[Pc_Support] Re:Large area WiFi (City)] -- Rice TAPs, 420Mbps backhaul w/10Mbps access

[Bryan J. Smith]

At last week's IEEE 802.11s (Mesh Networking) sub-committee meeting, we
met up with (fellow C-USA member ;-) Rice University who is implementing
a rather interesting, Metropolitan-wide mesh networking under a grant
from the National Science Foundation (NSF) and, more recently, with
funding from Intel.

They are currently using five (5) back-haul "Transit Access Points
(TAPs)" to cover a little more than a dozen square miles of Houston.
The current TAP design just uses twelve (12) 2.4GHz, although they are
playing with 4.5/5GHz and other bands.  Although they They are _not_
standard 802.11a/b/g radios/channels, they are up to 40MHz "super-
channels" (much like what Motorola's Mesh does right now), which cuts
through standard 802.11a/b/g like butter (at least Motorola's Mesh does
for us).  The TAP logic is of a custom design, with Xilinx FPGAs with
PowerPC cores ($$$), with GbE PHYs, DACs, ADCs and other ICs -- the
Xilinx largely because they are still prototyping the final design.

But they are able to get roughly a 420Mbit backhaul in current testing
with just the 2.4GHz channels!

The embedded operating system is Linux, of course, and their research,
including the mesh logic, is _open_source_!

The access board is a dual-2.4/5GHz and is being fabbed now.  I assume
it's probably flexible in design to accommodate all sorts of non-
standard "super-channeling" and might not be final (let alone a bit
pricey until quantity/commodity).  The idea is the access board can give
anyone a 10Mbps burst pipe from anywhere within a few miles.  Rice has
not tested longer distances yet, largely because they are looking for
the "every 3 mile" density for typical user performance.

Just in case you're interested ...
  http://taps.rice.edu/  

A poster with an introduction to the design ...
  http://taps.rice.edu/taps-hw-poster.pdf  


-- 
Bryan J. Smith             Professional, technical annoyance
mailto:b.j.smith at ieee.org       http://thebs413.blogspot.com
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****** Speed doesn't kill.  Difference in speed does! ******