if you want that) and the lower level data link layer protocol LAPB
(say Y to "LAPB Data Link Driver" below if you want that).
- You can read more about X.25 at <https://www.sangoma.com/tutorials/x25/> and
- <http://docwiki.cisco.com/wiki/X.25>.
Information about X.25 for Linux is contained in the files
<file:Documentation/networking/x25.rst> and
<file:Documentation/networking/x25-iface.rst>.