CompTIA Security+ Exam Prep

Answer: A - TCP and UDP are the two main protocols that work at the transport layer. TCP is a reliable and connection-oriented protocol, thus it ensures packets are delivered to the destination computer. If a packet is lost during transmission, TCP has the ability to identify the issues and resends the lost or corrupted packet. TCP also supports packet sequencing, flow, congestion control, and error detection and correction. UDP is a best-effort and connectionless protocol. It has neither packet sequencing nor flow and congestion control, and the destination does not acknowledge every packet it receives.