Review the sample programs (whose source can be found in the Student sub-directory under my account in the lab: cd ~allisor/Student/cst8217) from the Sockets Introduction lecture.
What you are to do for Lab 9 is to create an "echo" program and a corresponding server, using the SOCK_STREAM protocol (TCP). This is an unusual use of sessions, but it will work just fine. You will develop and run these programs on your virtual network under VMware.
Your echo server will wait for an echo client to start a session, and will then return the single text message sent from the client, modified in some way that can easily be recognized. The echo client, which can be run repeatedly and even at the same time, will take the server IP address and a text argument from command-line arguments, send the text to the echo server, and display the resulting reply.
Now read over the instructions for Lab 9 and follow them carefully.