1# SPDX-License-Identifier: GPL-2.0-only 2# 3# CCITT X.25 Packet Layer 4# 5 6config X25 7 tristate "CCITT X.25 Packet Layer" 8 help 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). 19 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>. 23 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). 30 31 To compile this driver as a module, choose M here: the module 32 will be called x25. If unsure, say N. 33