Regarding VPNs and web security, one often hears about tunneling. What is it, and why is it used?
The following is by my understanding.
In broad strokes, a protocol is a way data is sent and received. The sender and receiver need to agree on a protocol before data exchange starts, so each can package the data the way it needs to be sent, then unpack what’s received, etc. The http protocols are examples (see my post from June 22 about that.)
On the Internet, information is sent in packets, typically large enough to contain only 500 to 1000 characters. Therefore, typical communication depends on sending many packets back and forth. The server and browser organize the packets; the user needn’t know about them.
Let’s imagine that a server and client want to exchange information using a private protocol, one that servers and browsers don’t understand. The motivation may be for security, for instance: if someone intercepts the communication, they won’t know how to decode it or rebuild it. Therefore, a hacker can’t derive meaning from the communication.
Yet, said information still needs to be broken down, prepped for transport over the Internet, received by the client’s browser, etc. This is accomplished by enveloping the packets from the private protocol in an outer protocol that is standard.
There are agreed-upon, secure protocols that can act as the “private” ones in the above example. Said protocols generally offer encryption besides what the outer protocol might offer.
Source:
cloudflare.com: What is tunneling?
cloudflare.com: What is a protocol?
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