#1
❇️ What is OTP token ? ❇️

A one-time password token (OTP token) is a security hardware device or software program that is capable of producing a single-use password or PIN passcode.

One-time password tokens are often used as a part of two-factor and multifactor authentication. The use of one-time password tokens hardens a traditional ID and password system by adding another, dynamic credential.

Depending upon the vendor, an OTP token will generate a PIN synchronously or asynchronously. Synchronous tokens use a secret key and time to create a one-time password. Asynchronous tokens use a challenge-response authentication mechanism (CRAM).

In the past, OTP security tokens were usually pocket-size fobs with a small screen that displayed a number. The number changed every 30 or 60 seconds, depending on how the token is configured and the user entered his or her user name and password, plus the number displayed on the token.

Today, OTP tokens are often software-based, and the passcode generated by the token is displayed on the user's smartphone screen. Software tokens make it easier for mobile users to enter authentication information and not have to keep track of a separate piece of hardware.


❇️ What is an image replay attack ? ❇️

An image replay attack is the use of a picture to fool an authentication method.

Image replay attacks are most commonly used by an attacker trying to gain entry to a system protected by less-than-secure biometric authentication technology implementations. The method has been used successfully against low-end fingerscanners, iris scanners and facial recognition systems.

In the simplest cases, image replay attacks involve a printed image of the subject used for authentication. An attacker might, for example, present a picture of an authorized user to a facial recognition system. Extra measures can be implemented in facial recognition and iris scans to foil printed or static images, however; such measures include requiring the user to wink, blink or speak.

More sophisticated image replay attack methods may involve recorded video and audio playback to defeat these measures. Methods of defeating these attacks exist as well, however. Video and audio are typically out of sync to a detectable degree when played back from a file. Security algorithms have been created to detect the discrepancy and prevent these attacks.

Making biometric authentication methods secure from image replay attacks can't rely on the methods used to detect data replay attacks. (The opposite is also true.) When security is important, it is advisable for administrators to be aware of both attack methods and counter measures.

FOR EDUCATIONAL AND INFORMATIONAL PURPOSES ONLY. The information provided in or through this website is for educational and informational purposes only and solely as a self-help tool for your own use.