User Datagram Protocol (UDP)

The ["UDP"] layer provides datagram based connectionless transport layer (layer 4) functionality in the InternetProtocolFamily.

UDP is only a thin layer and provides not much more than the described UDP port multiplexing.

Just like ["IP"], UDP also doesn't provide any mechanism to detect PacketLoss, DuplicatePackets and alike.

There are a lot of protocols on top of UDP, including: ["BOOTP"], ["DNS"], ["NTP"], ["SNMP"], ...


XXX - add a brief description of UDP history

Protocol dependencies

Example traffic

XXX - Add example traffic here (as plain text or Ethereal screenshot).


The UDP dissector is fully functional.

There are two statistical menu items for UDP available: Statistics/Endpoints which contains a tab showing all UDP endpoints (combination of IP address and UDP port) and Statistics/Conversations, which contains a tab showing all UDP conversations (combination of two endpoints).

Preference Settings

(XXX add links to preference settings affecting how UDP is dissected).

Example capture file

XXX - Add a simple example capture file. Keep it short, it's also a good idea to gzip it to make it even smaller, as Ethereal can open gzipped files automatically.

Display Filter

A complete list of UDP display filter fields can be found in the [ display filter reference]

Capture Filter