Bala Shanmuga Priyan schrieb:

You can implement your own transport protocol by utilizing UDP .. UDP
gives you basically the Network layer and has nearly no data on
Transportlayer. Forming your own packets directly may not be allowed
based on what OS and what userrights you have, so there is no
implementation in java.

If you don't want to layer over UDP (as Christian has already suggested) then
you should be able to do it using a Java wrapper for the pcap library (pcaplib
or WinPcap).

I don't know whether pcap has Java wrappings available yet for sending packets
yet.  I not then you'd have to write your own -- but in comparison to
designing, implementing, and testing, a transport-layer protocol, that should
be a doddle ;-)

   -- chris

Java does not support raw sockets so you would need
to do something in C++ and use JNI.

Maybe look at http://www.savarese.org/software/rocksaw/ !

If it is for a real world problem: forget it and
focus on the higher level problems.

Arne