ISDN user-network interface layer 3 specification for basic call control (Q.931)


XXX - add a brief description of Q.931 history

Protocol dependencies

Q.931 was originally used as the call control protocol for ISDN. It is also used for VoIP; when used for VoIP, it's usually transported atop TPKT atop TCP.

Example traffic

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


The Q.931 dissector is fully functional.

Preference Settings

Example capture file

XXX - Add a simple example capture file to the SampleCaptures page and link from here. Keep it short, it's also a good idea to gzip it to make it even smaller, as Wireshark can open gzipped files automatically.

Display Filter

A complete list of Q.931 display filter fields can be found in the display filter reference

Show only the Q.931 based traffic:


Capture Filter

You cannot directly filter Q.931 protocols while capturing. However, if you know the TCP port used (see above), you can filter on that one.

External links


Imported from https://wiki.wireshark.org/Q.931 on 2020-08-11 23:23:44 UTC