A keyfile is a file on a computer which contains encryption

Encryption

In cryptography, encryption is the process of transforming information using an algorithm to make it unreadable to anyone except those possessing special knowledge, usually referred to as a key. The result of the process is encrypted information...

 or license keys.

A common use is web server software running secure socket layer (SSL) protocols. Server-specific keys issued by trusted authorities are merged into the keyfile along with the trusted root certificates. By this method keys can be updated without recompiling software or rebooting the server.

A keyfile is often part of a public key infrastructure

Public key infrastructure

Public Key Infrastructure is a set of hardware, software, people, policies, and procedures needed to create, manage, distribute, use, store, and revoke digital certificates. In cryptography, a PKI is an arrangement that binds public keys with respective user identities by means of a certificate...

 (PKI).

Some applications use a keyfile to hold licensing information, which is periodically reviewed to ensure currency and compliance. Other applications allow users to merge multiple service-specific security settings into a single common store (for example, Apple Computer's Keychain in later Mac OS X

Mac OS X

Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...

 versions, GNOME Keyring

GNOME Keyring

GNOME Keyring is a daemon application designed to take care of the user's security credentials, such as user names and passwords. The sensitive data is encrypted and stored in a keyring file in the user's home folder...

 and KWallet

KWallet

KWallet is a credentials management application for the KDE Software Compilation desktop environment . It provides a centralized way for users to store sensitive passwords in encrypted files, called "wallets". For added security, each wallet can be used to store a different kind of credentials,...

 in the GNOME

GNOME

GNOME is a desktop environment and graphical user interface that runs on top of a computer operating system. It is composed entirely of free and open source software...

 and KDE

KDE

KDE is an international free software community producing an integrated set of cross-platform applications designed to run on Linux, FreeBSD, Microsoft Windows, Solaris and Mac OS X systems...

 environments in Linux

Linux

Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...

, respectively).

See also

• License manager
  License manager
  A license manager is a software management tool used by software vendors or by end-user organizations to control where and how software products are able to run. License managers protect software vendors from losses due to software piracy and enable end-user organizations to enforce compliance with...
  
  
• List of license managers
• Passphrase
  Passphrase
  A passphrase is a sequence of words or other text used to control access to a computer system, program or data. A passphrase is similar to a password in usage, but is generally longer for added security. Passphrases are often used to control both access to, and operation of, cryptographic programs...
  
  
• Encryption software
  Encryption software
  Encryption software is software whose main task is encryption and decryption of data, usually in the form of files on hard drives and removable media, email messages, or in the form of packets sent over computer networks.-Security:...
  
  
• Product activation
  Product activation
  Product activation is a license validation procedure required by some proprietary computer software programs. In one form, product activation refers to a method invented by Ric Richardson and patented by Uniloc where a software application hashes hardware serial numbers and an ID number specific...
  
  
• Digital rights management
  Digital rights management
  Digital rights management is a class of access control technologies that are used by hardware manufacturers, publishers, copyright holders and individuals with the intent to limit the use of digital content and devices after sale. DRM is any technology that inhibits uses of digital content that...