Re: [RFC PATCH net-next 10/12] Documentation: networking: dsa: add paragraph for the HSR/PRP offload

On Wed, Feb 24, 2021 at 7:42 PM Andrew Lunn [off-list ref] wrote:

quoted

+IEC 62439-3 (HSR/PRP)
+---------------------
+
+The Parallel Redundancy Protocol (PRP) is a network redundancy protocol which
+works by duplicating and sequence numbering packets through two independent L2
+networks (which are unaware of the PRP tail tags carried in the packets), and
+eliminating the duplicates at the receiver. The High-availability Seamless
+Redundancy (HSR) protocol is similar in concept, except all nodes that carry
+the redundant traffic are aware of the fact that it is HSR-tagged (because HSR
+uses a header with an EtherType of 0x892f) and are physically connected in a
+ring topology. Both HSR and PRP use supervision frames for monitoring the

I don't know HSR/PRP terms. Should it be supervisory instead of
supervision?

IEC 62439-3 refers to them primarily as supervision frames however
supervisory frames also appears once in the document.

quoted

+health of the network and for discovering the other nodes.

Either "discovering other nodes" or "discovery of other nodes".

quoted

+
+In Linux, both HSR and PRP are implemented in the hsr driver, which
+instantiates a virtual, stackable network interface with two member ports.
+The driver only implements the basic roles of DANH (Doubly Attached Node
+implementing HSR) and DANP (Doubly Attached Node implementing PRP); the roles
+of RedBox and QuadBox aren't (therefore, bridging a hsr network interface with

In colloquial English, you can get away with just 'aren't'. But in
Queens English, you should follow it with something, in this case
'supported'.

        Andrew