5-minute Introduction To SSH Tunneling


SSH is basically a client-server based protocol for making server requests. SSH tunnelling, or SSH port forwarding, is a method of transporting arbitrary data over an encrypted SSH connection.


SSH uses port 22 by default to enable data encryption of payloads being transmitted over a public network (such as the Internet) connection, thereby providing VPN functionality.

SSH Vs SSH Tunnelling


The SSH connection is used by the application to connect to the application server. With tunnelling enabled, the application contacts a port on the local host that the SSH client listens on. The SSH client then forwards the application over its encrypted tunnel to the server.

SSH Vs VPN


The main difference between both technologies is that the SSH connects to a particular computer while a VPN connects to a network. Each of them provides an additional layer of security when browsing online.

Another key difference between VPN and SSH tunnelling is that VPN runs on the transport layer while SSH runs on the application layer of a network.

SSH Clients for Windows

Apart from Linux distros that come with SSH by default, I believe Windows 10 has a built-in SSH client that you can use in Windows Terminal which is an optional setting that you can actually toggle.

SSH Keys


Just like how web 3.0 wallets work, SSH keys also come in pairs, and every pair is made up of a private key and a public key.

The private key is secret, known only to the user, and should be encrypted and stored safely. The public key can be shared freely with any SSH server to which the user wishes to connect.

Use-Cases

SSH tunnelling is mostly used in scenarios when you need to connect to a remote computer behind the firewall.

  • Local TCP forwarding is a local port forwarding to a remote server.
  • Remote TCP forwarding is a remote port forwarding to a local computer.
  • Double SSH tunnel connects computers without any dedicated public IP addresses behind a NAT.
  • Transfer unencrypted traffic over a network through an encrypted channel.
  • You can create a basic VPN.

Windows Native SSH


If you are using Windows 10 and have enabled Windows Subsystem Bash and are running Ubuntu distro natively on your computer, you have the ability to SSH in without other tools by using OpenSSH

You can alternatively enable SSH if not enabled and can be started by typing ssh in the terminal.

Head over to https://blog.octachart.com/introduction-to-ssh-tunneling for the detailed verison.

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