The CERTSI (Security and Industry Computer Emergency Response Team), a public agency operated by INCIBE (Spanish Cybersecurity National Institute), has published in its website (08/03/2017) an interesting article highlighting all the benefits of redundant protocols like HSR/PRP in the design of the network to secure critical systems.
As explained in the document, these protocols optimize two very important vectors of Security: the Availability and the Integrity of the information.
More information: https://www.certsi.es/blog/prp-y-hsr-protocolos-redundantes