Secure Shell (SSH) is a method of logging in to a remote computer to execute commands on that machine. SSH keys are used in key-based authentication system as an alternative to the default password authentication system. With key-based authentication, there is no need to manually type a password to authenticate.
Click Applications › Utilities › Passwords and Keys.
Click File › New.
Select Secure Shell Key, then click Continue.
Specify a description of what the key is to be used for.
You can use your e-mail address or any other reminder.
Optionally, click Advanced key options to specify the following advanced options for the key.
Encryption Type. Specifies the encryption algorithms used to generate your keys. Select RSA to use the Rivest-Shamir-Adleman (RSA) algorithm to create the SSH key. This is the preferred and more secure choice. Select DSA to use the Digital Signature Algorithm (DSA) to create the SSH key.
Key Strength. Specifies the length of the key in bits. The longer the key, the more secure it is (provided a strong passphrase is used). Keep in mind that performing any operation with a longer key requires more time than it does with a shorter key. Acceptable values are between 1024 and 4096 bits. At least 2048 bits is recommended.
Click Just Create Key to create the new key, or click Create and Set Up to create the key and set up another computer to use for authentication.
Specify the passphrase for your new key, click OK, then repeat.
When you specify a passphrase, use the same practices you use when you create a strong password.