摘要:
A data processing system having a host computer including a key manager, a control unit connected to the host computer, a data storage unit (such as a tape drive) controlled by the control unit, and data storage medium for storing data thereon to be written to or read from by the data storage unit. The key manager stores a data structure having at least one record having a volume serial number, as start location, a length entry, and a key for encrypting and decrypting data on the data storage medium. A data storage medium (such as data tape) is mounted on the data storage unit, and a volume recorded on the tape is retrieved. The control unit retrieves the data structure from the key manager and matches the volume serial number recorded in the retrieved data structure with the volume serial number retrieved from the data storage medium. It they match, the control unit passes to the data storage unit, commands to turn on or turn off encryption dependent upon the location where data is written by the data storage unit onto the data storage medium, or to turn on or turn off decryption dependent upon the location where data is read by the data storage unit from the data storage medium.
摘要:
A data processing system having a host computer including a key manager, a control unit connected to the host computer, a data storage unit (such as a tape drive) controlled by the control unit, and data storage medium for storing data thereon to be written to or read from by the data storage unit. The key manager stores a data structure having at least one record having a volume serial number, as start location, a length entry, and a key for encrypting and decrypting data on the data storage medium. A data storage medium (such as data tape) is mounted on the data storage unit, and a volume recorded on the tape is retrieved. The control unit retrieves the data structure from the key manager and matches the volume serial number recorded in the retrieved data structure with the volume serial number retrieved from the data storage medium. It they match, the control unit passes to the data storage unit, commands to turn on or turn off encryption dependent upon the location where data is written by the data storage unit onto the data storage medium, or to turn on or turn off decryption dependent upon the location where data is read by the data storage unit from the data storage medium.
摘要:
A method, apparatus and program product for encryption/decryption of data on a volume of data storage media including dividing the volume into a plurality of locations, assigning a unique key to each location for encryption/decryption of data in the respective location of the volume, mapping the locations and keys in the key manager, and encrypting/decrypting data on the volume based on the data's physical location on the volume. The owning entity owning each location on the volume may also be mapped, and the keys for each location owned by the same owning entity may be the same.
摘要:
Disclosed are a method, system and computer program for purging data in a data storage system comprising a plurality of hosts one or more data storage devices and a controller, the controller including a cache. In accordance with the present invention, a communication interface is implemented between operating systems (OS) and the storage controller, of a multi-host data storage system, to signal the storage controller when the host is being shutdown. When the storage controller gets the signal, the controller purges the controller cache of any pages belonging to that host and puts those pages back into the free pool.
摘要:
A memory management method is disclosed. In response to a process running in a first memory and the first memory becoming constrained by demands from another process, information in the first memory is paged out to a second memory. In response to a request to further run the process, the information from the second memory is paged into a read cache and then into the first memory, while a copy of the information is left the read cache. In response to the information in the first memory then being updated and the copy of the information in the read cache now becoming stale, the now stale copy of the information in the read cache is checked for and purged, and indication is provided that the read cache has been purged.
摘要:
A method, data processing system and program product for protecting against stale page overlays which includes executing a process in memory of the data processing system. A storage controller pages data from the memory to a disk in pages when the memory is constrained by other processes being executed by the data processing system. Data is then paged from the disk into memory in a one or more paged-in pages. The paged-in page is updated with updated data by the process, and the version on the disk is marked as stale. The storage controller commands the disk to make the stale disk version of the updated paged-in page as write-only, thereby providing that the disk version may be overwritten with new data while providing that the disk version cannot be read.
摘要:
According to exemplary embodiments, a computer program product for testing virtual systems includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method comprises randomly selecting commands from a pool of commands, generating by a computer a test sequence from the randomly selected commands and simulating performance of the test sequence for a simulated virtual system that is a model of a virtual system. The method also includes recording simulated results of the simulated performance, performing the test sequence on the virtual system, recording actual results of the test sequence being performed on the virtual system, and determining by a computer if the virtual system is operating properly based on a comparison of the simulated results to the actual results.
摘要:
Embodiments of the present invention provide a method, system and computer program product for software requirements extraction from external sources for software development. In an embodiment of the invention, a method for software requirements extraction from external sources for software development includes retrieving content from over a computer communications network pertaining to a product. The content can include by way of example, a Web page, e-mail message, instant message, blog posting or social network posting, to name only a few. Within the content, a modal verb can be identified and text extracted that is proximate to the modal verb. Thereafter, a requirement can be generated for a revision of the product based upon the extracted text. Optionally, the requirement can be ranked according to the modal verb, for example, an imperative modal verb can correspond to a higher ranking than a suggestive modal verb.
摘要:
A system thinker application receives a first issue, a first resolution to the first issue, and a first plurality of skills. The system thinker application searches a system environment electronic profile for a second issue, a second resolution to the second issue, and a second plurality of skills, wherein the system environment electronic profile contains a plurality of component profiles, and wherein the plurality of component profiles contain a second issue, a second resolution to the second issue, and a second plurality of skills. The system thinker application determines if the first issue, the first resolution to the first issue, and any one of the first plurality of skills are similar to any one of the second issue, the second resolution to the second issue, and any one of the second plurality of skills. The system thinker application adds skills to the system environment electronic profile and the component profile.
摘要:
Embodiments of the invention include methods for providing policy-driven, adaptive, multi-factor authentication procedures. A pool of potential authentication challenges is defined. Each of the potential authentication challenges is assigned a category and a weighted difficulty level. One or more authentication challenges are selected from the pool of potential authentication challenges using one or more security policies that are based upon the assigned category and the assigned weighted difficulty level, wherein a quantity of authentication challenges is determined using the one or more security policies. One or more historical access patterns are utilized in conjunction with the selected one or more authentication challenges to authenticate a user, wherein the historical access patterns include at least one of an access time or an access location. One or more dummy challenges are used to authenticate the user.