Highlights of Bluetooth Mesh Technology

朗锐智科

Highlights of Bluetooth Mesh Technology [Copy link]

Bluetooth is one of the most dominant low-power wireless technologies today and is very familiar to wireless device users and developers. Prior to last summer, Bluetooth network types were limited to two-way communication between two devices, beacons or a single hub and several satellite devices that could only communicate with that hub (a star network). While beacons are a one-to-many broadcast-based technology for point-of-interest information delivery—indoor positioning, asset tracking, and two-way communication create many possibilities for Bluetooth IoT use cases, the latest Bluetooth updates have evolved into the next generation of network architectures. Last summer, the Bluetooth Low Energy (LE) standard was upgraded with the option of mesh as a new network topology. The key to Bluetooth mesh is that each node is able to act as a viable operator in the network and also relay messages from other nodes in the network. With one or more nodes connected to the internet, a Bluetooth mesh network can seamlessly become an Internet of Things (IoT) network that is easily scalable and relatively simple to develop. Where Bluetooth Mesh Shines In a traditional star network, each satellite node must be connected to a central node. While suitable for well-defined static and small networks, the limitations of this network topology make expansion, development, mobile and dynamic networks unfeasible due to cost and design challenges. Another limitation of the star network topology is also range, as each satellite node must be able to get back to the central node in order for the star network to operate. However, with a mesh, multi-hop communication allows any viable node in range to resend a node message to any node that requires it. This is where Bluetooth mesh shines, as mesh network topologies can be designed to scale to large numbers - currently specified as 32,000 nodes - and adapt to changing network conditions.391408 Scalability and Reliability of Bluetooth Mesh NetworksWith the IoT revolution taking place in nearly every industry, many applications that previously relied on hardwired reliability but suffered from tough scalability issues are beginning to adopt wireless solutions. These applications benefit from low-power mesh technology because the scalability of such systems is unprecedented compared to hardwired and traditional point-to-point wireless systems. More importantly, meshes are also not subject to the reliability issues that plagued previous point-to-point wireless systems. Scalability in Bluetooth mesh is a developer concern, enabling a mesh network to grow based on the nodes that are configured to operate with that network. Provisioning can be done as a very secure multi-authorization method, or as simple as a user choosing to push a virtual smartphone button. As a result, mesh deployments can be done in a large single installation, or nodes can be added as additional network coverage, sensor density, or other scenarios that benefit from additional nodes are required. Additionally, through the Generic Attribute Profile (GATT), standard Bluetooth LE devices can communicate with a Bluetooth LE mesh network through a proxy node, further allowing the mesh network to scale as needed. Where point-to-point and wired network types typically revolve around a single hub, with each connection to the hub and the liabilities of the hub infrastructure, mesh network topologies can utilize each node in the network as a potential communication link, or hub (relay node). This enables self-healing and route optimization, which improves the reliability and efficiency of mesh networks compared to star networks. This feature is known as multipath delivery, where messages can be sent from one node and received by the end receiver through various paths in the mesh network. Bluetooth Network Interoperability and Low Energy Beacons Interoperability is a major concern for many new standards and technologies, as it can alienate or allow portions of existing technologies that are still viable to become obsolete. However, with Bluetooth mesh, previous versions of Bluetooth LE, such as those found in smartphones and tablets, can still communicate with Bluetooth mesh over GATT. Proxy nodes are simply Bluetooth mesh nodes that have been approved to connect to other Bluetooth LE devices, enabling two-way communication with the Bluetooth mesh. A significantly growing use case for Bluetooth LE is beacons. Beacons are events that trigger a node to transmit information, which may include sensor information, location, or point of interest information. There are two main beacon standards on the market: iBeacon from Apple and EddyStone from Google, each with individual benefits and use cases. Now, any Bluetooth mesh node can include one or both beacon standards and can become a virtual Bluetooth beacon when operating as a Bluetooth mesh node. This can enable new use cases and even business models, such as connected indoor lighting vendors, which are now starting to offer new services such as indoor positioning, asset tracking, and point of interest information delivery. Star networks require a centralized hub to operate, where mesh networks can utilize nodes within the network to relay messages to improve scalability.

Benefits for Bluetooth Mesh Developers

Fortunately for developers who already have a mature BluetoothLE stack and deployment, Bluetooth mesh is complementary to the established BluetoothLE protocol. Using a vendor's Bluetooth meshSDK, a mesh network can be quickly developed and optimized for a given application, and developers familiar with previous Bluetooth versions and theSDK can do so with ease. In addition, previous technologies can communicate with new Bluetooth mesh devices overGATT, meaning that only technologies that require mesh capabilities require mesh development. Finally, like many Bluetooth devices, user device setup and configuration can be easily accomplished through a smartphone/tablet and app interface. The versatility of the Bluetooth stack enables Bluetooth mesh networks to communicate with Bluetooth LE devices, such as user/customer smartphones/tablets, through proxy nodes in the mesh network. Bluetooth Mesh and Home Automation Smart light bulbs, thermostats, vents, motion sensors, and many other smart home IoT applications are growing in popularity. Typically, these home automation devices use a variety of different wireless standards and technologies and require a variety of interconnected hubs and network routing throughout the home. Bluetooth mesh holds promise as a protocol to simplify the smart home automation process, making it easy to set up and configure a mesh network of devices through a user's smartphone or tablet. The benefit to the user is that a mesh network of connected devices can be used to relay messages over multiple paths, which increases both reliability and network coverage. With just a few nodes, Bluetooth mesh can reach every corner of a large home and prevent service interruptions if a single node fails. For example, if some of the nodes in a home lighting Bluetooth mesh are connected to the home network, even if one of the home network-connected nodes fails, messages from the remaining mesh can still reach the user's control/reporting devices. Traditionally, if a hub fails, the entire network becomes unusable. This could literally be the difference between a light being on and off. Bluetooth Mesh in Retail, Smart Building, and Warehouse Automation Applications Many commercial and industrial environments are benefiting from IoT enhancements. Some of these applications include asset tracking, location service beacons, advanced lighting controls, environmental monitoring, patient monitoring, and other automation functions. What Bluetooth Mesh is able to do is simplify the deployment of a multi-functional network that is capable of massive scalability without modifying the network's underlying infrastructure. This is quite powerful potential given that many wireless communication technologies require complex development or separate networks to perform multiple functions.

For example, a single Bluetooth mesh network can support enhanced customer information and interaction services and asset tracking beacons in a retail store warehouse, while supporting both asset tracking and beacons reporting the status of store shelves. Such an integrated system can go beyond simple low-shelf inventory reporting and can actually be used to automatically direct employees to the exact location of an item in the warehouse and then back to the shelf or location of a potential customer’s interest discovered on a smartphone.

Bluetooth mesh can also be used in low-latency scenarios. Current Silicon Labs benchmarks indicate that Bluetooth mesh solutions can achieve sub-10 milliseconds per hop latency with a single packet payload of up to 11 bytes of data (test data has demonstrated a 6-hop round-trip latency of approximately 110 milliseconds, or 55-ms one-way latency). Of course, latency increases as the network or payload size increases. Fortunately, for some applications, network size has a smaller impact on latency than payload size. This means that specific networks can be optimized using functional nodes and relay nodes to reduce network latency while maintaining coverage and reliability. Silicon Labs benchmarks also show that large Bluetooth networks can perform well. Although Bluetooth mesh has only recently become available with chipsets and SDKs from manufacturers and will likely benefit from future enhancements to the standard, mesh networking with the Bluetooth standard will offer many unique capabilities for home, commercial, and industrial automation. These benefits include Bluetooth mesh’s ability to easily develop and deploy scalable mesh networks that are highly reliable and can be easily used to perform multiple tasks. This capability is further enhanced by the fact that Bluetooth mesh networks can be composed of nodes with various capabilities, such as friend nodes that support low-power nodes and proxy nodes that enable intercommunication between Bluetooth mesh and non-mesh Bluetooth LE devices. Given the flexibility and ease of development, the Silicon Labs EFR32BG Bluetooth Development Kit is the easiest and fastest way to start building your own BLE applications. Designed to speed up evaluation time, the kit features a powerful EFR32 Blue Gecko module.5pt]Bluetooth Mesh in Retail, Smart Building and Warehouse Automation Applications

Many commercial and industrial environments benefit from IoT enhancements. Some of these applications include asset tracking, location service beacons, advanced lighting control, environmental monitoring, patient monitoring and other automation functions. What Bluetooth mesh is able to do is simplify the deployment of a multifunctional network that is capable of massive scalability without modifying the network’s underlying infrastructure. This is quite powerful potential given that many wireless communication technologies require complex development or separate networks to perform multiple functions.

For example, a single Bluetooth mesh network could support enhanced customer information and interaction services and asset tracking beacons in a retail store warehouse, while supporting both asset tracking and beacons reporting the status of store shelves. Such an integrated system could go beyond simple low-shelf inventory reporting and could actually be used to automatically direct employees to the exact location of an item in the warehouse and then back to the shelf or location of a potential customer who has found interest on a smartphone.

Bluetooth mesh can also be used in low-latency scenarios. Current Silicon Labs benchmarks indicate that Bluetooth mesh solutions can achieve sub-10 milliseconds per hop latency with a single packet payload of up to 11 bytes of data (test data has demonstrated a 6-hop round-trip latency of approximately 110 milliseconds, or 55-ms one-way latency). Of course, latency increases as the network or payload size increases. Fortunately, for some applications, network size has a smaller impact on latency than payload size. This means that specific networks can be optimized using functional nodes and relay nodes to reduce network latency while maintaining coverage and reliability. Silicon Labs benchmarks also show that large Bluetooth networks can perform well. Although Bluetooth mesh has only recently become available with chipsets and SDKs from manufacturers and will likely benefit from future enhancements to the standard, mesh networking with the Bluetooth standard will offer many unique capabilities for home, commercial, and industrial automation. These benefits include Bluetooth mesh’s ability to easily develop and deploy scalable mesh networks that are highly reliable and can be easily used to perform multiple tasks. This capability is further enhanced by the fact that Bluetooth mesh networks can be composed of nodes with various capabilities, such as friend nodes that support low-power nodes and proxy nodes that support intercommunication between Bluetooth mesh and non-mesh Bluetooth LE devices. Given the flexibility and ease of development, the Silicon Labs EFR32BG Bluetooth Development Kit is the easiest and fastest way to start building your own BLE applications. Designed to speed up evaluation time, the kit features a powerful EFR32 Blue Gecko module.

star_66666

Very good analysis