Reliable ordered delivery versus fast connectionless datagrams.
TCP provides reliable, ordered, connection-oriented delivery with handshakes, acknowledgements, retransmission, flow and congestion control. UDP is connectionless, low-overhead, unreliable: suited to streaming, gaming, DNS, VoIP. QUIC builds reliable transport over UDP.
A file transfer uses TCP; a live video call uses UDP.
TCP and UDP offer different trade-offs between reliability and speed, so the choice affects how applications behave under loss.
Reliable ordered delivery versus fast connectionless datagrams.
TCP and UDP offer different trade-offs between reliability and speed, so the choice affects how applications behave under loss.
When low latency matters more than guaranteed delivery, such as streaming, voice and some sensor telemetry.
It uses sequence numbers, acknowledgements, retransmission and flow control, so data arrives in order and without gaps.
Typical applications include using TCP for a file transfer where every byte must arrive, using UDP for live video or game updates where delay matters more than loss and designing a sensor protocol that tolerates occasional lost readings.
Study "IP addressing and routing" first (topic 67 of 104 in Software & Computing). It covers the groundwork this topic builds on.
Three-way handshake. Sliding window. Ports.
A file transfer uses TCP; a live video call uses UDP.
The next topic is "DNS", which builds directly on this one.
It is classed as Intermediate in Software & Computing (topic 68 of 104). It is an intermediate topic. Work through the beginner topics in Software & Computing first.
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