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A system for artificially dissipating fog, in which gasoline or other fuel is burned at intervals along an airstrip to be cleared. Derived from fog investigation dispersal operations.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


FInite DOmains. A constraint language implemented on top of Prolog.
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(1) For email, see FidoNet.

(2) (Fast IDentity Online) A technology from the FIDO Alliance that authenticates a user logging into an online service. In 2014, the Alliance introduced biometric and two-factor authentication methods.

Client and Server Interaction
When a user opens an account with an online service, the FIDO client in the user's app or browser registers with the FIDO counterpart in the provider's server. The FIDO client is used to select the authentication method (biometric or second factor), enroll the user and generate a private/public key pair. It keeps the private key in the user's device and sends the public key to the FIDO server. See public key cryptography.

When logging in, the FIDO client performs the biometric or second factor verification and then receives a challenge from the server. The client digitally signs the challenge, which the server verifies using the public key stored in the user's account. See digital signature.

FIDO UAF (Universal Authentication Framework)
The UAF is the biometric authentication protocol used by the FIDO client.

FIDO U2F (Universal Second Factor)
The U2F supports a second authentication device such as a USB security key or PIN. See two-factor authentication.

FIDO2 is the latest generation. FIDO2 uses the W3C's Web Authentication specification (WebAuthn), built into major browsers such as Chrome and Edge, and FIDO's client-to-authentication protocol (CTAP), which enables smartphones and USB security keys to work as FIDO authenticators.

A FIDO-Certified USB Key
This YubiKey FIPS is certified for FIDO second-factor authentication, and it meets federal standards (see FIPS 140-2). (Image courtesy of Yubico,
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References in periodicals archive ?
The other day an Alsatian ran across the fields and bit Fido on the leg.
He added that Apple iPhone 5S fingerprint sensor, Touch ID is in fact non-compliant with FIDO standards.
Nancy (later Mrs Hall) kept Fido until she was almost 90 years old, when she gave him to the Maritime Museum.
"We're not satisfied with this outcome for someone who knowingly caused this animal to suffer and die," Darcie Kurtz with FIDO told ( local news outlet RTV6 .
Fido Alliance is a consortium of more than 250 companies that create security standards.
Since then, Microsoft has been updating its implementationas it worked with other vendors and the FIDO alliance to develop the standard.
FIDO 2.0 is an open standard-based, user authentication framework that replaces passwords with advanced FIDO credentials that are designed to more effectively resist and fight off cyberattacks, including phishing and data breach attacks.
Dubbed Web Authentication or WebAuthn, this new open standard for web authentication relies on biometrics (fingerprints, facial recognition) and USB tokens to secure users' multiple web accounts, according to a statement from the Fast IDentity Online (FIDO) Alliance.
Authentication platform provider Nok Nok Labs, a founder of FIDO (Fast IDentity Online) Alliance, has announced that Japan-based Mizuho Bank has deployed Fujitsu Limited's FIDO-enabled Finplex online authentication service to provide improved authentication to mobile bank customers, the company said.
The Fetch Foundation, a nonprofit charity dedicated to saving pets, has donated "Fido Bags" to the Bartlett Fire Protection District this holiday season.
You may be tempted to spoil your new pet right off the bat with primo food, but do not switch away from the food he was fed at the shelter too soon, or Fido's upset stomach will lead to problems all over the rug you did not move.