1# SPDX-License-Identifier: GPL-2.0-only
2#
3# IEC 62439-3 High-availability Seamless Redundancy
4#
5
6config HSR
7	tristate "High-availability Seamless Redundancy (HSR & PRP)"
8	help
9	  This enables IEC 62439 defined High-availability Seamless
10	  Redundancy (HSR) and Parallel Redundancy Protocol (PRP).
11
12	  If you say Y here, then your Linux box will be able to act as a
13	  DANH ("Doubly attached node implementing HSR") or DANP ("Doubly
14	  attached node implementing PRP"). For this to work, your Linux box
15	  needs (at least) two physical Ethernet interfaces.
16
17	  For DANH, it must be connected as a node in a ring network together
18	  with other HSR capable nodes. All Ethernet frames sent over the HSR
19	  device will be sent in both directions on the ring (over both slave
20	  ports), giving a redundant, instant fail-over network. Each HSR node
21	  in the ring acts like a bridge for HSR frames, but filters frames
22	  that have been forwarded earlier.
23
24	  For DANP, it must be connected as a node connecting to two
25	  separate networks over the two slave interfaces. Like HSR, Ethernet
26	  frames sent over the PRP device will be sent to both networks giving
27	  a redundant, instant fail-over network. Unlike HSR, PRP networks
28	  can have Singly Attached Nodes (SAN) such as PC, printer, bridges
29	  etc and will be able to communicate with DANP nodes.
30
31	  This code is a "best effort" to comply with the HSR standard as
32	  described in IEC 62439-3:2010 (HSRv0) and IEC 62439-3:2012 (HSRv1),
33	  and PRP standard described in IEC 62439-4:2012 (PRP), but no
34	  compliancy tests have been made. Use iproute2 to select the protocol
35	  you would like to use.
36
37	  You need to perform any and all necessary tests yourself before
38	  relying on this code in a safety critical system!
39
40	  If unsure, say N.
41