Concept:Stateless Protocols are the type of network protocols in which the client sends the request to the server and server response back according to the current state.It does not require the server to retain session information or status about each communicating partner for multiple requests.Application Layer protocol: HTTP and DNSTransport Layer protocol: TCP and UDPStateless protocol: HTTP, UDP, DNSExplanation:UDP is an unreliable connectionless-transport layer Protocol used for its simplicity and efficiency in applications where error can be provided by the application layer. UDP provided process-to-process communicationImportant Point:UDP (User Datagram Protocol) ? transport layer protocol ? connectionlessTCP (Transmission Control Protocol) ? transport layer protocol ? connection-orientedFTP (File Transfer Protocol) ? Application layer protocol ? connection-orientedNVT ? Network Virtual Terminal ? Application Layer Protocol ? connection-oriented