NEXT GENERATION COMMS IOT DEPLOYMENTS
Which network type or
protocol to use?
As with most projects, cost of delivery
for data is a primary concern that
must be addressed. LoRaWAN and
Sigfox are now at a level of maturity
where the devices are cost-effective.
Initially, cellular was a much higher
cost, but is now starting to achieve
cost-effectiveness. But in terms of
usage costs, for NB-IoT and LTE-M,
users are still paying for data usage
on the network (paying by the byte),
whereas LoRaWAN leverages the freeto
air spectrum facility and charges
are based on device licensing, and in
the case of Sigfox, per message.
Even though there appears to be
a clear differential in terms of cost
models, the choice of network and
protocol isn’t straightforward. As IoT
rollouts become more commonplace,
there are elements within a LoRaWAN
environment that create cause
for concern. With multiple devices
sharing the LoRaWAN spectrum
there can be potential collisions on
the network and lost messages.
In order to ensure each message
arrives, the LoRaWAN protocol and
software controlling the network has
been adapted further to mitigate
against this happening by spreading
messages across multiple channels,
monitoring message counters, and
other techniques.
Identifying the parameters of
the use case and the nature of the
deployment is very important. If a
message with telemetry data only
needs to be sent when there is a
status change, this won’t necessarily
create network congestion on a
LoRaWAN Network. Regular 15
minute monitoring from multiple
sensors in an area may however
require additional gateway capacity
to ensure spreading the sensor
message load. But if your use case
requires guaranteed delivery of trafc
within a specic time period, or a
constant stream of messages cellular
protocols such as NB-IoT and LTE-M
may need to be used.
Use cases
Another consideration is the protocols
certain sectors are already using
to gain traction. There’s been a
tremendous uptake and interest in
LoRaWAN among local government that
see it as a mechanism they can use to
scale multiple use cases at once.
In the utility monitoring sector,
NB-IoT appears to be the protocol
gaining the advantage. No gateways
are required as signal towers are
the enablement point and it has
deep penetration under the ground
with good signal strength to reach
its destination. But when it comes
to monitoring elements deep
within buildings, LoRaWAN can be
more effective compared to what
NB-IoT can do from the outside
in. Refrigeration and temperature
monitoring is one such example and
LoRaWAN can provide an effective
protocol in this instance, measuring
the temperature deep inside the
building, all the way down to the
probe where intensive monitoring and
data collection is critical.
For a use case such as measuring
readings intermittently, on an alert
basis or once an hour, you need
to conserve battery power so the
sensors last a long time and will likely
be leading towards the unlicensed
spectrum. Whereas within a healthcare
monitoring scenario, such as in
someone’s home or in an ambulance
on the move, readings will need to be
sent through immediately, so will need
to rely on the licensed spectrum, such
as LTE-M.
Blended connectivity
Currently, there is no one protocol
that is optimised for every use
case or can cover an entire estate.
The solution is to deploy a hybrid
model, one which blends different
connectivity protocols together,
from the unlicensed and licenced
spectrums, to achieve total estate
and use case coverage. A blended
approach is inherently exible, costeffective
and scalable for those
looking to reap the benets of
mass-scale IoT but uncertain as to
how and where to proceed.
Longevity is crucial for the
success of an IoT deployment. No
business wants to rip and replace
the technology after ten years. It’s
clear that LoRaWAN in particular
is on a growth trajectory that will
provide that longevity. And the
eventual maturity of 5G will also
become another option for IoT
projects, with much more efciency
in terms of capability to connect
millions of sensors. 5G may be a
way off yet, but it’s likely that many
estates of devices and networks
will eventually have parts of them
consumed by 5G.
With a blended model of different
protocols covering each estate, to
make it efcient and streamlined,
it’s important for a single platform
to be used that can bring it all
together and be received, read
and analysed in one place. NBIoT,
LoRaWAN, LTE-M, Sigfox are
all becoming industry-standard
protocols that are each received
in a different format. But they can
be streamlined into one hub that
intercepts the trafc and converts
it into a protocol that the receiving
application requires. By working with
a partner offering all types of IoT
connectivity in a blended solution,
projects can be rolled out in the
condence that each protocol has
been considered and is supported,
to maximise the functionality,
practicality and cost-efciency of an
entire IoT project.
26 9 March 2021 www.newelectronics.co.uk
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