In a classical network setup, the hub is the centralized decision-making point. The user can interface with the hub through a smartphone app or computer terminal, and the hub may be connected to the cloud so that remote actors can establish communications with the network’s central point.
Diagram of a hub and spoke network. Screenshot courtesy The Berkman Center for Internet and Society at Harvard University, used under CC BY license.
Hub and Spoke Networks get their name because, topologically, they look like a hubbed wheel. In these centralized networks, the nodes on the network are like spokes, each independently connecting to the hub. The nodes don't interact directly, but instead route all communications through the hub.
This setup works well in small offices or average-sized homes, but as the number of connected devices in use expands rapidly, a more robust network configuration will be needed to move that data from the device to the hub.
Mesh networks allow each point on the network, known as nodes, to attempt communication with all of the other nodes, and not only the hub. The utility of this network is that if a node is too far away from the hub, it can communicate to another node. If that node is also too far from the hub, it transfers the message to yet another node, until one is reached that can finally establish a connection to the hub.
Diagram of a mesh network. Screenshot courtesy The Berkman Center for Internet and Society at Harvard University, used under CC BY license.
Likewise, a message sent from the hub will be relayed along nodes until it reaches the far edge of the network. In this way, a large number of devices can share an internet connection, or devices can communicate directly without going through the internet. Having a variety of communication paths gives mesh networking several further advantages:
- The radio signal from the hub doesn’t have to be powerful enough to reach every far off node on the network.
- Each node doesn’t have to put out a signal powerful enough to reach the hub. This can be a decisive advantage for IoT applications, where low power requirements are critical.
- Nodes can communicate directly with each other without intervention of the hub. This can be an enormous advantage if latency is an issue. It also removes significant supervisory burdens from the hub.
- Steel, and other materials, can block radio waves. The point-to-point connectivity of a mesh network can skirt barriers, so no node is isolated.
New Products for Mesh Networking
Because of the advantages in ease of building a network, speed of communication, and implementation in sometimes difficult settings, several companies have entered the mesh networking sphere with new products.
Produal, a provider of building automation solutions, recently announced Produal Proxima, a cloud-based building automation solution, based on the NINA-B1 series of Bluetooth low energy modules and LumenRadio’s embedded operating system, MiraOS.
The Produal Proxima. Image courtesy Produal.
The u-blox NINA modules contain ARM Cortex-M4 microcontrollers, yet they offer battery lives of over eight years.
The BlueNRG-Tile from STMicroelectronics delivers Bluetooth Mesh Networking via a very small 2.5 cm package that requires only 900 nA in sleep mode.
BluetoothNRG-Tile all-in-one sensor node. Image (modified) used courtesy of STMicroelectronics.
Through the Bluetooth mesh network, the BlueNRG-Tile utilizes multiple sensors to communicate with smartphones. It also comes ready for quick deployment with a software development kit.
u-blox NINA-B3 modules
u-blox offers many lines of Bluetooth low energy (BLE) modules besides the NINA-B1. The NINA-B3 modules are designed with printed antennas within small packages.
The u-blox NINA-B306 and NINA-B316 modules. Image courtesy u-blox.
The new NINA-B306/316 modules eliminate the need for an external antenna by including a trapezoidal printed antenna. u-blox aims the modules for use in a wide range of applications, including IoT, automotive, healthcare, and intelligent buildings.
Specific Use Cases and Products
Mesh Networks for Ships
It’s difficult to establish networks for large ocean-going ships. There are far too many nodes to be connected by cabling. Steel bulkheads can block radio waves, so a classical hub and spoke network is out of the question.
Scan Reach Technology has developed In:Range, a mesh networks solution for ships. All personnel will carry ID tags that will be able to reach a node wherever (s)he may be. It will ensure that all hands will be where they are assigned to be at all times. And, in the event of an emergency, all aboard can be located in real-time with no delay. The information can be relayed via the cloud to rescue operators, with the potential reduce confusion and to save lives.
A related system, In:Connect, is for data harvesting from anywhere and anything on board. The data will be available to on-board personnel, and to relevant parties via the cloud.
The earlier-mentioned Produal Proxima, utilizing LumenRadio’s MiraOS, is capable of connecting hundreds of nodes, be they sensors, actuators or other gateways in a self-healing network. This means that if one node fails, another one is seamlessly found to take its place. MiraOS continuously searches for the best frequency with the least traffic to ensure reliable and optimal communication on the network.
Furthermore, building automation can be implemented without worry of future changes. If the layout of the building is altered or if new sections are added, the network will reestablish itself to the new layout. The network also carries out firmware-over-the-air updates to ensure all nodes are operating on the latest firmware.
Mesh Networks at Home
It’s the same old problem – your WiFi signal can’t reach every nook and cranny of your home. To counter this deficiency, Amazon has purchased Eero, a small outfit that specializes in home-based mesh networking.
In the highly-competitive field of home automation solutions, mesh networking may provide an advantage, since Alexa will be able to command nodes even if they are located in remote areas of your home. And, of course, Alexa-based speakers can be placed anywhere that the homeowner likes.
The 5G Wildcard
The specs are still nebulous, but there are a few things that are certain about 5G. One of them is that 5G won’t only be about communications between devices and the cell towers, but between device and device without any interaction with the tower or the cloud. The future of many things, especially the much-touted autonomous car, depends on it.
When this promise becomes a reality, mesh networking will be turned on its head, because the facility will be contained within 5G. It all depends on how it will be priced for individual nodes, and just how much more penetrating the 5G signal will be when compared to today’s 4G.
Have you worked with a mesh network before? What other use cases or possibilities do you see with mesh networking? Let us know in the comments.