Smart Factories and the Challenges of the Proximity Network
Data Reliability- The network stack on the edge-device is necessary to implement reliable data transfer. In the case of battery-operated devices, the application on the edge needs to be much smarter to reliably transmit data.
4.2 IIoT Gateway
The IIoT gateway plays an important role in distributing intelligence in the IIoT application due to its location as a proxy between the edge devices and backhaul. Additionally, it generally carries more processing power than edge devices allowing for an increase in local decision making.
Powering the Edge Device- Battery-operated devices generally need the higher horsepower of the gateway to aid in the reliable data collection. In many instances, software on the gateway coordinates the sleep / wake periods of the edge devices and ensures that data is reliably delivered.
Integrating with IT- The gateway provides a prime location to shield the IT department from the networking complexities of the edge network. It can do this in the form of protocol conversion or in the form of presenting the sensors and proximity network as a service to IT. As IIoT becomes more prevalent, we will likely see the proximity network, gateway and edge devices less as a point solution and more as a service to be shared among multiple applications.
Data Bandwidth- The gateway also manages the utilization of the backhaul network. Cellular backhaul in particular often requires aggregation logic on the gateway such as summing and threshold-crossing detection to limit the utilized bandwidth.
Data Reliability- The gateway can play a key role in data reliability not only for battery-operated edge devices, but also for wired-power devices. In cases where the backhaul network is unavailable, the gateway can maintain the data collection and even some of the application logic until connection is restored.
5. DEPLOYMENT
In many cases, the IIoT solution design considers the connectivity and development concerns, but fails to account for deployment until the solution is being installed. The choices made on connectivity and distributed intelligence drive the set of deployment issues.
5.1 Connectivity
The networking approach in the proximity network dictates much of the deployment problems. Wired Ethernet often requires electrical work and some IT work for switch setup. Wireless installation often requires some site survey to make sure that signal strength and interference are at appropriate levels. Additionally, the edge devices must have the correct security credentials and networking parameters provisioned to make them easy to install securely. These credentials can be programmed at manufacturing time or via an installation application or some combination of both.
- 74- January 2017