162306a36Sopenharmony_ci# SPDX-License-Identifier: GPL-2.0-only
262306a36Sopenharmony_ci#
362306a36Sopenharmony_ci# CCITT X.25 Packet Layer
462306a36Sopenharmony_ci#
562306a36Sopenharmony_ci
662306a36Sopenharmony_ciconfig X25
762306a36Sopenharmony_ci	tristate "CCITT X.25 Packet Layer"
862306a36Sopenharmony_ci	help
962306a36Sopenharmony_ci	  X.25 is a set of standardized network protocols, similar in scope to
1062306a36Sopenharmony_ci	  frame relay; the one physical line from your box to the X.25 network
1162306a36Sopenharmony_ci	  entry point can carry several logical point-to-point connections
1262306a36Sopenharmony_ci	  (called "virtual circuits") to other computers connected to the X.25
1362306a36Sopenharmony_ci	  network. Governments, banks, and other organizations tend to use it
1462306a36Sopenharmony_ci	  to connect to each other or to form Wide Area Networks (WANs). Many
1562306a36Sopenharmony_ci	  countries have public X.25 networks. X.25 consists of two
1662306a36Sopenharmony_ci	  protocols: the higher level Packet Layer Protocol (PLP) (say Y here
1762306a36Sopenharmony_ci	  if you want that) and the lower level data link layer protocol LAPB
1862306a36Sopenharmony_ci	  (say Y to "LAPB Data Link Driver" below if you want that).
1962306a36Sopenharmony_ci
2062306a36Sopenharmony_ci	  You can read more about X.25 at <https://www.sangoma.com/tutorials/x25/> and
2162306a36Sopenharmony_ci	  <http://docwiki.cisco.com/wiki/X.25>.
2262306a36Sopenharmony_ci	  Information about X.25 for Linux is contained in the files
2362306a36Sopenharmony_ci	  <file:Documentation/networking/x25.rst> and
2462306a36Sopenharmony_ci	  <file:Documentation/networking/x25-iface.rst>.
2562306a36Sopenharmony_ci
2662306a36Sopenharmony_ci	  One connects to an X.25 network either with a dedicated network card
2762306a36Sopenharmony_ci	  using the X.21 protocol (not yet supported by Linux) or one can do
2862306a36Sopenharmony_ci	  X.25 over a standard telephone line using an ordinary modem (say Y
2962306a36Sopenharmony_ci	  to "X.25 async driver" below) or over Ethernet using an ordinary
3062306a36Sopenharmony_ci	  Ethernet card and the LAPB over Ethernet (say Y to "LAPB Data Link
3162306a36Sopenharmony_ci	  Driver" and "LAPB over Ethernet driver" below).
3262306a36Sopenharmony_ci
3362306a36Sopenharmony_ci	  To compile this driver as a module, choose M here: the module
3462306a36Sopenharmony_ci	  will be called x25. If unsure, say N.
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