Ok , Can ns3 3.19 update to 3.21? Or I need reinstall it?
>>yes it is possible to update, but you must patch you code first to ns-3.20, and then patch to ns-3.21.
>>You can also have multiple ns-3 installations on the same machine, i.e. ns-3.19 and 3.21.
Sorry, i don't know what ns-3-dev is.
>>ns-3-dev contains the latest changes. It is the most up-to-date version, but it is not a stable version and may contains some new bugs.
>>Please also note that the new ns-3.22 release is planned to be finalized this week.
By
the way, i want to know whether ns-3 supprot that one node install more
than one applications and every application gernerates packets to send
to different IP address.
>> It should be possible.