Populate User router or traffic control simulation.

[Yuan Zuo]

Hi, all

I understand there is a discussion about populate customized routing table at https://groups.google.com/forum/#!topic/ns-3-users/zFokAihpXoA 

However this is still unclear to me. Seems there does not exist API for user to modify routing protocal to simulate their own. 

Can anyone give me an example how to populate this. 

I know the short answer is to override "Ipv4RoutingProtocol", but this is still confusing based on other implementations like "Global Routing", or "Ipv4ListRouting", which contains tons of functions. 

From "Ipv4RoutingProtocol", it seems there are only several virtual functions. 

Cheers.