The correct answer is: B. Request Response
A WebSocket is a full-duplex communication protocol that enables two-way communication between a client and a server. It is based on the TCP protocol and uses a persistent connection to keep the communication open. This allows for real-time communication between the client and the server, without the need for the client to constantly send requests to the server.
A WebSocket connection is initiated by the client by sending a WebSocket handshake request to the server. The server then responds with a WebSocket handshake response, and the connection is established. Once the connection is established, the client and the server can send messages to each other in either direction.
The WebSocket protocol is often used for real-time applications such as chat, gaming, and video streaming. It can also be used for other applications that require two-way communication between the client and the server, such as stock tickers and weather updates.
The other options are incorrect because they do not describe the WebSocket protocol accurately.
- Option A, Publish-Subscribe, is a communication model in which publishers send messages to subscribers. Subscribers can subscribe to multiple publishers, and they will receive all messages that are published by those publishers. The WebSocket protocol does not use the Publish-Subscribe model.
- Option C, Push-Pull, is a communication model in which a server pushes data to a client. The client does not need to request the data; the server will send it to the client regardless. The WebSocket protocol does not use the Push-Pull model.
- Option D, Exclusive Pair, is a communication model in which two devices communicate with each other using a single channel. This model is often used for point-to-point communication, such as in a phone call. The WebSocket protocol does not use the Exclusive Pair model.