Provided is a method and system for monitoring and analysis of networked systems, that is non-intrusive and real time. Both secure and non-secure traffic may be analyzed. The provided method involves non-intrusively copying data from a communication medium, reconstructing this data to a higher level of communication, such as the application level, grouping the data into sets, each set representing a session, and organizing the data for chosen sessions in hierarchical fashion which corresponds to the hierarchy of the communicated information. If monitored communications are encrypted, they are non-intrusively decrypted in real time. Hierarchically reconstructed session data is used by one or more plug-in applications, such as alarms, archival applications, visualization applications, script generation applications, abandonment monitoring applications, error detection applications, performance monitoring applications, and others.