A paper key is a machine-readable print of a

cryptographic Cryptography, or cryptology (from grc, , translit=kryptós "hidden, secret"; and ''graphein'', "to write", or ''-logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adver ...

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

, 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 from ...

. or human-readable

base 16 In mathematics and computing, the hexadecimal (also base-16 or simply hex) numeral system is a positional numeral system that represents numbers using a radix (base) of 16. Unlike the decimal system representing numbers using 10 symbols, hexad ...

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 electronic photodetectors interfaced to an analog-to-digital converter (ADC) to produce images focused by a lens, as opposed to an exposure on photographic film. The digitized image i ...

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

See also

External links