Which transport layer protocol is connection-oriented and guarantees reliable, ordered delivery of data between two hosts?

TCP (Transmission Control Protocol) is connection-oriented. It establishes a connection via a three-way handshake, then guarantees reliable, ordered delivery using sequencing, acknowledgments, and retransmission of lost packets. UDP is connectionless and offers no delivery guarantees, making it faster but unreliable. IP is a network-layer protocol responsible for addressing and routing, not reliability. ICMP is used for diagnostics and error reporting (e.g., ping), and ARP resolves IP addresses to MAC addresses — neither handles end-to-end data transport.