How are the individual applications monitored on per user basis in the overlay network?

Availability monitoring checks if an application is up or down, which is different from individual per-user performance metrics.

Bandwidth monitoring tracks data usage, which is a component of performance but not the overarching goal of monitoring applications per user.

Tunnel monitoring relates to the health of the underlying transport tunnels, not the performance of individual applications or users traversing those tunnels.

Monitoring individual applications on a per-user basis is primarily done to assess their 'performance', including metrics like latency, jitter, and packet loss, which are crucial for ensuring a quality user experience and identifying application-specific issues within the SD-WAN overlay.