What projects can I build around network security during an MCA?

Network security focuses on protecting systems and traffic from unauthorised access and attacks. Students should understand concepts such as authentication, firewalls, secure protocols and threat awareness. For an MCA learner, the best way to understand network security is to connect the theory with a small working example. This point is specifically relevant to the network security aspect of MCA study. For this specific question about network security, the practical takeaway is to relate the concept to your own MCA learning goal. In other words, this guidance addresses: What projects can I build around network security during an MCA?