In the Cluster Communication Architecture Employed by an NS500 Clustered

In the cluster communication architecture employed by an NS500 clustered NAS system, modules such as the resource agent, HAD, GAB, and Low Latency Transport (LLT) must collaborate to implement cluster communication. Which of the following statements about the work mechanisms of these modules are correct? (Select three)

A) The agent monitors the resources of each system and provides the status information for the HAD of each machine.
B) If a cluster node is abnormal or faulty, the HAD takes correct actions, for example, performing a failover.
C) The GAB implements a point-to-point communication mechanism. The master node sends the other cluster nodes the information that needs to be synchronized.
D) LLT is a MAC-layer protocol unrelated to IP layer.