Abstract: The present invention improves speed and reduces complexity in a digital signature scheme that uses elliptic algebra. The signature scheme generates two points that are compared. If the points do not match, the signature is not authentic. The present invention reduces computations by comparing only the x coordinates of the two generated points. The invention provides a scheme for deducing the possible values of the x- coordinate of a sum of two points using only the x coordinates of the original two points in question. The present invention provides a scheme that limits the possible solutions that satisfy the equation to two (the authentic signature and one other). Because of the large number of possible inauthentic solutions, the chance of a false authentic signature is statistically insignificant.
Abstract: The present invention discloses a system for transparent local and distributed memory management. The invention overcomes the prior art's requirement of keeping track of whether a memory space allocated to a new object or a new program or data structure can be reclaimed. According to the present invention an autorelease pool is created at the beginning of a new duty cycle. The autorelease pool retains the newly allocated memory space during the duty cycle. The autorelease pool is automatically disposed of at the end of the duty cycle. As a result of disposing the autorelease pool the newly allocated memory space is reclaimed (i.e., deallocated). The present invention is useful in distributed networks where different programming conventions on remote and local machines made the prior art's memory management task particularly difficult. The present invention is also useful in an object-oriented programming environment.
Type:
Grant
Filed:
January 31, 1995
Date of Patent:
November 11, 1997
Assignee:
NeXT Software, Inc.
Inventors:
Blaine Garst, Ali Ozer, Bertrand Serlet, Trey Matteson
Abstract: The present invention is a method that enables single release of applications for multiple architectures and operating systems and to provide ease of use of applications in multiple architecture environments. The present invention provides a single file that contains separate object code each of multiple architectures. A special header on the file identifies each section of object code and includes pointers to its starting location. When the file is to be executed on a particular architecture, the resident operating system identifies that block of object code most suited for that particular architecture and environment. That section of code is then loaded into memory for execution. Each architecture in the file is specified by CPU-type and CPU sub-type. For each CPU type or CPU sub-type, file offset, file size and alignment is also provided. Padded bytes are provided to place each member on its specific alignment.
Type:
Grant
Filed:
February 28, 1995
Date of Patent:
February 18, 1997
Assignee:
NeXT Software, Inc.
Inventors:
Avadis Tevanian, Michael Demoney, Kevin Enderby, Douglas Wiebe, Garth Snyder
Abstract: The present invention improves speed and reduces complexity in a digital signature scheme that uses elliptic algebra. The signature scheme generates two points that are compared. If the points do not match, the signature is not authentic. The present invention reduces computations by comparing only the x coordinates of the two generated points. The invention provides a scheme for deducing the possible values of the x-coordinate of a sum of two points using only the x coordinates of the original two points in question. The present invention provides a scheme that limits the possible solutions that satisfy the equation to two (the authentic signature and one other). Because of the large number of possible inauthentic solutions, the chance of a false authentic signature is statistically insignificant.