How to create a public key?

You can create a public key primarily by generating an SSH key pair using the ssh-keygen command-line utility. This generates both a private key (which you keep secret) and a public key (which you can share).

Generating an SSH Key Pair

The most common method for creating a public key is through generating an SSH (Secure Shell) key pair. Here's a breakdown of the process:

1. Using ssh-keygen: The core tool for generating SSH key pairs is the ssh-keygen command-line utility.

   • Open your terminal or command prompt.

   • Type the following command:

     ssh-keygen

   • Follow the prompts. You will be asked:

     • Where to save the key (the default is usually ~/.ssh/id_rsa).
     • To enter a passphrase (it's highly recommended to use a strong passphrase to protect your private key). You can leave it empty, but that is less secure.

2. Key Pair Location: By default, the ssh-keygen command creates two files in the ~/.ssh/ directory (on Unix-like systems) or a similar location on Windows if you have SSH utilities installed.

   • Private Key: id_rsa (or the filename you specified). Keep this file secret and secure. This is your identity.
   • Public Key: id_rsa.pub (or the filename you specified with the .pub extension). You can share this key.

3. Accessing the Public Key: The id_rsa.pub file contains your public key. You can open this file with a text editor to copy its contents. The public key usually starts with ssh-rsa, ssh-dss, ecdsa-sha2-nistp256, or ed25519, followed by a long string of characters, and ends with your username and hostname.

Important Considerations

• Security: Never share your private key. Anyone with your private key can impersonate you.
• Windows: If you are using Windows and don't have access to ssh-keygen, you may need to install an SSH client like Git for Windows, which includes the OpenSSH suite of tools.