IoT (Internet of Things) devices are able to communicate and interact with other devices without having a physical connection. The question is: will you connect these devices using Bluetooth or Wi-Fi?
Both Bluetooth and Wi-Fi are commonly used for IoT devices, but there are advantages and drawbacks to both choices because they operate in different ways. In this article, we’ll discuss the question of Bluetooth vs. Wi-Fi as it pertains to IoT.
Bluetooth IoT Devices
Bluetooth is a wireless technology protocol that relies on physical proximity in order to manage the connections between devices, without the need for a password. The Bluetooth standard uses UHF (ultra high frequency) radio waves between 2.400 and 2.485 GHz, which can extend a maximum of 164 feet between two devices.
Examples of Bluetooth technology include Apple’s wireless headphones AirPods, as well as many wireless devices such as speakers, computer mice, and keyboards.
Bluetooth IoT Compatibility Requirements
In order to be compatible with Bluetooth, an IoT device must have a microprocessor that can handle Bluetooth, as well as a second device to pair with it. The Bluetooth protocol actually has two different versions commonly used by IoT devices that cannot directly communicate with each other: Bluetooth Classic and Bluetooth Low Energy (BLE), which is designed for devices that need to consume low amounts of power.
There are several reasons why developers might choose to use Bluetooth instead of Wi-Fi for IoT devices. First, Bluetooth usually requires physical proximity to initiate a signal broadcast, so there is no possibility of remote attacks. Second, Bluetooth requires much less energy than Wi-Fi, so it works better for low-power IoT devices such as basic sensors.
Wi-Fi IoT Devices
Wi-Fi is a wireless networking technology that uses various bands of radio waves to transmit information between devices. All modern computers and smartphones come with built-in Wi-Fi capability.
Wi-Fi IoT Compatibility Requirements
In order to use Wi-Fi on an IoT device, you just need a microchip, which is easy and cheap to obtain. However, in practice you also need firmware to manage the device’s Wi-Fi credentials, since Wi-Fi is a very large attack vector for malicious actors.
Generally, IoT devices that use Wi-Fi are large, stationary hubs, although they can be smaller devices as well. To use Wi-Fi, an IoT device needs to be close to a Wi-Fi access point (i.e. not located far afield).
IoT Bluetooth vs. Wi-Fi: Feature Comparison
Now that we’ve discussed the basics of both Bluetooth and Wi-Fi, let’s go over how the two technologies stack up in terms of different features.
Wi-Fi has a maximum speed that is much faster than Bluetooth: at least 54 Mbps for Wi-Fi, vs. only 3 Mbps for Bluetooth. As a result, Bluetooth is typically used for transferring small chunks of data, such as the numerical values from IoT sensors. Wi-Fi, on the other hand, is better for sending large data files, such as videos and photos.
2. Security and privacy
The security in Bluetooth is sufficient for most purposes, although it’s not intended to be a secure protocol in and of itself. However, using Wi-Fi can help if you’re concerned about sensitive data transmission. Wi-Fi can add an additional layer of security by using a security protocol such as WEP, WPA, WPA2, and WPA3 (the latest and preferred version of WPA).
3. Location detection
The right answer here will depend on the accuracy and precision required from your use case. Both Wi-Fi and Bluetooth can provide accurate location information, although Bluetooth may be somewhat more reliable in certain instances.
4. Proximity detection
The proximity data provided by BLE is much more accurate than Wi-Fi, but still not very accurate either. (We’re talking an estimate that’s accurate not within inches, but perhaps within dozens of feet.)
Bluetooth typically has a smaller range than Wi-Fi. Class 1 Bluetooth devices are expected to have a maximum range of 100 meters (328 feet), but most consumer Bluetooth devices have a range less than this—often just 10 meters (33 feet). In addition, the range of Bluetooth will depend on the obstacles and the density of the walls in between two devices. Wi-Fi range also varies depending on factors such as frequency, transmission power, antenna type, and environment; Wi-Fi routers located outdoors typically have a much larger range.
6. Power usage
If you use Wi-Fi, you may need to include an additional directly connected power source for your device. Bluetooth was designed to use less power than Wi-Fi, especially with the BLE protocol.
Bluetooth vs. Wi-Fi for IoT: Which is Better?
As we’ve discussed, there’s no clear winner when it comes to Bluetooth vs. Wi-Fi for IoT. Your best choice will depend largely on your business needs and priorities and how your device will be used.
Note that technically, it’s not possible to have an IoT device that only uses Bluetooth, since it still requires an intermediary device that will broadcast the data it receives using Wi-Fi.
In general, Bluetooth is better for mobile devices that have limited power requirements. Meanwhile, Wi-Fi is better for larger, more stationary devices that need a direct connection to the Internet.
Best Option for IoT Devices
When it comes to the question of Bluetooth vs. Wi-Fi for IoT, the right answer will depend on the specifics of your situation. Consulting with a knowledgeable IoT development firm can help you make the best connectivity decision for your product.
Here at Very, we build IoT devices that use the best communications technology for their use cases, including both Bluetooth and Wi-Fi. To learn more about how we approach the IoT development process, check out our complete guide to IoT development.