For SPAN/RSPAN/ERSPAN/NETFLOW and some similar traffic analysis and graphical represntation of such data is done using using Cisco' Hardware/Software - Network Analysis Module, aka, NAM.
However for SPAN/RSPAN and other feature you need to be selective on which NAM would suite you. You can check NAM Deployment guide to explore different NAM options.
For more details you can check :
http://www.cisco.com/en/US/products/ps5740/Products_Sub_Category_Home.html
NAM Deployment Guide:
http://www.cisco.com/en/US/prod/collateral/modules/ps2706/white_paper_c07-505273.html
-Thanks
Vinod
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