IEEE Electrification Magazine - June 2018 - 36

Features and Functionality
Range (Coverage)1
Performance Reliability
Scalability
Data Rate
Speed
Latency
Two Way
Over-the-Air Upgrades
Types of
Peer to Peer
Communication
Voice
Mobility

xx
reliability
xx
upgradability
xx
security
xx
scalability
xx
data management
xx
return on investment (RoI) and

financial sustainability.

Network Architecture
Wi-SUN

The Wi-sUn is a mesh-based technology (Figure 2), built in conformance to the
Ieee 802.15.4g specification. It is backed
Ease of Use
by the Wi-sUn Alliance, a global
industry alliance that promotes the
Communications Module Energy Use
Spectrum
Other
Wi-sUn specification. Wi-sUn leverSecurity
ages third-party labs and test facili1Assumes obstructed or semiobstructed real-world environments, not a free space.
ties to develop and execute trials
certifying that Ieee 802.15.4g-based
Figure 1. An overview and technology comparison of the Wi-SUN, NB-IoT, and LoRa. Wi-SUN: wireIoT equipment conforms to the stanless smart ubiquitous network; NB-IoT: narrowband IoT; LoRa: long range; API: application prodard and interoperates with other
gramming interface.
certified equipment. Wi-sUns support star and mesh topologies as well
use cases mature. The bottom line is this: choose a flexible
as hybrid star/mesh deployments, but they are typically laid
network architecture that can incorporate multiple transout in a mesh topology where each node relays data for the
ports and technologies, not just a wireless smart ubiquinetwork to provide connectivity. Furthermore, Wi-sUns can
tous network (Wi-sUn), cellular carrier, bluetooth low
connect both powered and battery-operated devices.
energy, or long range (loRa) but all of these combined into
Narrowband-IoT
a single cohesive architecture. (see Figure 1 for an overThe narrowband-IoT (nB-IoT) is a mobile technology specview of a few different types of architectures.)
ification by the 3rd generation Partnership Project stanNetwork Requirements
dards body that is expected to be used for low power and
If there is anything that existing smart city deployments
infrequently transmitting devices. The nB-IoT can operate
have proven to date, it's that the technology they put in
in the global system for Mobile communications specplace must be standards based, cost effective, and reliable.
trum or utilize an unused resource block within a longThe goal is to always future-proof any deployment. That's
term evolution carrier's guard band. nB-IoT-compliant
a laudatory goal for cities to pursue so that unforeseeable
chip sets are now becoming available, while network
changes in network demands can be managed, ensuring
topologies are star based (Figure 3). The cellular carriers
that the benefits from new applications can be realized.
manage their own certification programs.
IoT networks must demonstrate specific characteristics
There are some challenges that come with the nB-IoT
across eight key areas:
because it is a cellular technology. A lack of spectrum conxx
architecture
sistency, limited geographic coverage, low throughput, and
xx
standards
limited battery life make it less compelling for IoT use
Communications Module Hardware
Firmware
APIs and Data Access

Figure 2. An example of a mesh-based architecture.

I EEE E l e c t r i f i c a t i on M a gaz ine / J UN E 2018

Figure 3. An example of a star-based architecture, on which
LoRaWANs and NB-IoT networks are based.

Table of Contents for the Digital Edition of IEEE Electrification Magazine - June 2018