A paper key is a

machine-readable In communications and computing, a machine-readable medium (or computer-readable medium) is a medium capable of storing data in a format easily readable by a digital computer or a sensor. It contrasts with ''human-readable'' medium and data. T ...

print of a

cryptographic Cryptography, or cryptology (from "hidden, secret"; and ''graphein'', "to write", or '' -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adversarial behavior. More gen ...

key. The printed key can be used to decrypt data, e.g. archives or

backup In information technology, a backup, or data backup is a copy of computer data taken and stored elsewhere so that it may be used to restore the original after a data loss event. The verb form, referring to the process of doing so, is "wikt:back ...

data. A paper key can be the result of an offline private key protocol. The offline private key can also function as a token in

two-factor authentication Multi-factor authentication (MFA; two-factor authentication, or 2FA) is an electronic authentication method in which a user is granted access to a website or Application software, application only after successfully presenting two or more distin ...

. The idea is that a digital key to decrypt and recover sensitive or personal data should have long-term durability and not be stored on any computer or network. The length of secure cryptographic keys restricts memorization, so the secret key takes the form of a 2D

barcode A barcode or bar code is a method of representing data in a visual, Machine-readable data, machine-readable form. Initially, barcodes represented data by varying the widths, spacings and sizes of parallel lines. These barcodes, now commonly ref ...

, a machine-readable print. Early implementations of a paper key by the company Safeberg use a

Data Matrix A Data Matrix is a two-dimensional code consisting of black and white "cells" or dots arranged in either a square or rectangular pattern, also known as a matrix. The information to be encoded can be text or numeric data. Usual data size is fro ...

. or human-readable

base 16 Hexadecimal (also known as base-16 or simply hex) is a positional numeral system that represents numbers using a radix (base) of sixteen. Unlike the decimal system representing numbers using ten symbols, hexadecimal uses sixteen distinct symbols ...

digits."Paperkey - an OpenPGP key archiver"
by David Shaw The user stores the printed key in a secure location. To avoid abuse, the key can only be used in combination with a ‘normal’ password. The user can extract the key by creating a

digital photo Digital photography uses cameras containing arrays of electronics, electronic photodetectors interfaced to an analog-to-digital converter (ADC) to produce images focused by a lens (optics), lens, as opposed to an exposure on photographic film. ...

or scan of their paper key and feeding it to cryptographic software that extracts the key to decrypt the data.

External links

{{DEFAULTSORT:Trusted Paper Key Key management Data security Paper data storage

See also

External links