sir

you may use EXATA. i think it is very good tool but it is costiler.

Qualnet,Golosim

OMNet++ is a very good tool. good IDE. Its free has got great resources and community help docs.

OPNET is also good but its not free.

Personnally, I used NS2 to simulate IEEE 802.15.4 WSNs.

I suggest omnetpp. it is easy work with it.

all OSI layers can be found in it

Best regards

I haved used NS2

NS-3 is much better than the NS-2.

There are lot of university tools are available for research. Instead of using commercial tools like OPNET i suggest to use those tools

Had a model in C++/Cygwin & Matlab. Some hav used Simulink. In my experience, Matlab model was very easy to use where else C++/Cygwin model was faster. With Matlab model, could use much metrics as had the time to think than playing with code mismatches in C++.open source versions.

QualNet is an alternate option

Qualnet, OMNet++

sir i have work with NS-2 when i was working for WSN during master degree course, I think NS-2 is well organised for WSN protocol simulation. 

NS2 with mannasim is one of the best tools used in academia, for research purpose

ns3 or OMNet++

NS2 is the best tool.

Thanks

I feel NetSim is the best tool for WSN & MANET since it comes with source code and their is excellent technical support 

www.tetcos.com