VPS+ introduces two components:
The configuration specifies what a protocol stack looks like. It is typically built on a controller. For example, the following is a stack that represents a web server:
The configuration is deployed on the target device and becomes its communication stack.
Most times, the stack is not enough to provide full functionality. In those cases, coding is needed. VPS+ relies on a scripting infrastructure based on LUA programming. LUA is lightweight and highly optimized to run on highly constrained embedded IoT devices. For example, the following piece of LUA code runs together with the web server stack above:
The script is run either on the device or on the controller itself. If the script runs on the device, the device can become autonomous. If the script runs on the controller, the controller drives this and other devices real-time.