Wednesday, January 18, 2012

Wifi and the Internet of Things

Today is a day for thinking about the future of the web.  By virtue of being the author of this blog, that gets back to the future of communications infrastructure, and especially wifi.  Apologies in advance if I wax poetic, Wikipedia, Craigslist, and Reddit are all down today in protest of SOPA/PIPA. 

In recent years there's been a lot of chatter about the nature of technological convergence and the future of global telecommunications infrastructure.  Technological optimists, particularly those interested in the developing world trumpet, "mobile, mobile, mobile" and, on many levels, they're right... While we won't be ditching big screens and real keyboards any time soon, all statistics point to the fact that mobile devices account for an increasing number of transactions, tasks, and  amount of user online time.  Without doubt, mobile has been disruptive in the west, speeding the transition to cloud computing; a game-changer for Africa, bringing millions online; and largely responsible for an global wave of grassroots protest movements.  The thing that people tend to miss, however, when talking about the future dominance of mobile is that the device and the communications infrastructure are not one in the same.  

Our lust for data is killing mobile providers (you need only look as far as the near-extinction of the unlimited data plan), and it's technologically challenging to shrink mobile cell sizes enough to [economically] support traffic loads on limited spectrum licenses.  Mobile carriers depend on the extremely efficient use of spectrum that comes with careful site planning and modeling.  This gets exceedingly hard to do as cell sites become more numerous and demand cheaper installations.  

The licensed nature of mobile spectrum/devices also makes the sort of grassroots innovation and entrepreneurship that typifies the online world very difficult.  If we were only talking about making smartphones maybe we wouldn't care, but the smartphone is only the tip of the iceberg for the growing world of ubiquitous, cloud-enabled computing.

The ability to be "connected" at all times is clearly desirable (even if we choose to unplug sometimes for our own sanity).  Smartphones have achieved a permanent position in our pants pockets formerly afforded only to wallets and house keys; but connectedness is only useful to the degree that we can interact with our world through being connected.  Social was easy:  "I'm connected. You're connected, let's share some photos and poke each other", but what about STUFF?  

The natural next step for a connected person is to have a connected world to interact with.  We've already started with the big ones: Thermostats, security systems, home theater.  But the possibilities are endless, and it seems that the consumers are hungry.  If you think I'm kidding, check out this Kickstarter project from some of my former Media Lab colleagues that garnered a half a million bucks to create a wifi-enabled rubber(?) brick, with a temperature sensor and accelerometer, that can be used for useful stuff like telling you when your laundry is done.  Innovation to fill this new space of connected "stuff" will only thrive with the low entry barriers of an open internet, unlicensed spectrum and cheap hardware.  

In any case, the monolithic model of wireless communication is just not going to work.  A natural consequence of having EVERYTHING connected is a whole lot of unplanned and uncoordinated wireless communications generated by cheap, duty-cycled devices, flying around all over the place. This is the sort of thing that breaks traditional mobile communications. 

Wifi, especially with 802.11n and soon 802.11ac boasts so much capacity that even in an environment where 40 or more uncoordinated access points are all visible to each other (such as my bedroom), you can still expect to share 15Mbps or more with all the devices in your home, while your neighbor can do the same, simultaneously.  The limitations of wifi, in terms of range and penetration of obstacles, are strengths in the world where everything is a transmitter.  You won't send 15Mbps simultaneously to every home in my neighborhood with 4G...

As opposed to falling off in popularity as mobile improves, wifi has continued to strengthen.  Wifi will ultimately bridge the gap between wireline and mobile providers.  Cable companies have already embraced wifi as a way to increase the value of their services.  In Europe, mobile providers like T-Mobile have embraced wifi for years, and US mobile providers are now being forced to add wifi to offload traffic.  Ubiquitous, cheap, unlicensed.  It's a recipe for innovation, and a guarantee that wifi will only increase in importance as we become increasingly connected.  Keep hacking...


Tuesday, January 17, 2012

Development Kits Live!

Thanks to Nathan from California, the first Fabfi development kit went out the door today.  With the Monday holiday, I had the chance to do a little fit testing of the hardware on a spare pole I had lying around.  The itelite enclosure with integrated 18dBi dual-polarization patch took some modifications to mount the RouterStation, but was very robust and had a solid rubber gasket and grooved interface around the edges to keep water out.  The built-in ethernet extension plug was also a nice touch.  19" pigtails for the external antennas exit through an optional port on the itelite enclosure and screw directly into the 2.4Ghz antennas.





Below is a sample look at the current kit spec all mounted up.  Mounting with the top of the pole above the tops of the antennas is a common trick to protect against lightning strikes (20cm is usually enough):


I'd prefer to see the stock antenna mounts getting the antennas farther from the pole for decreased RF shadow and better spatial diversity, but this could be easily remedied with a crossbar. For applications requiring less 5Ghz gain, a clean option might be to offer a 6-way radome.  I might get a chance to test this out in the near future.