PasswordA password, sometimes called a passcode (for example in Apple devices), is secret data, typically a string of characters, usually used to confirm a user's identity. Traditionally, passwords were expected to be memorized, but the large number of password-protected services that a typical individual accesses can make memorization of unique passwords for each service impractical. Using the terminology of the NIST Digital Identity Guidelines, the secret is held by a party called the claimant while the party verifying the identity of the claimant is called the verifier.
Password strengthPassword strength is a measure of the effectiveness of a password against guessing or brute-force attacks. In its usual form, it estimates how many trials an attacker who does not have direct access to the password would need, on average, to guess it correctly. The strength of a password is a function of length, complexity, and unpredictability. Using strong passwords lowers the overall risk of a security breach, but strong passwords do not replace the need for other effective security controls.
Passwdpasswd is a command on Unix, Plan 9, Inferno, and most Unix-like operating systems used to change a user's password. The password entered by the user is run through a key derivation function to create a hashed version of the new password, which is saved. Only the hashed version is stored; the entered password is not saved for security reasons. When the user logs on, the password entered by the user during the log on process is run through the same key derivation function and the resulting hashed version is compared with the saved version.
Password crackingIn cryptanalysis and computer security, password cracking is the process of recovering passwords from data that has been stored in or transmitted by a computer system in scrambled form. A common approach (brute-force attack) is to repeatedly try guesses for the password and to check them against an available cryptographic hash of the password. Another type of approach is password spraying, which is often automated and occurs slowly over time in order to remain undetected, using a list of common passwords.
Password managerA password manager is a computer program that allows users to store and manage their passwords for local applications or online services such as web applications, online shops or social media. Password managers can generate passwords and fill online forms. Password managers may exist as a mix of: computer applications, mobile applications, or as web browser extensions. A password manager may assist in generating passwords, storing passwords, usually in an encrypted database.
Secure Remote Password protocolThe Secure Remote Password protocol (SRP) is an augmented password-authenticated key exchange (PAKE) protocol, specifically designed to work around existing patents. Like all PAKE protocols, an eavesdropper or man in the middle cannot obtain enough information to be able to brute-force guess a password or apply a dictionary attack without further interactions with the parties for each guess. Furthermore, being an augmented PAKE protocol, the server does not store password-equivalent data.
One-time passwordA one-time password (OTP), also known as a one-time PIN, one-time authorization code (OTAC) or dynamic password, is a password that is valid for only one login session or transaction, on a computer system or other digital device. OTPs avoid several shortcomings that are associated with traditional (static) password-based authentication; a number of implementations also incorporate two-factor authentication by ensuring that the one-time password requires access to something a person has (such as a small keyring fob device with the OTP calculator built into it, or a smartcard or specific cellphone) as well as something a person knows (such as a PIN).
SecuritySecurity is protection from, or resilience against, potential harm (or other unwanted coercion) caused by others, by restraining the freedom of others to act. Beneficiaries (technically referents) of security may be of persons and social groups, objects and institutions, ecosystems or any other entity or phenomenon vulnerable to unwanted change. Security mostly refers to protection from hostile forces, but it has a wide range of other senses: for example, as the absence of harm (e.g.
User interfaceIn the industrial design field of human–computer interaction, a user interface (UI) is the space where interactions between humans and machines occur. The goal of this interaction is to allow effective operation and control of the machine from the human end, while the machine simultaneously feeds back information that aids the operators' decision-making process. Examples of this broad concept of user interfaces include the interactive aspects of computer operating systems, hand tools, heavy machinery operator controls and process controls.
Secure ShellThe Secure Shell Protocol (SSH) is a cryptographic network protocol for operating network services securely over an unsecured network. Its most notable applications are remote login and command-line execution. SSH applications are based on a client–server architecture, connecting an SSH client instance with an SSH server. SSH operates as a layered protocol suite comprising three principal hierarchical components: the transport layer provides server authentication, confidentiality, and integrity; the user authentication protocol validates the user to the server; and the connection protocol multiplexes the encrypted tunnel into multiple logical communication channels.