What is difference between node JS and AngularJS?
Angular and node are Both the open-source tools as node.js is mainly used to build server-side applications, whereas AngularJS is suited for building single-page client-side web applications both can be combined to create isomorphic web applications.
CoAP Vs. MQTT
An important aspect to cover is the main differences between CoAP and MQTT. As you may know, MQTT is another protocol widely used in IoT. There are several differences between these two protocols. The first aspect to notice is the different paradigm used. MQTT uses a publisher-subscriber while CoAP uses a request-response paradigm. MQTT uses a central broker to dispatch messages coming from the publisher to the clients. CoAP is essentially a one-to-one protocol very similar to the HTTP protocol. Moreover, MQTT is an event-oriented protocol while CoAP is more suitable for state transfer.