Constrained Application Protocol (CoAP) is an IoT protocol that is
specifically designed for M2M data exchange between constrained devices
(such as microcontrollers) in constrained networks.

The interaction model of CoAP is similar to the client/server model of
HTTP, but unlike HTTP, it uses datagram-oriented connectionless transport
such as UDP, which leads to a very low overhead and allows UDP broadcast
and multicast to be used for addressing. At the same time it provides
lightweight reliability mechanisms and security.

Qt CoAP implements the client side of CoAP. By default, the transport
layer uses QUdpSocket and QDtls for security. Alternative transports can
be used by implementing the QCoapConnection interface.