Patent ID: 6611901
Filing Date: 2003-08-26
Classification: G06F

Abstract:
A method for maintaining electronic data at a point-in-time, comprising:generating a first data structure indicating point-in-time data at one of a first storage location and a corresponding second storage location, wherein the first and second storage locations comprise physical storage locations on a storage medium; generating a second data structure indicating point-in-time data at one of a first storage location and corresponding second storage location; generating a first relationship data structure indicating a relationship between the first storage location and corresponding second storage location; generating a second relationship data structure indicating a relationship between the first storage location and second storage location; processing a request with respect to the first storage location by processing the first relationship data structure to determine the corresponding second storage location for the first storage location and processing the first data structure to determine whether data at the first storage location was transferred to the second storage location; and processing a request with respect to the second storage location by processing the second relationship data structure to determine the corresponding first storage location for the second storage location and processing the second data structure to determine whether the point-in-time data at the first storage location was transferred to the second storage location.