Browse Prior Art Database

Emulated Keylock for Computer

IP.com Disclosure Number: IPCOM000039250D
Original Publication Date: 1987-May-01
Included in the Prior Art Database: 2005-Feb-01
Document File: 2 page(s) / 31K

Publishing Venue

IBM

Related People

Anthony, BO: AUTHOR [+3]

Abstract

Nonvolatile random access memory (NVRAM) 10, connected to computer 12 particularly to its input 14 (via line 11), provides the output signal "unique password entered" (on line 11) when a unique password has been entered in computer 12, and this signal, applied to computer input 14, puts computer 12 in operating state at this time and causes computer 12 to be locked in an inoperative state until this unique password has been entered into the computer. Previously, a mechanical keylock switch connected to computer input 14 had been used when it was desired to render the computer operative, and RAM 10 replaces the keylock switch.

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Emulated Keylock for Computer

Nonvolatile random access memory (NVRAM) 10, connected to computer 12 particularly to its input 14 (via line 11), provides the output signal "unique password entered" (on line 11) when a unique password has been entered in computer 12, and this signal, applied to computer input 14, puts computer 12 in operating state at this time and causes computer 12 to be locked in an inoperative state until this unique password has been entered into the computer. Previously, a mechanical keylock switch connected to computer input 14 had been used when it was desired to render the computer operative, and RAM 10 replaces the keylock switch. Following power-on, computer 12 begins instruction execution and prior to IPL (initial program load) of the system control program, diagnostic code tests to determine that the hardware hardware is functioning properly and initializes the system. Checking the state of the keylock is part of the system initialization code. For this emulated keylock, this involves reading data which specifies the current state of the keylock from nonvolatile storage 10 within the system. The program tests the state of the emulated keylock and, based on the keylock state, a specific action occurs. If the emulated keylock is in the secure or locked state, the diagnostic code prevents IPL of the system control program and waits for a change on line 11 in the keylock state. If the state of the emulated keylock is normal or unlocked, the system control program is IPLed and the normal user interface to the system is brought on line. A service state of the emulated keylock would cause the program to invoke specific service functions which are not available during normal system operation. A master password is loaded into nonvolatile storage 10 during system manufacture, and all syst...