TCP vs UDP

Posted Aug 15, 2026 · 0 views

The cut is simple: does anything come back?

TCP acknowledges every segment. A lost segment is noticed and re-sent, so nothing is missing — but the replacement arrives late, and everything behind it waits. Traffic is bidirectional and the rhythm is call-and-response.

UDP sends datagrams one way and nothing reacts. A lost one is simply gone: no acknowledgement, no retransmit, no waiting. The rhythm is a steady one-way stream with a hole in it.

Neither is the better protocol. A file transfer cannot tolerate the hole; a live call cannot tolerate the wait.