Differences between revisions 5 and 6
Revision 5 as of 2004-10-07 21:06:13
Size: 1861
Editor: GuyHarris
Comment: "it's" -> "its" when it's the possessive of "it". Tweak protocol ID stuff.
Revision 6 as of 2004-10-07 21:29:19
Size: 1863
Editor: GuyHarris
Comment: The IANA speaks of "assigned protocol numbers".
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 * ["IP"]: Typically, UDP uses ["IP"] as its underlying protocol. The well-known protocol ID for UDP on IP is 17.  * ["IP"]: Typically, UDP uses ["IP"] as its underlying protocol. The assigned protocol number for UDP on IP is 17.

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"], ...

History

XXX - add a brief description of UDP history

Protocol dependencies

  • ["IP"]: Typically, UDP uses ["IP"] as its underlying protocol. The assigned protocol number for UDP on IP is 17.

Example traffic

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

Ethereal

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 [http://www.ethereal.com/docs/dfref/u/udp.html display filter reference]

  • Show only the UDP based traffic:

     udp 

Capture Filter

  • Capture only the UDP based traffic:

     udp 

Discussion

User_Datagram_Protocol (last edited 2011-07-24 15:08:04 by LorenKellogg)