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SESK: Stuff Everyone Should Know · sesk.info/aplus-udp-delivery

Which protocol, defined in RFC 768, does not guarantee delivery of its datagrams?

UDP (User Datagram Protocol) does not guarantee delivery.

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  1. UDP ✔
  2. TCP
  3. HTTPS

Why: RFC 768 says UDP is transaction oriented and delivery and duplicate protection are not guaranteed. That makes it light and fast, so it suits things like live voice and DNS lookups.

Huh, didn't know that: RFC 768, which defines UDP, is dated 28 August 1980.

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References

Answer: UDP. RFC 768 says UDP is transaction oriented and delivery and duplicate protection are not guaranteed. That makes it light and fast, so it suits things like live voice and DNS lookups.

  1. RFC 768: User Datagram Protocol www.rfc-editor.org/rfc/rfc768
    The protocol is transaction oriented, and delivery and duplicate protection are not guaranteed.
    Checked 2026-10-10.

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