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RE: 3PMD Proposal is not enough




George,
Thank you for giving us your perspective as a user of cabling systems. We at
Lucent who support the enterprise structured cabling business agree with
both your decisions and wishes. We have recommended for years and continue
to recommend the installation of both MM and SM fiber between buildings.
This recommendation is based on providing our customers the lowest-cost
total system solution over the life of the cabling infrastructure. Initially
installing both media results in the lowest cost because upgrading campus
cabling can be expensive (placing cable thru parking lots, roads, side-walks
and crossing other utilities like water, gas, electricity). The cost of
retrofitting in the future far out weighs the extra cable cost in most
cases, even if it goes unused for several years. Having both media allows
for use of the most cost effective electronics and/or available
technologies, be they MM or SM. 

Upgrades to in-building backbones are usually much easier than to campuses.
In fact, the building backbone subsystem is usually the easiest of all
subsystems to upgrade. In this case it often makes the most sense to upgrade
as needed to enable the lowest cost technology. This way, your cabling
investment does not go unused for significant lengths of time. 

One of our guiding philosophies in designing the new MMF was to keep the
solution simple. Hence we specify the fiber with sufficient performance to
support the simplest 10G opto-electronics technology (i.e. serial
transmission) and also eliminate mode conditioning patch cords, all while
retaining the support for legacy systems. This leads to the lowest operating
cost for the user as it provides a single-media solution for legacy systems
thru 10G. By adding WDM technology, the new multimode fiber can support
longer link lengths or higher bit rates. 

Regards,
Paul Kolesar
Lucent Technologies

	----------
	From:  Sullivan, George [SMTP:SULLIGE@mail.northgrum.com]
	Sent:  Monday, June 26, 2000 10:25 AM
	To:  'George, John Emanuel (John)'; 'Jonathan Thatcher';
'stds-802-3-hssg@ieee.org'
	Subject:  RE: 3PMD Proposal is not enough


	John and Group,
	As a "customer" we anticipated higher bandwidth requirements than
our
	multimode fiber could support.  So we installed hybrid cables
consisting of
	BOTH multi AND single mode fiber.  We want the least expensive
solution for
	our intra-building campus networks (up to 3.5 km fiber distance).
We don't
	care if its SM or MM fiber,  we DON'T want kludgy adapter launch
cables, we
	DON'T want another connector war, we DO want inexpensive, physically
small
	duplex connectors, we'd prefer a single lambda solution over WDM, we
believe
	in KISS.
	George Sullivan
	Senior Member, IEEE
	Senior Network Architect, Northrop Grumman