60 February 2016
protocol. With multiple standards and
protocols in use, this is a problem. In
addition, even if the same standards
and protocols are used, minor
variations can keep devices from
working together. This will require
rigid testing and certification to
Ease of installation is a huge
issue — at least for the consumer.
If installation and setup processes
are complex, arcane, and lengthy,
consumers will just be frustrated and
home Io T could be a flop — all the
more reason to take the extra design
time to make sure installation is a
Io T systems are designed to
capture data. This they do well. They
can collect a massive amount of data
is a short time. This means having
enough memory to store the data.
Then, what do you do will all that
data? Do you display it, analyze it,
or what? Some early studies of Io T
indicate that 70 to 90 percent of
all the data collected is never used.
(That kind of statistic kind of makes
you wonder why the application was
implemented in the first place.) This is
a major issue to think through before
investing in Io T.
Multiple standards is a key
issue as indicated earlier. Wireless
standards are a good example.
There are many short range wireless
technologies that will work with Io T.
All are vying for a piece of the Io T
pie. Wi-Fi is probably one of the
early leaders in this race. It is highly
developed with multiple variations,
plus an in-place certification process.
Most homes have a Wi-Fi router
already in use. These days, virtually
all laptops, tablets, and smartphones
include Wi-Fi. It is a good reliable
choice and an early leader in the
standards battle. Wi-Fi is fast and
convenient, but can be expensive
overkill for many simple sensor
Bluetooth is another good choice.
It is widely available in smartphones,
and the new low energy version will
ensure that sensors can run for years
on a single battery. Certification is
available to make sure all devices
ZigBee is another standard that is
a major contender — especially where
lots of sensors are involved. Based
on the IEEE 802.15.4 standard (see
sidebar), ZigBee’s mesh topology lets
you build systems with hundreds or
even thousands of sensors. It’s a great
choice for business and industry.
Yet another standard showing up
in smart home products is Z-Wave.
This is a simple wireless technology
that is ideal for low data rate home
monitoring and control. It is low cost
Of course, there are many
others to look at. There is Weightless
that uses the white spaces on
vacated VHF and UHF TV bands.
LoRa is another that uses the lower
frequencies below 1 GHz. Both
Weightless and LoRa promise longer
range connectivity up to several miles
in applications where the devices are
some distance away.
Cellular connectivity is also an
option. There are cell phone chips
and modules, and most wireless
carriers offer connection services.
This is a good reliable choice for more
Let’s not forget the software side
of Io T. There are multiple different
software protocols for handling the
data. These operate with the wireless
chips and modules. Some examples
are MQTT, JSON, IPSO, Io Tivity,
AllJoyn, and Apple’s HomeKit. A
popular standard is 6Lo WPAN that
lets other protocols use the IPv6
A more recent example is
Thread. Thread uses the popular IEEE
802.15.4 wireless standard, but adds
a mesh topology protocol to handle
many sensors or other devices.
Been There, Done That
The idea of Io T is not new. It
has been around for decades. We
used to call it remote monitoring
and control telemetry. To me,
Io T is just telemetry on a grander
scale, thanks to the Internet
and lots of low cost/low power
Now that it’s easier than ever
to create products we can operate
remotely or collect data from,
I suspect Io T will become even
more successful and prolific.
Although, personally, I’d be
okay with us bringing back X10
power line controllers and the
THE LATEST IN NETWORKING AND WIRELESS TECHNOLOGIES
What is 802.15.4?
802.15.4 is one of the Institute of Electrical and Electronic Engineers’
(IEEE) short range wireless standards. It works in several of the
unlicensed spectrum, but primarily in the 2. 4 to 24.835 GHz spectrum
where Wi-Fi and Bluetooth reside. It uses direct sequence spread
spectrum (DSSS) with differential BPSK or offset QPSK modulation.
Data rates can be up to 250 kb/s. The typical power output is 1
mW or 0 dBm. The range is up to 10 meters or so, depending on the
environment. It uses very low power, so can operate from a battery for
years. This standard implements the physical (PHY) and media access
control (MAC) layers of the OSI networking model. Other networking
layers are built on this, based on the application.
This is a popular model as other standards are based on it, including
ZigBee, ISA 100-11a, WirelessHART, and Thread.