[ndnSIM] Problem in Forwarding module

[Mortaza Nikzad]

Hi all
I run ndn-congestion-alt-topo-plugin.cpp example with --visualize option to see how ndn utilize links in congestion situation but seems the forwarding module do not work correctly and all of packets transmitted through congested link!!! I checked the trace file too.
has anyone an idea about this? 
I also tested it with a different topology and receive the same incorrect result.
my ndnSIM is clean and without any change. I installed it based on ndnSIM website instruction. 
any idea can be usefull.
thanks