Abstract: A fault-tolerant transaction processing system and method stores records associated with operations of the system in order to permit recovery in the event of a need to roll back a transaction or to restart the system. At least some of the operational records are stored as a recovery log in low-speed non-volatile storage and at least some are stored as a recovery list in high speed volatile storage. Rollback of an individual transaction is effected by reference to the recovery list whereas restart of the system is effected by reference to the recovery log.

Abstract: A method and system for validating access to a computer system in an unobtrusive manner. A finite ordered series of substantive activities, such as icon manipulations, application invocations or file manipulations is specified and stored for future reference. Thereafter, each time access to the computer system is attempted, the initial activities of a prospective user are identified and compared to the stored finite ordered series of substantive activities. Access is validated and continued access permitted in response to a match between the prospective user's initial activities and the stored finite ordered series of substantive activities. In this manner, access to a computer system may be validated without the necessity of utilizing an explicit access/password screen which may be compromised. In one embodiment of the present invention, a selected application may be automatically invoked or a particular activity automatically executed in response to a validation of access.