# Cloud Connectivity
MQTT is an OASIS standard messaging protocol for the Internet of Things (IoT). It is designed as an extremely lightweight publish/subscribe messaging transport that is ideal for connecting remote devices with a small code footprint and minimal network bandwidth.
# Sparkplug B
Sparkplug is an extended public protocol based on the MQTT protocol designed for industrial IoT, especially industrial 4.0 distributed applications. Devices and sensors at the edge of a network can use Sparkplug B to communicate with applications like SCADA systems, historians, and analytics programs.
WebSocket makes the data exchange between the client and the server easier, allowing the server to actively push data to the client. In the WebSocket API, the browser and the server only need to complete a handshake, and a persistent connection can be established between the two, and two-way data transmission can be performed.
# RESTful API
API, full name Application Programming Interface (application programming interface), in simple terms, is an interface developed by the brand, allowing third parties to additionally develop and apply the system communication interface to their own products.