CoAP

Meaning

Specialized internet protocols enable resource-constrained devices to communicate over the web using minimal power and bandwidth. The lightweight design of coap allows microcontrollers with small memory footprints to exchange state information with remote servers. This protocol is tailored for machine-to-machine applications and is not used for high-throughput multimedia streaming.

Resource Efficiency

Low overhead is achieved by using a binary header format that reduces packet sizes compared to text-based alternatives. Running coap on top of the user datagram protocol avoids the complex connection establishment required by transmission control protocol. This design choice minimizes the energy required to transmit sensor readings from battery-powered wireless nodes.

Message Transmission

Asynchronous exchanges support both confirmable messages that require an acknowledgment and non-confirmable messages that do not. If a critical temperature alarm must be sent, coap ensures delivery by retransmitting the packet if no response is received within the expected window. This mechanism allows the remote sensor to remain in a deep-sleep state until an event triggers a transmission.

This reliable delivery channel works efficiently even over unreliable wireless connections that have high packet loss rates.

Secure Communication

Transport layer security is adapted to work with datagrams to protect the integrity of the transmitted sensor data. The protocol relies on datagram transport layer security to authenticate the remote server and encrypt the payload. This security layer prevents unauthorized entities from intercepting the wireless commands sent to the industrial actuators.