PIN Length
The concept of a PIN originates with the inventor of the ATM, John Shepherd-Barron. One day in 1967, while thinking about more efficient ways banks could dispense cash to their customers, it occurred to him that the vending machine model was a proven fit. For authentication Shepherd-Barron at first envisioned a six-digit numeric code, given what he could reliably remember. His wife however preferred four digits, which became the most commonly used length. ISO 9564-1, the international standard for PIN management and security, allows for PINs from four up to twelve digits, but also notes that "For usability reasons, an assigned numeric PIN should not exceed six digits in length."
Apart from financial uses, GSM mobile phones specify a PIN of between four and eight digits. The PIN is recorded in the SIM card.
Read more about this topic: Personal Identification Number
Famous quotes containing the words pin and/or length:
“A man is a beggar who only lives to the useful, and, however he may serve as a pin or rivet in the social machine, cannot be said to have arrived at self-possession.”
—Ralph Waldo Emerson (1803–1882)
“An ... important antidote to American democracy is American gerontocracy. The positions of eminence and authority in Congress are allotted in accordance with length of service, regardless of quality. Superficial observers have long criticized the United States for making a fetish of youth. This is unfair. Uniquely among modern organs of public and private administration, its national legislature rewards senility.”
—John Kenneth Galbraith (b. 1908)