Harrison L Freeman

Title: Innovations of Harrison L Freeman

Introduction

Harrison L Freeman is a notable inventor based in Kasson, MN (US). He has made significant contributions to the field of optical media technology, holding a total of 3 patents. His work primarily focuses on enhancing the efficiency and management of Write Once Read Mostly (WORM) volumes.

Latest Patents

Freeman's latest patents include a "Directory structure for worm optical media." This invention discloses a directory structure that supports a multi-level tree structure containing several paths. When a user defines the first path on the WORM volume, a file directory group is created for that path. A path directory entry pointing to this file directory group is written to the path directory group. Files having this path name are initially written into the first data file area next to this file directory group. The first data file area grows as data is written into it. When a second path is defined, the first data file area is closed, and a second file directory group is created on the WORM volume next to the first data file area, thereby wasting little if any space. The path directory group is updated with a new path directory entry that points to this new file directory group. Files having this second path name are written into a growing second data area. If the user now wants a file having the first path name to be written to the disk, a file directory entry is placed in the first file directory group, but the file itself is written into the growing second data file area. In this manner, files are associated with directory entries by a common path name, not necessarily physical location on the disk, although files tend to be relatively close to their associated directory entry.

Another significant patent is the "System and method for worm volume management of new and updated data." This invention provides a computer system and method for efficiently managing WORM volumes on mass optical storage devices. A configuration menu asks the user to enter a threshold percentage from 1-100%. The threshold percentage is multiplied by the volume size to determine a threshold block address. New files are written sequentially to the WORM volume up to but not exceeding the threshold block address, unless a threshold override indicator is enabled. Space on the WORM volume between the threshold block address and the end of the WORM volume is reserved for updated files. Updated files can be stored anywhere on the WORM volume, including above the threshold