Orion NetFlow Traffic Analyzer provides a new level of visibility into
  network traffic behavior and trends. By leveraging Cisco's NetFlow protocol
  to extract data from routers, NetFlow Traffic Analyzer provides an in-depth
  view into which users and applications are consuming the most bandwidth.
  
  NetFlow Traffic Analyzer converts that data into charts and tables
  providing network engineers with a easy way to identify and isolate the
  cause and source of network problems, as well as provide historical
  performance information to help plan for future growth. Pie charts show the
  distribution of bandwidth across different types of traffic (e.g., HTTP,
  FTP, VoIP) and across different users. Line charts show the usage patterns
  over time. NetFlow Traffic Analyzer can also identify the source of
  external traffic inbound to the corporate network.