CoAP is binary HTTP (solid request / response), with extras: - async reception (consider like a socket, really just a long lived multiple response to a GET) us

CoAP is binary HTTP (solid request / response), with extras: - async reception (consider like a socket, really just a long lived multiple response to a GET) using the Observe feature - Optional responses - block transfers, handy way to reliably send large files over UDP - built-in proxy options - ability to one to many with a multicast - because it extends HTTP first; it’s pretty easy to translate it to HTTP - CoAP extends easily, like OSCORE or LwM2M for end to end encryption or other features - Happy to transfer over datagram/UDP, TCP, MQTT, Dixie cups and string, etc As where… MQTT 3.1.1 has almost none of these features, with MQTT v5 finally adding some in. But MQTT v5 is also not really supported well.