This is my topology. It's a testbed so there is no connection to other networks.
Configuration of both routers and the ouput of my traceroute are attached.
I'm quite new to JUNOS so if there is something to say, do not hesitate.
Thank you again!
EDIT: I've done my tests using Layer-3 and Layer-4 at the same time and from the other computer as well. The output is the same.