Which protocol is characterized as connection-oriented?

The protocol characterized as connection-oriented is TCP (Transmission Control Protocol). TCP establishes a connection between the sender and receiver before transmitting data, ensuring that data is delivered reliably and in the correct order. This process involves a three-way handshake, which prepares both endpoints for communication and confirms that they are ready to exchange data. TCP also incorporates error-checking and flow control mechanisms, which further enhance its reliability. This connection-oriented nature is crucial for applications where data integrity and order are important, such as file transfers and web browsing.

In contrast, UDP (User Datagram Protocol) is a connectionless protocol that sends messages without establishing a connection, leading to faster transmission but without guarantees of delivery or order. HTTP (Hypertext Transfer Protocol) is an application layer protocol that usually runs on top of TCP but is not inherently connection-oriented by itself; it utilizes TCP for its connection-oriented features. FTP (File Transfer Protocol) is another application layer protocol that relies on TCP for reliable connections but is not a connection-oriented protocol by itself; rather, it operates over the underlying TCP connections.

Thus, TCP’s characteristics of establishing a connection, ensuring reliable data transfer, and managing data order classify it as connection-oriented.