Which of the following is a connection-oriented packet-switched network service?

The correct answer is Frame Relay because it operates as a connection-oriented service within a packet-switched network. In connection-oriented communication, a dedicated path is established before any data is transferred, which allows for consistent and reliable data transmission. Frame Relay achieves this by creating a virtual circuit that helps manage data flow and ensures that packets arrive in the correct order.

Frame Relay allows for multiple virtual circuits over a single physical connection, providing a flexible and efficient way to transfer data between networked devices. It is designed primarily for data transport and uses error-checking and control mechanisms that enhance the communication reliability, which are characteristic features of connection-oriented services.

In contrast, other options represent different networking approaches. Token Ring operates on a token-passing method over a physical ring topology and doesn’t establish a dedicated connection. Ethernet is primarily a connectionless protocol that sends packets without prior arrangement or connection setup. Lastly, IPX/SPX is a protocol suite used primarily in Novell networks and is also connectionless, meaning that it does not establish a persistent connection before transmitting data. These differences distinguish Frame Relay as the only connection-oriented service among the choices.