The VSR-NRC 1+1 redundancy features introduces a global channel between each VSR-NRC and the NRC-P for exchanging channel health and notification messages that are not application-specific.
Figure: Global health and notification channel message sequence illustrates the sequence of messages to establish the global health and notification channel as well as the sequence of messages used for establishing the VSR-NRC role of active or standby.
Figure: Global health and notification channel message sequence
