Managed to install NS. Looks like works OK, but when running the test-suite.tcl all the time get an Xgraph related message "Problems found with inputa data". Is there any requirement to the xgraph version? May be some other tips? Thanks Yuri PS: By the way had some problems with the compilation of rng.cc. Commented out the line 53, gettimeofday declaration. After that everything went OK.