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E. Fraccaroli and D. Quaglia
device is not attached to a specific base station unlike Bluetooth, IEEE 802.15.4,
Wi-Fi, or cellular protocols. The broadcast message is received by any base station
in the range (three in average, according to Sigfox). The spatial distribution of
base stations, where the same signal can be received under different conditions,
together with message repetition on different frequencies, contributes to increase
reliability considering that unlicensed bands are very crowded. The uplink messages
are 26 bytes long with a 12 bytes data payload. Therefore they take a maximum of
2 s to be transmitted over the air. The payload allowance in downlink messages is
8 bytes. Sigfox technology was mainly conceived for upload operations and the
fact that listening intervals are very limited increases security. Security is mainly
enforced in the core Sigfox network, among base stations and towards the cloud.
Low bit rate and simple radio modulation enable a 163.3 dB link budget for longrange communications. Sigfox nodes are designed to transmit less than 1 min per
day. This feature together with the absence of a tight connection with the base station
leads to low transmission and computation overhead to maximize the autonomy of
devices.
3.3.11 Z-Wave
Z-Wave is a wireless communications standard used primarily for home automation [45]. It features a mesh network using low-energy radio waves to communicate
from appliance to appliance, allowing for wireless control of domestic appliances
and other devices, such as lighting control, security systems, thermostats, windows,
locks, and door openers. Like other protocols and systems aimed at the home and
office automation market, a Z-Wave system can be controlled via the Internet from
a smartphone, tablet, or computer and locally through a smart speaker, wireless key
fob, or wall-mounted panel with a Z-Wave gateway or central control device serving
as both the hub controller and portal to the outside. Z-Wave provides Application
Layer interoperability between home control systems of different manufacturers that
are a part of its alliance. Z-Wave Plus is the latest certification standard that enforces
security and automatic configuration. Z-Wave classic is also fully interoperable but
may require more configuration effort.
Z-Wave is a proprietary standard which operates in sub-GHz radio-frequency
bands, at 868.42 MHz in Europe and 908.42 MHz in the United States. Z-Wave
employs the Frequency Shift Keying (FSK) and the Gaussian Frequency Shift
Keying (GFSK) modulations. While Z-Wave has a range of 100 m in open air,
building materials reduce that range, and therefore it is recommended to have a
Z-Wave device roughly every 10 m, or closer for maximum efficiency. Physical
bitrate ranges from 40 to 100 kb/s. Z-Wave is based on a mesh network topology.
This means each (non-battery) device installed in the network can become a signal
repeater. Each Z-Wave network can support up to 232 devices.
E. Fraccaroli and D. Quaglia
device is not attached to a specific base station unlike Bluetooth, IEEE 802.15.4,
Wi-Fi, or cellular protocols. The broadcast message is received by any base station
in the range (three in average, according to Sigfox). The spatial distribution of
base stations, where the same signal can be received under different conditions,
together with message repetition on different frequencies, contributes to increase
reliability considering that unlicensed bands are very crowded. The uplink messages
are 26 bytes long with a 12 bytes data payload. Therefore they take a maximum of
2 s to be transmitted over the air. The payload allowance in downlink messages is
8 bytes. Sigfox technology was mainly conceived for upload operations and the
fact that listening intervals are very limited increases security. Security is mainly
enforced in the core Sigfox network, among base stations and towards the cloud.
Low bit rate and simple radio modulation enable a 163.3 dB link budget for longrange communications. Sigfox nodes are designed to transmit less than 1 min per
day. This feature together with the absence of a tight connection with the base station
leads to low transmission and computation overhead to maximize the autonomy of
devices.
3.3.11 Z-Wave
Z-Wave is a wireless communications standard used primarily for home automation [45]. It features a mesh network using low-energy radio waves to communicate
from appliance to appliance, allowing for wireless control of domestic appliances
and other devices, such as lighting control, security systems, thermostats, windows,
locks, and door openers. Like other protocols and systems aimed at the home and
office automation market, a Z-Wave system can be controlled via the Internet from
a smartphone, tablet, or computer and locally through a smart speaker, wireless key
fob, or wall-mounted panel with a Z-Wave gateway or central control device serving
as both the hub controller and portal to the outside. Z-Wave provides Application
Layer interoperability between home control systems of different manufacturers that
are a part of its alliance. Z-Wave Plus is the latest certification standard that enforces
security and automatic configuration. Z-Wave classic is also fully interoperable but
may require more configuration effort.
Z-Wave is a proprietary standard which operates in sub-GHz radio-frequency
bands, at 868.42 MHz in Europe and 908.42 MHz in the United States. Z-Wave
employs the Frequency Shift Keying (FSK) and the Gaussian Frequency Shift
Keying (GFSK) modulations. While Z-Wave has a range of 100 m in open air,
building materials reduce that range, and therefore it is recommended to have a
Z-Wave device roughly every 10 m, or closer for maximum efficiency. Physical
bitrate ranges from 40 to 100 kb/s. Z-Wave is based on a mesh network topology.
This means each (non-battery) device installed in the network can become a signal
repeater. Each Z-Wave network can support up to 232 devices.