1 # SPDX-License-Identifier: GPL-2.0-only
3 # CCITT X.25 Packet Layer
7 tristate "CCITT X.25 Packet Layer"
9 X.25 is a set of standardized network protocols, similar in scope to
10 frame relay; the one physical line from your box to the X.25 network
11 entry point can carry several logical point-to-point connections
12 (called "virtual circuits") to other computers connected to the X.25
13 network. Governments, banks, and other organizations tend to use it
14 to connect to each other or to form Wide Area Networks (WANs). Many
15 countries have public X.25 networks. X.25 consists of two
16 protocols: the higher level Packet Layer Protocol (PLP) (say Y here
17 if you want that) and the lower level data link layer protocol LAPB
18 (say Y to "LAPB Data Link Driver" below if you want that).
20 Information about X.25 for Linux is contained in the files
21 <file:Documentation/networking/x25.rst> and
22 <file:Documentation/networking/x25-iface.rst>.
24 One connects to an X.25 network either with a dedicated network card
25 using the X.21 protocol (not yet supported by Linux) or one can do
26 X.25 over a standard telephone line using an ordinary modem (say Y
27 to "X.25 async driver" below) or over Ethernet using an ordinary
28 Ethernet card and the LAPB over Ethernet (say Y to "LAPB Data Link
29 Driver" and "LAPB over Ethernet driver" below).
31 To compile this driver as a module, choose M here: the module
32 will be called x25. If unsure, say N.