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Flow Monitoring Overview


The flow monitoring application performs traffic flow monitoring and enables lawful interception of packets transiting between two routers. Traffic flows can either be passively monitored by an offline router or actively monitored by a router participating in the network.

Using a Juniper Networks router, a selection of PICs for M Series and T Series routers—including the Monitoring Services PIC, Monitoring Services II PIC, Adaptive Services PIC, and MultiServices PICs—and other networking hardware, you can monitor traffic flow and export the monitored traffic. Monitoring traffic allows you to do the following:

  • Gather and export detailed information about traffic flows between source and destination routers in your network.

  • Sample all incoming traffic on the monitoring interface and present the data in record format.

  • Encrypt or tunnel outgoing records, intercepted traffic, or both.

  • Direct filtered traffic to different packet analyzers and present the data in its original format.

  • Intercept unwanted traffic, discard it, and perform accounting on the discarded packets.

There are two main types of flow monitoring:

  • Active Flow Monitoring

  • Passive Flow Monitoring