Final answer:
Sockets and connections are used to echo back incoming character strings from an echo client in an interactive echo server. Sockets act as endpoints for communication between computers, and connections are established through sockets. Data received by the server through the socket is sent back to the client as a response.
Step-by-step explanation:
In an interactive echo server, sockets and connections are used to echo back incoming character strings from an echo client. Sockets are endpoints for communication between two computers, and they facilitate data transmission over a network. Connections are established between the server and client through sockets.When an echo client sends a character string to the server, the server receives the data through its socket. It then sends the same data back to the client by writing it to the socket. This way, the client receives the echoed string as a response.For example, consider a Python echo server:import socketHOST = 'localhost'PORT = 12345with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as server_socket: server_socket.bind((HOST, PORT) server_socket.listen() print('Server listening on', HOST, PORT)while True: client_socket, address = server_socket.accept()print('Connected by', address) data = client_socket.recv(1024) client_socket.sendall(data client_socket.close()
The interactive echo server referenced in the question uses sockets and connections to receive and send back data to an echo client. When the server is started, it sets up a socket to listen for incoming connections. Upon receiving a connection request from a client, the server accepts the connection, thus establishing a communication pathway. Once the connection is established, the server enters into a loop where it reads character strings sent by the client and then sends them back unchanged, achieving the 'echo' functionality. This loop continues until the connection is closed either by the client or the server. The process of echoing back the data demonstrates the basic mechanism of a server responding to client requests in a network environment.