Thanks for your guides and helps Jaap and Anders.
Jaap,
a) What could be " protocol on top of TCP"? could you please tel me some examples? could MPEG-Dash be an instance? The application that i am using is MMT protocol.
b) In the sender side, MMT checks the length of each sample and it has to be at most equal to MTU ( which sets with user) if it is more than that value, then it divides to several fragments each one at most equal to MTU size . Is it different of what you tell about message boundary at sender side?
At receiver, MMT is receiving data with size of recv buffer (in socket programming) and i believe it is not "message boundary information" that you are talking about.
c) What do you suggest to me? changing MMT and adding this boundary? or adding another protocol beside MMT and TCP?
Thanks a lot for your time and guides.