Execution of the programs : PEM keys used in all these is 1234 For second program: ------------------- run it by using : Insert the root certificate into the browser sudo python q_2_form.py make a entry in /etc/hosts for server_cse with correspoding ip Then open browser and type https://server_cse For third program: ------------------- run it in two instances Instance 1: run the python file and give input a port <port1> <port2> 0 Instance 2: if you want the peer to be under same Intermediate CA: Run the python file and give input as <port2> <port1> 0 if you want the peer to be under different Intermediate CA but same root CA: Run the python file and give input as <port2> <port1> 1 once authenticated you can send messages For fourth program: -------------------- run it in two instances Instance 1: run the python file and give input a port <port1> <port2> 0 run it in two instances Instance 2: run the python file and give input a port <port2> <port1> 0 once authenticated you can send messages.