Personal identification number

From Wikipedia, the free encyclopedia

(Redirected from Pin number)
Jump to: navigation, search

A personal identification number (PIN) is a secret numeric password shared between a user and a system that can be used to authenticate the user to the system. Typically, the user is required to provide a non-confidential user identifier or token (such as a banking card) and a confidential PIN to gain access to the system. Upon receiving the User ID and PIN, the system looks up the PIN based upon the User ID and compares the looked-up PIN with the received PIN. The user is granted access only when the number entered matches with the number stored in the system.

PINs are most often used for ATMs but are increasingly used at the Point of sale, especially for debit cards. Throughout Europe the traditional in-store credit card signing process is being replaced with a system where the customer is asked to enter their PIN instead of signing. In the UK and Ireland this goes under the term 'Chip and PIN', since PINs were introduced at the same time as EMV chips on the cards. In other parts of the world, PINs have been used before the introduction of EMV. Apart from financial uses, GSM mobile phones usually allow the user to enter PIN between 4 and 8 digits length. The PIN is recorded in the SIM card.

In 2006, James Goodfellow, the inventor of the personal identification number, was awarded an OBE in the Queen's Birthday Honours List.[1]

Contents

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 disburse cash to their customers, it occurred to him that the candy 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 standard. [2]

Financial PINs are often 4-digit numbers in the range 0000-9999, resulting in 10,000 possible numbers. Many PIN verification systems allow three attempts, thereby giving a card thief a 1/3333 chance to guess the correct PIN before the card is blocked. This holds only if all PINs are equally likely and the attacker has no further information available, which has not been the case with some of the many PIN generation and verification algorithms that banks and ATM manufacturers have used in the past.[3]

If a mobile phone PIN is entered incorrectly three times, the SIM card is blocked until a Personal Unblocking Code (PUC), provided by the service operator, is entered. If the PUC is entered incorrectly ten times, the SIM card is permanently blocked, requiring a new SIM card.

In 2002 two PhD students at Cambridge University, Piotr Zieliński and Mike Bond, discovered a security flaw in the PIN generation system of the IBM 3624, which was duplicated in most later hardware. Known as the decimalization table attack, the flaw would allow someone who has access to a bank's computer system to determine the PIN for an ATM card in an average of 15 guesses.[4][5]

In 2006 two researchers Omer Berkman and Odelia Moshe Ostrovsky, discovered several security flaws in the PIN processing standards. Published under the title The Unbearable Lightness of PIN Cracking, the flaw would allow someone who has access to a bank's computer system to determine the PIN for an ATM card in as little as one guess, and to attack bank customers of other banks.[6]

The term "PIN number" (hence "personal identification number number") is commonly used, which is an example of RAS syndrome (Redundant Acronym Syndrome).

Rumours have been in e-mail circulation claiming that in the event of entering a PIN into an ATM backwards, police will be instantly alerted as well as money being ordinarily issued as if the PIN had been entered correctly.[7] The intention of this scheme would be to protect victims of muggings; however, despite the system being proposed for use in some American states, there are no ATMs currently in existence that employ the software.

  1. ^ Royal honour for inventor of Pin. BBC (2006). Retrieved on 2007-11-05.
  2. ^ The Man Who Invented The ATM Machine. BBC (2007). Retrieved on 2007-03-02.
  3. ^ Kuhn, Markus (July 1997). "Probability theory for pickpockets — ec-PIN guessing" (PDF). Retrieved on 2006-11-24.
  4. ^ Zieliński, P & Bond, M (February 2003). "Decimalisation table attacks for PIN cracking" (PDF). University of Cambridge Computer Laboratory. Retrieved on 2006-11-24.
  5. ^ Media coverage. University of Cambridge Computer Laboratory. Retrieved on 2006-11-24.
  6. ^ Berkman, O & Ostrovsky, O (November 2006). "The Unbearable Lightness of PIN Cracking" (PDF). Retrieved on 2006-11-24.
  7. ^ Reverse PIN Panic Code. Retrieved on 2007-03-02.
Advanced Search
Included Web Search Engines


Safe Search

close

Top Matching Results

Occasionally Search.com will highlight specialized results that are based on the context of your query. Examples of specialized results include specific links to news, images, or video.

Top Matching Results may highlight information from other Search.com pages, content from the CNET Network of sites, or third party content. The listings are based purely on relevance. Search.com does not receive payment for listings in this section but our partners that provide this data may get paid for listing these products.

Sponsored Links

This section contains paid listings which have been purchased by companies that want to have their sites appear for specific search terms and related content. These listings are administered, sorted and maintained by a third party and are not endorsed by Search.com.

Search Results

Search.com sends your search query to several search engines at one time and integrates the results into one list which has been sorted by relevance using Search.com's proprietary algorithm. You can customize the list of search engines included in your metasearch from the preferences.

The search engines that are used in your metasearch may allow companies to pay to have their Web sites included within the results. To view the Paid Inclusion policy for a specific search engine, please visit their Web site. Search.com does not accept payment or share revenue with any search engine partner for listings in this section.