Browse Prior Art Database

Secure Key Entry Apparatus

IP.com Disclosure Number: IPCOM000089100D
Original Publication Date: 1977-Sep-01
Included in the Prior Art Database: 2005-Mar-04
Document File: 4 page(s) / 96K

Publishing Venue

IBM

Related People

Ecker, ME: AUTHOR

Abstract

Key entry devices are currently employed in 24-hour bank terminals. These terminals permit bank customers to perform a number of bank transactions any time of the day without the presence of bank personnel. Basically, two conditions must be satisfied in order to activate these terminals, a coded credit card and a personal unique multidigit number.

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Secure Key Entry Apparatus

Key entry devices are currently employed in 24-hour bank terminals. These terminals permit bank customers to perform a number of bank transactions any time of the day without the presence of bank personnel. Basically, two conditions must be satisfied in order to activate these terminals, a coded credit card and a personal unique multidigit number.

The object of the disclosed apparatus is to preclude inadvertent disclosure of the unique number. Further, although this disclosure is directed to the specific application of banking terminals it may readily be adapted as a security measure for other devices.

An illustrative key switch embodiment of the apparatus is depicted in Figs. 1 and 2.

The operation of the secure key entry device depends on the random numeric definition of each key prior to entry of the unique number sequence. In essence, the key position cannot be mapped by visual observation because the observer cannot determine the numeric definition assigned to each key position. With the entry of the unique number sequence the keyboard is rescrambled to the conventional numeric assignment. A further restraint to observation is effected by creating an assignable numeric display with a narrow field of view.

Referring to Fig. 1, when the credit card is inserted into a slot (not shown), a pinch roller is activated so as to engage the card and provide card velocity for magnetically reading the card information. An eccentric wheel may be utilized in conjunction with the pinch roller to provide a random period of actuation for the roller arm of the microswitch M1.

The normally open condition of the microswitch M1 is set high by insertion of the credit card and its level is debounced (circuit A1) and ANDed with the B1 output of the system clock C1. This starts the decade counter DC counting up from 0 to 9 repeatedly until the microswitch M1 is opened. The multiplexor MX sequentially selects one of the ten latches L1-L10...