Being agent-less appliances, Network Performance Monitoring tools rest on the network inspecting content and traffic by catching packets flowing through the network. They understand the wire protocols across the application tiers and thereby measure response times and find errors in applications. Like agent based APM solutions, they automatically discover your application topology.
AppDynamics has the capability to discover and map application architecture and dependencies automatically. This gives you a clear picture of application performance even if your application is complex.
AppDynamics helps you to identify and fix an issue at the method and class level. With the tool, you can go down into an individual call stack and discover the causes for a slow Business Transaction.
With AppDynamics' proactive alerts, there wouldn't be any instances of alert storming or missed problems.
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