By Steven Marlin, InformationWeek

Banks are in the midst of upgrading or replacing their automated teller machines to comply with new industry and government standards. Visa U.S.A. and MasterCard International have mandated that by April 1, 2005, all ATMs must be equipped to handle triple-DES (Data Encryption Standard), a method of scrambling personal identification numbers.
Banks for years have employed single-DES encryption, which specifies a key length of 56 bits; the triple-DES method uses a key length of 168 bits, making it more difficult for a hacker to crack personal identification numbers

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