Complex sentence: Connection-oriented Ethernet refers to a set of technologies that turn Ethernet, a Connectionless protocol by design, into a Connection-oriented protocol, with the aim of combining the flexibility and cost-efficiency of Ethernet with the reliability of connection-oriented protocols.
Split into simpler sentences: Connection-oriented Ethernet refers to the transformation of the Ethernet computer-networking protocol, a Connectionless protocol by design, into a Connection-oriented protocol. The aim of Connection-oriented Ethernet is the generally the creation of a networking technology that combines the flexibility and cost-efficiency of Ethernet with the reliability of connection-oriented protocols.