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RE: [EFM] Moving forward on extended temperature range optics

Bruce, Brian and Richard,

I'd like to point out where this chain of thought goes wrong, especially as the logical disconnects have been repeated later in the thread.  See below:

> -----Original Message-----
> From: Bruce Tolley [mailto:btolley@xxxxxxxxx]
> Sent: 16 January 2003 19:59
> To:;
> Subject: [EFM] Moving forward on extended temperature range optics
> Piers and all
> I gave my self the action to help move forward the outstanding issue 
> regarding extended temperature ranges for P2P and P2MP optics
> We have an objective to include in our specification of PHYs, 
> support for 
> extended temperature range optics

Yes.  Support, not mandatory requirement.
> The task force has in the past passed motions to specify EFM 
> optics at -40 
> to +85 C

To specify the optics, not the temperature.  This is very clear from the January and March 2002 motions.  See e.g. the March Joiner motion "The basis for the first draft of the 802.3ah 1000Base-LX extended temperature objective be met with text that uses 1000Base-LX 5 km single mode specification (clause 38) as the starting point with the following changes and additions:
- Informative temperature range -40-+ 85 deg C


January Motion #11
Motion: to create informative annex to address environmental considerations.
Mover: Chris DiMinico
Second: Alan Flatman 
> Network operators have on multiple occasions communicated the 
> requirement 
> for extended temperature solutions.

This is where the logic really falls apart.

First, is it not just a small subset of network operators (US ones) who aren't installing much FTTB.  Other network operators may have different physical strategies, climates, and requirements.

Second, network operators need many things; working capital, fire safety, an electricity supply...  It does not follow that 802.3 is bound to provide any of them.  Environmental requirements such as these are out of scope of this standard - that's why temperature is to be addressed in an informative annex.

Of course, customers will impose environmental requirements in their procurement specs - and Telcordia specs for example are effectively, procurement specs.

> As recently as the Vancouver meeting, several box vendors 
> (including me)b 
> communicated the requirement for extended temperature range 
> optics.

Same lack of connected logic.  Someone's need doesn't mean that 802.3 is bound to supply.  Temperature specs are available in the market from other sources, who have more expertise in the matter.


> We need 
> to agree on a path to move forward.
> So if interested parties want to forward to me their email 
> addresses, I 
> will host a conference call next week dedicated to this 
> issue. I think we 
> need to focus on a test specified in each PMD clause, to agree on the 
> ranges for OLT and ONU optics, to consider the possible 
> special case of 
> bidis that include 1550 nm DFBs, and to identify any PMD that 
> might only 
> need to be supported at standard, commercial temperatures.
> thanks
> Bruce Tolley
> Cisco Systems
>   At 04:11 PM 1/8/2003 +0100, piers_dawe@xxxxxxxxxxx wrote:
> >G.983.3 refers to ETS 300 019.  This is a very readable series of 
> >documents from the European Telecommunications Standards 
> Institute, giving 
> >a classification of environmental conditions, e.g. weatherprotected 
> >locations, non-weatherprotected, underground.  It uses four 
> classes of 
> >climatic conditions:
> >         "applies to most of Europe"
> >         extended
> >         extremely cold
> >         extremely warm dry
> >
> >And even better, up-to-date drafts are available on the web, e.g. at
> >
20101o.pdf .
>It is not the business of 802 to pick between these classes but we can 
>refer the readers of our standard to this information.
>ITU-T and ANSI T1 do not have similar documents.
>Both G.983.3 and refer to IEC 60721, classification of environmental 
>IEC 60721-3-4 - Ed. 2.0  Classification of environmental conditions - Part 
>3: Classification of groups of environmental parameters and their 
>severities - Section 4: Stationary use at non-weatherprotected 
>locations  1995-01 is available for CHF99 at 
> .

Bruce Tolley
Senior Manager, Emerging Technologies
Gigabit Systems Business Unit
Cisco Systems
170 West Tasman Drive
San Jose, CA 95134-1706
internet: btolley@xxxxxxxxx
ip phone: 408-526-4534