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RE: [EFM][EFM-P2P] 100Mbps P2P over SMF

Hi Ulf, I would be interested in 100M, particularly in the context of the
local legs of active architectures and the HALF-PON architecture I brought
up a while back ( ).
It has some similarities to your recent presentation at:

We will run into the same multiple-distance-support questions as 1G P2P.
100M seems most interesting to me--in the context of an active
architecture--with a long distribution fiber at 1G, and short feeders on the
local legs to each ONU at 100M (or, 1G broadcast-and-select passive
downstream, and 100M upstream to an active node for HALF-PON). How short is
short, is the question. Maybe 300m; maybe 500m; maybe 1-2km. Inexpensive is
key. The INTENT should be to serve short feeders in this range, rather than
trying to be all things to all people. The distance extension premium may be
too high to justify the cost per user of the longer distance capability as
an umbrella solution. 
If the network layout needs longer multi-km feeders, a different
architecture (or proprietary distance-extended 100M) would be used. 300m
serves a high percentage of medium- to high-density residential applications
at 16:1 aggregation. Possibly (haven't run any numbers on this) 64:1 fits
with 1km. If the cost to increase from 300m to 1km is only a few bucks per
user, then it makes sense for 1km to be the goal. If it costs, say, 30 bucks
to go from 300m to 1-2km capability, it will be hard to justify anything but
2 separate specs. 30 bucks times zillions of users is a lot of Cap-ex that
goes wasted for a network operator whose layout logistics dictate deployment
at 16:1 / 300m, but has to pay the premium for the capabilities to reach 1km
because the spec says so. Compare the costs of 100BaseSX versus 100BaseFX,
for example (which is much greater than 30 bucks).

However, these are all points that would be addressed, and no doubt
resolved, AFTER the general concept of 100Mbps P2P is approved. I am in
favor of the general concept, and believe it meets the 5 criteria using the
same arguments as the current set of P2P and P2MP. Architecturally, active
topologies were left out of EFM for some reason. They are a natural
complement to the current set of supported architectures, and should be

--Dave Horne

-----Original Message-----
From: Ulf Jönsson F (ERA) [mailto:Ulf.F.Jonsson@xxxxxxxxxxxxxxx]
Sent: Tuesday, November 20, 2001 5:54 AM
Subject: [EFM][EFM-P2P] 100Mbps P2P over SMF

Hi all,

On the January meeting we will make a presentation on the 5 criteria for
100Mbps P2P over SMF. Many of you have already indicated your interest and
in order to have a broad acceptance of the proposal we invite all of you who
would like to support, contribute or participate in this presentation. 

Please respond to me if you are interested. We intend to have a first draft
presentation during next week that we can discuss off-line. 

Best regards,

Ulf Jönsson
+46 70 2673313