Description: An SSH key is a secure access credential used in the SSH (Secure Shell) protocol, which allows secure communication between a client and a server. This type of key consists of a pair of cryptographic keys: a public key and a private key. The public key can be shared freely and is stored on the server, while the private key is kept secret on the user’s device. This authentication system is more secure than traditional passwords, as keys are much harder to crack. Additionally, SSH keys allow authentication without the need to send passwords over the network, reducing the risk of man-in-the-middle attacks. SSH keys are widely used in various operating systems and environments where remote server management is common. Their implementation is essential for ensuring security in system administration and in the transfer of sensitive data, becoming a fundamental tool for system administrators and developers looking to protect their work environments.
History: The SSH protocol was created in 1995 by Tatu Ylönen, a Finnish security researcher, in response to the need for a secure method to access remote systems. The first version, SSH-1, introduced the concept of cryptographic keys for authentication. In 1996, SSH-2 was released, which improved security and functionality, including the use of public and private keys. Since then, SSH has become a standard in system administration and secure data transfer.
Uses: SSH keys are primarily used for authentication in remote connections to servers, allowing system administrators and developers to securely access their environments. They are also used in task automation, such as deploying scripts that require access to servers without manual intervention. Additionally, they are essential in configuring version control tools like Git, where a secure connection is required to interact with remote repositories.
Examples: A practical example of using SSH keys is connecting to a remote server using the command ‘ssh user@server’, where the user authenticates using their private key. Another example is configuring a Git repository on platforms like GitHub, where the public key can be added to the user’s profile to allow secure access to repositories without needing to enter a password each time.
