[ns] How to program a node in the network

[priyadharshini Manoharan]

Dear friends

Do someone know how to insert a customized messages inside a node. By doing
so, the node act according to the conditions specified by us.For my project
i need to check the threshold values of the packets, if any packet's
threshold value exceeds the defaultly seted value then congestion occurs in
a particular route.If anybody related to this please do help me.

Thanks & Regards
Priyadharshini.M