Flow Monitoring and Discard Accounting Overview

Using a Juniper Networks M-series or T-series routing platform, a selection of PICs (including the Monitoring Services PIC, Adaptive Services [AS] PIC, MultiServices PIC, or MultiServices DPC) 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 IP version 4 (IPv4) traffic flows between source and destination nodes in your network.
• Sample all incoming IPv4 traffic on the monitoring interface and present the data in cflowd record format.
• Perform discard accounting on an incoming traffic flow.
• Encrypt or tunnel outgoing cflowd records, intercepted IPv4 traffic, or both.
• Direct filtered traffic to different packet analyzers and present the data in its original format (port mirror).

  Note: Monitoring Services PICs, AS PICs, and MultiServices PICs must be mounted on an Enhanced Flexible PIC Concentrator (FPC) in an M-series or T-series routing platform. MultiServices DPCs installed in MX-series routing platforms support the same functionality, with the exception of the passive monitoring and flow-tap features.

This section provides general information on the following topics:

• Passive Flow Monitoring
• Active Flow Monitoring