Network Tunneling - why do we need it? I have researched the topic of Network Tunnel but the information on this is rather confusing and inconsistent. So could someone please explain: 1. In general, What is tunneling? Is it simply an act of encapsulating a packet with another header and destine it to another point? 2. What is the purpose of tunneling? A switching or routing network is capable of delivering traffics, why then would you need a tunnel? What is the advantage?

The non technical explanation of the reason we like to use them "or need them" is not only encryption but within that tunnel we can supply routes to your computer or remote site that are private networks through the tunnel. This allows Site A to not only connect to Site B but I can have routes to other internal networks at Site A from Site B over a public circuit like the internet.

Examples, with normal communication I can connect to a remote ip address but not access all the internal private ip addresses because the internet doesn't support those addresses of course.

If I put a tunnel between two sites I can access networks like 192.168.1.0 for example even though it's in a diffrent location. It's almost like combining Lans.