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RE: Going the distance




In Jonathan's notes, he mentions support media from ISO/IEC 11801. Wouldn't
this cover both the installed base and any new media accepted by ISO/IEC
11801. If so, I would see no reason to include the wording "installed base"
in our distance objective. Brian would you agree with this? 

Ed-Lucent

> ----------
> From: 	Jonathan Thatcher[SMTP:jonathan@picolight.com]
> Sent: 	Wednesday, June 30, 1999 11:08 PM
> To: 	HSSG
> Subject: 	RE: Going the distance
> 
> 
> Just to make sure that everyone is keeping everything in perspective. The
> tabled motion on distance that we will pick up in Montreal currently
> reads:
> 
> Adopt as objectives for the Higher Speed Study Group:
> 
> Provide a family of Physical Layer specifications which support a link
> distance of:
> a. At least 100 m on multimode fiber
> b. At least 3 km on single mode fiber
> 
> Move: Bob Grow
> Second: Tom Dineen
> 
> Rich Taborek, with Howard Frazier seconding, is proposing the following as
> an amendment/replacement:
> 
> That the distance objective support the premises cabling plant distances
> as
> specified in ISO/IEC 11801
> 
>       The distances supported in ISO/IEC 11801 are:
> 
>       100 m for horizontal cabling
>       550 m for vertical cabling
>       2-3 km for campus cabling
> 
> Compare these to the 802.3z (Nov 96) objectives:
> 
> 11. Provide a family of Physical Layer specifications which support a link
> distance of:
> 
> a. At least 25 m on copper (100 m preferred)
> 
> b. At least 500 on multimode fiber
> 
> c. At least 3 km on single mode fiber
> 
> and 
> 
> 
> 13. Support media selected from ISO/ IEC 11801
> 
> For those of you that weren't there for 802.3z, the gigabit standard met
> and
> supports this last set of objectives! It wasn't particularly easy at times
> (in fact, for those of us who lived through it, we quip and wonder why we
> would ever want to do this again). In fact, had it not been for these
> objectives, we might have -- no, we probably would have -- given up and
> resolved on a much shorter set of distances. Howard Frazier, armed with
> this
> set of objectives, somehow managed to keep us going until we got it done.
> I
> do not think I am over stating this!
> 
> Everyone, please think long and hard about the implications of these
> objectives on the future work of the HSSG. There are any number of
> significant differences in these three sets. I will note only one: item
> "b"
> of the original motion (same as the 802.3z objective 11c) meets all the
> requirements of the amendment to it. 
> 
> Having worked in a number of standards activities, I have come to
> appreciate
> the value of setting the objectives early in the process. These become a
> guide, a challenge, and a metric by which much of the work is gauged. If
> there is any ambiguity as to the intent of the objectives, we will be
> doing
> nothing but postponing the difficult decisions. If ambiguity is the only
> way
> we can achieve consensus, I am not optimistic we will succeed. This is a
> difficult thing to do. It is worth doing right. Whatever the process we
> use,
> let's make sure the end result is something that everyone can get behind.
> 
> jonathan
> 
> > -----Original Message-----
> > .... deleted ....
>