How VPN works internally [closed]

Question

The VPN is used to establish a secure connection (creating a tunnel) to another network over the Internet. It masks our IP address and geographical location and also when the information enters the private tunnel on a VPN, it is always encrypted before it is sent across on other networks.

This private tunnel on VPN allows us to access the data securely How it happens? and when we send an HTTPS request then the request is encrypted so there is no need for data encryption in that case, do we need a VPN to hide our IP address? is it the only usage( Hiding IP address) of VPN with HTTPS requests?

The understanding of the VPN is like an abstract view for me can anyone explain VPN clearly?

1. How it hides our IP address
2. How it creates the private channel on the internet
3. How the encryption happens

Answer 1

How it creates the private channel on the internet

It creates a connection between the VPN entry (usually directly on the client) and the VPN exit and then encapsulates all traffic into this connection. Imagine a train which transports passengers between two stations instead of the passengers walking this way by themselves.

The "private" comes from encryption so that nobody can see what is inside. Imagine the same train having no windows, so that nobody can look inside who is riding the train.

How it hides our IP address

It does not explicitly hide it. Using the analogy with the train again: the receiver has a limited view and can only see where the passengers exit the train (VPN exit) but not where they started their journey (VPN entry).

How the encryption happens

The details on how encryption works are really a topic by its own, especially if encryption is used which cannot easily broken. Try wikipedia:Encryption for an overview about the topic.

But essentially it is some (often publicly known) algorithm which has a secret key and which uses this key to somehow change (encrypt) the input. The output then gets later put into another matching algorithm with the same key (symmetric encryption) or a matching key (asymmetric encryption) to decrypt the data again. The goal is to make decryption possible only if the secret is known and not otherwise.