 12 12:50:48 UTC 2007

On Wed, 12 Dec 2007, 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 here.

I'm not in any of the Equinix facilities, but I do run a decent-sized 
urban campus network and a 3km-4km distance limitation would be cutting it 
really close for me in some cases.  Some of the 10G links on my backbone 
today do require multiple physical cross-connects, which would eats into 
the link budget.  Most of my backbone connections work find with 10G-LX4 
optics, but there are a few places where 10G-ER is needed.

I haven't read the draft spec yet to see what's being proposed for a link 
budget at 3/4/10km, but that's just as important as the physical distance.


> 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 directly
>> (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 number
>> of 100GE end users that >90% of their data center and short interconnect
>> needs would be met by a reach objective less then 4km (versus 10km.)
>> With such a reach distribution, a 4km or less optimized reach objective
>> would result in overall cost savings.
>> As part of the HSSG effort to review this proposal, numerous requests,
>> 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 reach
>> 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 12/7
>> Reach Ad Hoc conference call minutes.
>> I would encourage any HSSG participant that views their volume 100GE SMF
>> 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 on
>> the IEEE website
>> Thank you for your contributions
>> Andy
>> ----------

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