How do secure communication systems protect data while it travels across public networks?
I keep reading that data sent over the internet can be exposed if it is not properly protected, which is why secure communication systems are used. But what I do not fully understand is how data remains safe while it is traveling through a public network that is used by millions of people at the same time. Is encryption the only protection method, or are there multiple layers involved such as authentication, verification, and traffic isolation? It feels like there must be a combination of technologies working together rather than just one simple method, especially when like tunnil net offer VPN and tunneling services to enhance privacy and security.
Also, how does the system ensure that the data is not modified or corrupted during transfer? And if someone tries to intercept it, what exactly prevents them from understanding or altering the information?