What Are the Major IoT Communication Protocols Used for Smart Buildings?

IoT communication protocols for smart buildings

The Internet of Things (IoT) is bringing convenience and increased efficiency to nearly every corner of modern life. IoT communication protocols for smart buildings are the key to making the most of these latest innovations. Smart buildings are taking advantage of new technologies in ways that offer significant benefits in terms of environmental impact and cost, but also by creating business value. For years, commercial properties have benefited from basic electronic automation systems. Now, IoT with integrated sensors, real-time communication, and advanced analytics can make an even more significant impact on costs and tenant satisfaction.

The key to successful IoT implementation is finding the proper communication protocol that allows devices to communicate seamlessly. The protocol is the “language” of the components of the system used to exchange data. If the devices cannot communicate or cannot communicate efficiently, the entire smart building risks running inefficiently or not running at all.

Due to the critical nature of these communication protocols for IoT, it is essential to understand the options. Below are the major IoT communication protocols for smart buildings. 


Standard: NB-IoT Cat-NB2

Channel Bandwidth: 180 kHz

Data Encryption: EPS-AKA

Frequencies: uses the same sub-6 GHz wireless spectrum as the 4G LTE technology

Range: Based on 4G Network Coverage

Data Rate (downlink peak): 127 Kbps

NB-IoT (Narrowband IoT) is one of two IoT communication protocols based on LPWA (Low Power Wide Area) networking technology. NB-IoT devices offer low prices, low power consumption, along with wide coverage and high capacity. The protocol allows for excellent indoor penetration. Thanks to optimized power consumption, batteries can last up to ten years. Since it runs on existing 4G networks, smart buildings need to be in the range of a provider network that has deployed this technology.

The main disadvantage of NB-IoT is for applications that require mobility. While NB-IoT works on mobile networks, it was not made to be mobile. To save power, devices only register with the mobile tower one time. Although devices could be forced to rescan and register in another location, the increased power consumption would take away one of the protocol’s most significant advantages.

U.S. Telecom providers T-Mobile and AT&T already have NB-IoT networks in operation. Across Europe, German operator Deutsche Telecom has taken their NB-IoT network deployment live as well. Other providers have networks in the works as well.


Standard: Zigbee 3.0 based on IEEE802.15.4

Channel Bandwidth: 600 kHz – 5 MHz

Data Encryption: AES 128

Frequency: 2.4 GHz  

Range: Approx. 10-100m

Data Rate (downlink peak):  250 kbps

Zigbee is a versatile and robust IoT communication protocol that can be found in home automation systems as well as in commercial and industrial applications. It has several features that make it a popular choice among IoT communication protocols for smart buildings. It offers data rates of 250 kilobits per second and is highly scalable. The protocol can handle wireless connectivity for all components of building automation like system controllers, lighting controllers, sensors, and more. Zigbee is secure as well, offering AES128 encryption, keys, and device authentication.

Because ZigBee operates on a self-forming, self-healing MESH network topology, it has excellent reliability. Each device is connected to multiple network nodes. Because of this, the protocol can also work far beyond the 100m range limitation by using the mesh to extend the network distance.

While an excellent choice for many applications, Zigbee does require a custom gateway to control smart devices. Since it operates on the same frequency as Bluetooth and Wi-Fi, it can also be prone to signal interference, especially in areas with heavy use of these frequencies.


Standard: Sigfox

Channel Bandwidth:  0.1 KHz (100 Hz)

Data Encryption: Private key, VPN+SSL

Frequency: 900Mhz

Range: 30-50km(rural environments), 3-10km(urban environments)

Data Rate  (downlink peak): 10 – 600bps

Among the IoT communication protocols, Sigfox is known for its extremely low power consumption. This feature makes it an excellent choice when devices need to run on battery and are difficult to access. Some of the power savings come from the move of all of the processing to the cloud requiring much less of the devices.

The Sigfox protocol is different from others in that devices are not connected to any specific node or base. They broadcast transmissions while base stations monitor the frequency spectrum to capture and decode the messages. This makes the protocol especially flexible able to quickly expand in scale and distance. It offers an extended range, especially in less dense rural areas.

If you need to move large amounts of data quickly, Sigfox is not the option you are looking for. The low power needs and extended distance come with very limited data rates. It is, however, designed to make the most of its low data rate by optimizing small data payload delivery. When wide-area coverage is needed, power is a concern, and small data rates aren’t an issue, Sigfox is an excellent solution.


Standard: LoRaWAN

Channel Bandwidth:  125 kHz

Data Encryption: 128-bit NwkSkey/ AppSkey

Frequencies: Various

Range: Approx. 2.5 km (Urban environment), 15 km (Suburban environment)

Data Rate  (downlink peak): 50 Kbps

LoRaWan (long-range radio wide area network) is designed specifically for IoT and offers lower power consumption over large areas. As a result, it is ideal for connecting a large number of battery-powered devices across local, regional, national, and global networks. In addition, it features bi-directional communication and end-to-end security. LoRaWan operates on unlicensed bandwidth frequencies and is currently being used in smart buildings as well as smart cities, agriculture, utility metering, and supply chains.

Due to limitations on channel occupancy, LoRaWAN does have some restrictions regarding the total number of devices on the network. The low bandwidth also makes it less than ideal for applications requiring low latency or transferring large amounts of data.


Standard: Bluetooth 4.2

Channel Bandwidth:  2 MHz

Data Encryption: AES-CCM, HMAC-SHA256, P256 ECDH

Frequency: 2.4GHz

Range: 50-150m (Smart/BLE)

Data Rate  (downlink peak): 1Mbps (Smart/BLE)

Bluetooth is a short-range communications technology primarily found in smartphones and other mobile devices. However, with the appearance of BLE (Bluetooth Low-Energy) and Bluetooth Smart, the protocol is gaining acceptance for commercial applications. Currently primarily used for location services and other uni-directional communication, the new Bluetooth Mesh increases the possible use cases for this protocol.

While this protocol offers many advantages, it was not designed for large file transfers. It is much more suitable for small chunks of data. There is also a limit on the number of connected devices, making it impractical for large installations.

Wirepas Mesh

Standard: Bluetooth 4.2

Channel Bandwidth:  2 MHz

Data Encryption: AES 128


Range: 20-40m indoors (NLOS), 150m outdoors (LOS)

Radio bandwidth: 1 Mbps

Wirepas Mesh is designed for large IoT networks. Wirepas Mesh handle millions, even billion, devices in one network. It can manage data collection, device control, and device-to-device communication.

The Mesh topology brings robustness to any network. On top of the basic mesh benefits, Wirepas Mesh handles the network independently – including network planning and re-routing.

Read Haltian & Wirepas joined article Massive IoT – What and why?

Devices with Wirepas Mesh continually monitor interference and automatically change frequency channels between devices for the best performance. For ease of installation and maintenance, battery-powered routers can run for over five years on a single battery.

Final words

So, here are the major IoT communication protocols used in smart buildings. Hopefully, these will help you in your journey in selecting the correct IoT solution for you! If you want to learn more about IoT solutions, head over to our other IoT resources.

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