More and more smart devices that utilize the Bluetooth Mesh protocol rather than the well-known ZigBee protocol have been hitting the market recently. Which has, naturally, prompted an increasing number of queries regarding which is superior and which to select.
The wireless protocols ZigBee and Bluetooth are commonly utilized for local Internet of Things (IoT) device linking, which is the cornerstone of the smart home. Everyone has unique qualities, benefits, and drawbacks.
In order to gain a deeper comprehension of the parameters governing these Internet of Things protocols, let us first examine the benefits and drawbacks of ZigBee, followed by the same for three distinct Bluetooth variants: BLE, BT Mesh, and the classic variant.
ZigBee is an open global standard for low-bandwidth, low-power wireless mesh networks that was created by an alliance of businesses known as the ZigBee Alliance. Via a mesh network of intermediary router nodes, the ZigBee protocol enables data transmission over comparatively large distances. ZigBee’s 2.4 GHz frequency range can be used anywhere in the world without the need for additional licensing.
Benefits of the ZigBee network
It is possible to build massive branching networks with ZigBee that are many times bigger than the combined range of any one of its nodes. When a node is disconnected or erased, a ZigBee network automatically forms and dynamically reconfigures itself to restore itself (self-healing).
The coordinator, which is a function of gateways, also known as hubs, and different ZigBee sticks is at the center of such a network.
Furthermore, routers—which include the great majority of stationary power (and zero line) devices like sockets, relays, switches, lights, etc.—play the role of nodes. Routers have the ability to form lengthy chains of links by connecting other routers through themselves.
The last devices are various sensors, switches, relays, and sensors without a zero line; once the chain of connections is severed, they are unable to transmit any more information. The ZigBee network’s energy efficiency enables them to operate on a single battery for many years.
Protocol documentation is widely accessible and includes information on a wide range of use cases. Significant development time is saved because security, retries, acknowledgments, routing and addressing tables, and retries are all integrated into the protocol.
ZigBee is widely used in home automation because it conforms to standards, which facilitate seamless communication between devices made by different manufacturers. The market offers a wide variety of hardware options at very affordable prices.
Negative aspects of the ZigBee network
ZigBee nodes, or message-routing routers, need to be powered on constantly, just like the majority of mesh networks. Although endpoints can extend their battery life by going into sleep mode, they are not part of the overall network as they are unable to relay messages from other nodes.
IP addressing is not used by ZigBee. As a result, in order to interact with cloud services, the internet, or smart home control centers, the gateways I previously mentioned are required.
A wireless networking protocol called Bluetooth was created for close-quarters communication. It was first designed to take the place of the cables that were used to link gadgets like computers and cellphones to their accessories like keyboards, mice, and headphones. It uses the same 2.4 GHz frequency band as Wi-Fi and ZigBee, which is open to all users worldwide without a license.
When long battery life is not required, Bluetooth Classic is designed to transfer data at up to 2.1 Mbps over short distances. For audio and video devices that need a lot of bandwidth and daily charging, this is a great solution. These consist of portable headsets, headphones, keyboards, mice, printers, and other accessories that are usually connected to a computer, smartphone, or car multimedia system. A master-client architecture is used by Bluetooth. Up to seven client devices can communicate with a single master.
Bluetooth Classic’s advantages
Bluetooth Classic’s large bandwidth will be useful if you need to send or receive a lot of data. This protocol is implemented by numerous devices. It is simple to connect your TV, laptop, tablet, or smartphone for streaming audio and video. The documentation for Bluetooth Classic is extensively available in books, online, and, of course, in the official standards documentation. Bluetooth Classic is a very developed protocol.
Bluetooth Classic’s limitations
The implementation of Bluetooth Classic can be highly intricate, necessitating manual pairing to oversee the procedure. It uses a lot of power because of its large bandwidth. The protocol is not appropriate for many Internet of Things applications because it is made for devices that can be charged regularly or have stationary power. Because the protocol was created to replace peripheral cables rather than scalable networks that can accommodate hundreds of devices, networks can only be very small.
Low bandwidth connections over short distances are supported by Bluetooth BLE Bluetooth Low Energy with exceptional energy efficiency. When batteries must last for months or even years and the network is not required to handle massive data streams, this method is employed. Devices that do not require a large amount of data bandwidth, such as smart watches, digital scales, humidity, temperature, light, and thousands of other items, are examples of BLE devices.
By implementing a server-client architecture, BLE conserves battery life and bandwidth by enabling the hardware to perform only the most essential communication functions. Although bandwidth, distance, and most importantly, range restrict the size of a single personal BLE network to a few hundred nodes, BLE networks have the potential to accommodate enormous numbers of devices.
Advantages of Bluetooth Low Energy (BLE)
The primary benefit is obvious from the name: Bluetooth Low Energy uses very little power. Because devices can run on batteries or tablets for extended periods of time, this protocol is recommended for small data transfer devices that must function independently for months at a time. Furthermore, BLE devices and chips are often less expensive than ZigBee.
By streamlining the implementation of communications, the server-client architecture shortens the time required for design and development. It also implies that devices can read and send data instantly and asynchronously when necessary, negating the need for pairing in order to communicate. Globally, the protocol is applied on billions of devices and is in widespread use.
Point-to-point protocols are used in BLE. As a result, network users are unable to communicate outside of their personal range. This restricts the physical size of networks to the standard BLE 10-meter range, which is adequate for small offices, apartments, and houses in general.
Similar to ZigBee, IP addressing is not supported here, necessitating the use of gateways; however, in contrast to ZigBee, multiple gateways may be active simultaneously.
The protocol known as Bluetooth Mesh (BT Mesh) is relatively new. By utilizing extra routing and network formation standards, it expands on the point-to-point architecture of BLE and creates mesh networks, where nodes can serve as repeaters to expand the network’s reach beyond that of a single device. In terms of functionality and architecture, BT Mesh and ZigBee are fairly similar, but there are a few key distinctions. Though, as with other protocols, practical bandwidth and physical space limitations usually restrict individual networks to a few hundred devices, a BT Mesh network can theoretically support over 32,000 nodes.
The benefits of Bluetooth Mesh Networks transcend beyond the individual node’s coverage area. Instead, a node’s ability to forward and route messages to recipients located well outside of its own range allows it to form very large physical networks. Since Bluetooth Mesh is built on the BLE protocol, it benefits from many of its features, such as strong security, low power consumption, support for beacons, and a wealth of basic documentation. Like ZigBee, BT Mesh networks are repeater-to-point and self-forming. They also allow end devices to hibernate while the network remains connected.
Bluetooth Mesh’s limitations
As a relatively new protocol, Bluetooth Mesh is still undergoing development and improvement. Although things are moving in the right direction, gateways, repeaters, and end devices are still not entirely interoperable because it is not as widely supported as ZigBee.
As BT Mesh routers are not permitted to hibernate like ZigBee routers, any device that performs routing must be powered by the network rather than a battery. Since they don’t use IP addressing, external communication has to go via fixed gateways that translate the BLE protocol to the standard Internet protocol. Because messages may pass through several nodes en route to their destination, mesh networks inherently have higher latency. As a result, applications using mesh networks must be prepared to endure longer response times in exchange for the network’s increased scalability.
What’s the final result?
Both Bluetooth and ZigBee are helpful in a wide range of IoT applications. Most importantly, they can cooperate to build incredibly versatile applications that combine each protocol’s advantages. Nowadays, ZigBee dominates the market in terms of availability; a wide variety of sensors, including end devices, routers, and fixed-powered devices, are available. Although Bluetooth mesh is still in its early stages of development, an increasing number of new IoT devices that support it are hitting the market.