I was wondering how long this would take to make the list.  I just sent an
email about this to a colleague, so I happen to have an opinion at the
ready.

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There are two reasons I don't expect this to be a problem.  First is
business models.  Nobody chooses their university because of the Wi-Fi
performance, but people choose their wireless service provider (WSP) based
on network performance.  As such, network performance is likely more
important to WSPs than it is to us.  Interference is inherently mutual, so
WSP's don't want to be in the same band with us any more than we want to
be in the same band with them.  Second, is path loss.  5GHz signal
attenuates quickly in free space, and even more quickly through heavy
obstacles, such as exterior walls of buildings.

If you consider these two factors, then WSP's can't make wide use of LTE-U
for pervasive coverage because it's not cost effective, and they can't use
it in close proximity to Wi-Fi because it's unreliable.  Why then are they
expanding in this direction?  For use in small cells to cover a
high-density areas that the macro network has trouble serving.  Right now,
small cells can be a challenge to deploy where there is already a dense
macro network, because they have to use the same licensed bands for both
technologies.  If all available carriers in an area are already used, it's
difficult to add capacity because of increased interference.  Using
unlicensed spectrum avoids these problem.  Also, the areas where they
typically install these small cells don't often have strong Wi-Fi
coverage, and if they do, only one or two of the many available channels
are utilized.  This, combined with the high path loss between the outdoor
coverage area and nearby indoor coverage means there will usually be some
fairly clean channels to use for these small cells.

If we ever choose to provide pervasive outdoor Wi-Fi coverage, this could
be an issue, but I suspect we'll never do that.  Almost everybody has a
data plan, and outdoor LTE coverage is pretty good and improving all the
time.  We should provide Wi-Fi for indoor use, and let people use the cell
network outside.  We would do much better to provide site-licensed VPN
software for smart phones and tablets at $100K annually rather than $5M
per year to provide outdoor Wi-Fi that stops at the edge of campus.  If
things play out this way, using 5GHz for LTE instead of Wi-Fi would be to
everybody's advantage.  One reason Wi-Fi doesn't work optimally is because
much end user equipment (EUE) behaves badly and we attempt to accommodate
all EUE.  The WSP's can make far better use of the spectrum because they
only allow EUE that's built to their specifications.
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Let the debate begin!

Chuck Enfield
Manager, Wireless Systems & Engineering
Telecommunications & Networking Services
The Pennsylvania State University
110H, USB2, UP, PA 16802
ph: 814.863.8715
fx: 814.865.3988

-----Original Message-----
From: The EDUCAUSE Wireless Issues Constituent Group Listserv
[mailto:[email protected]] On Behalf Of Trent Hurt
Sent: Thursday, February 26, 2015 8:15 PM
To: [email protected]
Subject: [WIRELESS-LAN] LTE can mooch off of Wi-Fi spectrum with new
Qualcomm chipset | PCWorld

http://www.pcworld.com/article/2889792/lte-can-mooch-off-of-wifi-spectrum-
with-new-qualcomm-chipset.html

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