Showing papers on "Data access published in 1998"

Combined internet and data access system

Abstract: The inventive system and method distributes information between databases (DB) and web servers (102), via a plurality of interconnected platforms (105) or nodes. A session manager,that is resident on only one platform, manages information flow between the databases and the web servers. The session manager uses a manager thread to determine which platform will operate on the request. At least one data gateway (106) resides on each platform. A processing thread of the data gateway invokes an application module to create an application, which retrieves the requested information from the database. The processing thread translates the request into a format useable by the application. The processing thread retrieves a dynamic HTML template file and uses the information retrieved from the database to populate the HTML template file to form the response to the request, and passes the request onto the global network server.

Method of servicing data access requests from users

Abstract: A method of servicing data access requests from users connected to a distributed service network comprises determining the user, the communications client used to connect to the network and the data stream conversions required for the user to communicate between the communications client and one or more accessed services. The method provides that the data access is provided independent of the connection point and the data communications client.

Data access control apparatus for limiting data access in accordance with user attribute

Abstract: This invention provides a data access control apparatus arranged to automatically set access right information limiting data access, in accordance with a user attribute when a user accesses a database. In setting, for a plurality of users, access right information corresponding to each user, the load on an operator can be reduced, and access right information setting errors can be prevented. An automatic setting unit reads out information from a login management information file and an employee information file on the basis of definition information of a definition files to automatically generate a user access right management file which stores a login ID, an item access right, and a record access right group code for each user. When a login ID is input in accessing the employee information file, a setting controller refers to the management file to determine a user group to which the user belongs and an access enabled/disabled state of the data on the basis of the access right made to correspond to this user group.

Highly available cluster virtual disk system

Abstract: A cluster implements a virtual disk system that provides each node of the cluster access to each storage device of the cluster. The virtual disk system provides high availability such that a storage device may be accessed and data access requests are reliably completed even in the presence of a failure. To ensure consistent mapping and file permission data among the nodes, data are stored in a highly available cluster database. Because the cluster database provides consistent data to the nodes even in the presence of a failure, each node will have consistent mapping and file permission data. A cluster transport interface is provided that establishes links between the nodes and manages the links. Messages received by the cluster transports interface are conveyed to the destination node via one or more links. The configuration of a cluster may be modified during operation. Prior to modifying the configuration, a reconfiguration procedure suspends data access requests and waits for pending data access requests to complete. The reconfiguration is performed and the mapping is modified to reflect the new configuration. The node then updates the internal representation of the mapping and resumes issuing data access requests.

Method and system for an air interface for providing voice, data, and multimedia services in a wireless local loop system

Abstract: A method and system for implementing an air interface for a Time Division Duplex (TDD) Code Division Multiple Access (CDMA) wireless local loop system that utilizes unique embedded concentrated access and embedded data access in a Wireless Local Loop (WLL) is described. The method and system further provides for dynamic pool sizing of the access channels. The interface is designed to support POTS (Plain Old Telephone), ISDN, and direct data service in a point to multi-point configuration. The interface is inherently flexible so as to provide Enhanced Bandwidth and quality of service (QOS) via CDMA. Channel concatenation (multi-code modulation) provides a multiplicity of channels. The system utilizes frequency division duplex (FDD) operation so as to double capacity. The system further utilizes scaleable architecture for bandwidth expansion and higher data rate services.

Use of web technology for subscriber management activities

Abstract: External entity (36) data access to the customer administrative system (14) and database network elements (16) of a telecommunications network (10) is provided through a web-server (32) and an Internet (30) connection. The integrity and security of any stored data is protected through the use of a firewall (34) implemented at the web-server. In one aspect, an interface (12) is connected between the customer administrative system (14) and database network elements (16) and is also connected to the web-server (32) to handle external entity (36) requests by specifying not only which actions need to be taken but also routing the request to a proper destination. In a second aspect, the interface (12) is by-passed with respect to the handling of external entity (36) requests, with the web-server (32) specifying the actions to be taken and routing the request to the proper destination.

Semiconductor memory capable of writing and reading data

Abstract: A nonvolatile semiconductor memory serving as a semiconductor memory which is capable of erasing data in a batch comprises four banks constituting a storage circuit, a bank control circuit for instructing access to respective banks (writing, reading, etc.), and a status signal output circuit connected to the bank control circuit. The status signal output circuit outputs status signals for instructing access status of respective banks. The status signals are outputted to an external device through a data bus. With such a construction, the access status of respective banks can be easily grasped, so that the data access to the semiconductor memory can be enhanced with efficiency, thereby realizing high speed data processing.

Chipset configured to perform data-directed prefetching

Abstract: A chipset is configured to communicate between one or more processors and other components of the computer system, including a main memory. The chipset communicates read memory operations initiated by the processors to the main memory, and returns the data provided therefrom to the processors. Additionally, the chipset includes circuitry configured to select a portion of the data and to generate a prefetch address using the data. Accordingly, a pointer included in the data can be used to generate a prefetch address. The prefetching does not rely on observing the data access pattern. Instead, the data being transferred in response to a memory operation is used to generate a prefetch address (i.e. “data-directed prefetching”). In one embodiment, various programmable features are included in the chipset to specify which portion of the data to select, when to perform prefetching, etc. Accordingly, the prefetching mechanism is flexible to adapt to a variety of data structures and patterns of access to those data structures. By implementing the data-directed prefetching algorithm in the chipset, the data can be selected and a prefetch address generated early in the performance of the memory operation. Accordingly, the effective memory latency of the prefetched data may be substantially reduced due to the early initiation of the prefetch operation.

Container independent data binding system

Abstract: A container independent data binding system that independently facilitates data binding by way of a binding agent object on behalf of any data consumer and/or data source that conforms to the necessary interfaces and protocols. The binding agent facilitates data binding and transparent data access for any visual and/or non-visual object, in addition to control data verification for client-side control validation independent of a container, binding collection for non-data aware objects that can benefit from data binding, data conversion and formatting to control User Interface displays in the context of data binding, and repeater control to facilitate a list view for visual objects, for any object that requires and requests access to these features rather than individually implementing these features without binding agent support.

Method and apparatus providing system availability during DBMS restart recovery

Abstract: A method and apparatus to provide DBMS restart recovery that allows transactions to access data that does not have restart recovery work pending. Access to data requiring restart recovery work to be performed is restricted, and a transaction is denied access to this data. In another embodiment, the invention allows certain transactions to access restricted data that has restart recovery work pending. These transactions are transactions that do not require data consistency. Regardless of the embodiment, the invention allows full recovery to be completed concurrent to the processing of new transactions requiring access to the database. An amount of restart recovery processing may be postponed until after the DBMS has begun accepting new work requests.

Mechanism for reliable update of virtual disk device mappings without corrupting data

Abstract: A cluster implements a virtual disk system that provides each node of the cluster access to each storage device of the cluster. The virtual disk system provides high availability such that a storage device may be accessed and data access requests are reliably completed even in the presence of a failure. To ensure consistent mapping and file permission data among the nodes, data are stored in a highly available cluster database. Because the cluster database provides consistent data to the nodes even in the presence of a failure, each node will have consistent mapping and file permission data. A cluster transport interface is provided that establishes links between the nodes and manages the links. Messages received by the cluster transports interface are conveyed to the destination node via one or more links. The configuration of a cluster may be modified during operation. Prior to modifying the configuration, a reconfiguration procedure suspends data access requests and waits for pending data access requests to complete. The reconfiguration is performed and the mapping is modified to reflect the new configuration. The node then updates the internal representation of the mapping and resumes issuing data access requests.

Survivable and scalable data system and method for computer networks

Abstract: A fully scalable and survivable network architecture and method is disclosed. In particular, a system for providing network or intranet processing and stored data access and an associated method is provided. The system includes a plurality of sets of at least first and second application processors. Each of the first and second processors within a set apply substantially the same application. One or more switches operatively connect to at least the first and second processors and a plurality of data storage devices. The data stored in the data storage device is associated with the application and mirrored, and at least the first and second processors operate at substantially the same time to obtain data. Both sources of mirrored data are operational at the same time to output data.

Method and system for providing performance guarantees for a data service system of a data access network system

Abstract: A data service system is described that includes a plurality of data content sites and is coupled to a number of user terminals via a network. The data service system also includes a system for providing performance guarantees for the content sites. The system for providing performance guarantees includes a plurality of class processors, each for controlling access throughput of one of the content sites in accordance with a predetermined admission control policy. When one of the class processors receives an access request for one of the content sites, that class processor determines if the access request should be accepted based on the corresponding admission control policy and sends the access request to the corresponding content site when accepting the access request. The system also includes a classifier that determines to which one of the class processors the access request should be sent. A method of controlling access throughput of the content sites is also described.

Method and apparatus for controlling application access to limited access based data

Abstract: An application registration data generator, on a per application basis, generates application registration data that contains at least application identification data, such as, the name of a software application or a pathname to a software application, and stored unique application verification data that is based on executable file data. A data access determinator determines whether a calling application should be allowed access to the limited access based data by, for example, computing a hash value of the executable file and checking whether this hash value matches the corresponding stored unique application verification data. If there is a match, the application is granted access to the user's cryptographic parameters, privilege data, or other limited access based data on a per application basis.

Method and apparatus for combining undo and redo contexts in a distributed access environment

Abstract: A method and apparatus for combining undo and redo contexts in a distributed access environment is described. A first user gains access to data items residing on a database and modifies the data items. The modifications are incorporated into a user activity log. A subsequent user also accesses and modifies the same data items, which modifications are merged into the activity log. The merged activity log forms one sequential well ordered set of actions, including the modification made by the first user and the subsequent user. The user activity logs may be created for individual data items, individual users or for all modifications made to separate data items. A system for combining undo and redo contexts in a distributed access environment is also described.

Active polling by network LDAP directory

Abstract: The present invention is an apparatus for controlling client node access to data items maintained in a storage device. The data items include volatile data items. The apparatus comprises a communication device for communicating with multiple client nodes; and a processor, coupled to the storage device for polling the client nodes to exchange (e.g., retrieve and/or transmit) data related to the volatile data items, via the communication device. The processing system further controls client node access to the data items of the storage device. In this way, the apparatus and method of the present invention remedies the problems associated with directory server overload.

Mechanism for maintaining constant permissions for multiple instances of a device within a cluster

Abstract: A cluster implements a virtual disk system that provides each node of the cluster access to each storage device of the cluster. The virtual disk system provides high availability such that a storage device may be accessed and data access requests are reliably completed even in the presence of a failure. To ensure consistent mapping and file permission data among the nodes, data are stored in a highly available cluster database. Because the cluster database provides consistent data to the nodes even in the presence of a failure, each node will have consistent mapping and file permission data. A cluster transport interface is provided that establishes links between the nodes and manages the links. Messages received by the cluster transports interface are conveyed to the destination node via one or more links. The configuration of a cluster may be modified during operation. Prior to modifying the configuration, a reconfiguration procedure suspends data access requests and waits for pending data access requests to complete. The reconfiguration is performed and the mapping is modified to reflect the new configuration. The node then updates the internal representation of the mapping and resumes issuing data access requests.

Dynamic query operator scheduling for wide-area remote access

Abstract: Distributed databases operating over wide-area networks such as the Internet, must deal with the unpredictable nature of the performance of communication. The response times of accessing remote sources can vary widely due to network congestion, link failure, and other problems. In such an unpredictable environment, the traditional iterator-based query execution model performs poorly. We have developed a class of methods, called query scrambling, for dealing explicitly with the problem of unpredictable response times. Query scrambling dynamically modifies query execution plans on-the-fly in reaction to unexpected delays in data access. In this paper we focus on the dynamic scheduling of query operators in the context of query scrambling. We explore various choices for dynamic scheduling and examine, through a detailed simulation, the effects of these choices. Our experimental environment considers pipelined and non-pipelined join processing in a client with multiple remote data sources and delayed or possibly bursty arrivals of data. Our performance results show that scrambling rescheduling is effective in hiding the impact of delays on query response time for a number of different delay scenarios.

Data socket system and method for accessing data sources using URLs

Abstract: A Data Socket client and associated applications and/or tools which provide programs with access to data from various sources and having various types or formats, wherein the access is provided invisibly to the user. The Data Socket client allows the user or program to access any data source available on the user's machine as well as data anywhere on a network, such as a LAN, WAN or the Internet. In the preferred embodiment, the Data Socket client addresses data sources or I/O sources using a URL (uniform resource locator), much the way that a URL is used to address web pages anywhere in the world. The present invention also includes new Data Socket URLs which allow the user to access I/O sources.

Efficient database implementation of express information models

Abstract: The research presented in this thesis describes a framework for database implementation of EXPRESS information models. EXPRESS models describe complex structures and correctness conditions for engineering activities, and are defined by the ISO-10303 Standard for Product Data Exchange (STEP). These models are a substantial engineering resource, and industry desires to use them to integrate design and manufacturing processes. Databases built around STEP models are essential because they provide content that integrated engineering processes understand. The Standard Data Access Interface (SDAI) is a STEP API for EXPRESS-defined data. Prototypes have attempted to provide SDAI access by implementing each SDAI operation as one or more native operations directly upon the database. A direct binding can be costly, as it requires completely new software for each database. This work proposes several SDAI implementation architectures that offer alternatives to a direct binding. To evaluate the real-world performance of implementations, this work defines a set of representative benchmarks on the STEP AP-203 information model. AP-203 contains information such as CAD geometry and product configuration that is common to all of the STEP models. The STEPStone benchmarks cover information that is modeled in an existence dependent style (PartStone, part versions), a navigational style (NURBStone, geometry), and a mix of the two (BOMStone, bill of material). The results of timing experiments using these benchmarks are presented. The experiments evaluate the performance of direct-binding SDAI implementations built on relational and object-oriented databases, and examine the effect of various optimizations on binding performance. Analysis of the timing results provide the relative cost of access for each system, and allow us to determine when each implementation style will be most advantageous. In addition, these experiments provide insight about the use of SDAI access versus traditional access strategies.

A Performance Prediction Framework for Data Intensive Applications on Large Scale Parallel Machines

Abstract: This paper presents a simulation-based performance prediction framework for large scale data-intensive applications on large scale machines. Our framework consists of two components: application emulators and a suite of simulators. Application emulators provide a parameterized model of data access and computation patterns of the applications and enable changing of critical application components (input data partitioning, data declustering, processing structure, etc.) easily and flexibly. Our suite of simulators model the I/O and communication subsystems with good accuracy and execute quickly on a high-performance workstation to allow performance prediction of large scale parallel machine configurations. The key to efficient simulation of very large scale configurations is a technique called loosely-coupled simulation where the processing structure of the application is embedded in the simulator, while preserving data dependencies and data distributions. We evaluate our performance prediction tool using a set of three data-intensive applications.

Method and system for protocols for providing voice, data, and multimedia services in a wireless local loop system

Abstract: A method and system for implementing various protocols for a Time Division Duplex (TDD) Code Division Multiple Access (CDMA) wireless local loop system that utilizes unique embedded concentrated access and embedded data access in a Wireless Local Loop (WLL) is described. The method and system further provides for dynamic pool sizing of the access channels. The protocols support POTS (Plain Old Telephone), ISDN, and direct data service in a point to multi-point configuration. The protocols are inherently flexible so as to provide Enhanced Bandwidth and quality of service (QOS) via CDMA. Channel concatenation (multi-code modulation) provides a multiplicity of channels. The system utilizes frequency division duplex (FDD) operation so as to double capacity. The system further utilizes scaleable architecture for bandwidth expansion and higher data rate services.

Planning support : Hardware and software in search of a system

Abstract: Urban planning has adopted a variety of modeling and data manipulation technologies over the last 30 years Computer products such as traffic modelers, geographic information systems, and multimedia have been brought into planning organisations to perform specific tasks More recently, the developers of software that support planning have begun to look towards integration of various operations and have begun referring to their products as planning support systems (PSS) In general, however, PSS remain a specific purpose tool, or a set of tools, loosely coupled to provide for a small range of operations In general there is little system This paper reviews current trends in spatial hardware and software development, and suggests that at this stage we have considerable utility but little system It goes on to suggest that the potential for the emergence of true `systems' does exist The key is effective integration which gives the system operator common access to data and smooth transition between systems modules

Access control system having automatic download and distribution of security information

Abstract: A system for controlling access to areas of one or more buildings by automatically downloading transaction data from an external database to a central database, and distributing security information automatically from the central database to access controllers of the system in response to changes in the central database due to the downloaded transaction data. The transaction data represents changes or additions in employee and/or badge information stored in the external database. Each of the access controllers are coupled to one or more card readers. The card reader read data from badges and any pin number data entered at a keypad of the reader. The access controllers each make access decisions responsive to data from the card reader for controlling locking mechanisms to doors accessing areas of buildings. The system includes a programmed computer server for reading transaction data from the external database, and a central database into which the computer server automatically downloads and maps the read transaction data. When the information downloaded into the central database affects access to areas, the computer server automatically distributes security information from the central database to the access controllers through access control drivers which are each connected to one or more access controllers. Each of the access controllers makes access decisions to areas responsive to data received from the readers coupled to the access controller in accordance with received security information. Each of the access controllers can send a message via the access control drivers to the computer server indicating whether the security information was accepted by the access controller. If the security information was not accepted, the computer server stores the security information in the central database for later resending to the access controller.

Khazana: an infrastructure for building distributed services

Abstract: Essentially all distributed systems, applications, and services at some level boil down to the problem of managing distributed shared state. Unfortunately, while the problem of managing distributed shared state is shared by many applications, there is no common means of managing the data-every application devises its own solution. We have developed Khazana, a distributed service exporting the abstraction of a distributed persistent globally shared store that applications can use to store their shared state. Khazana is responsible for performing many of the common operations needed by distributed applications, including replication, consistency management, fault recovery, access control and location management. Using Khazana as a form of middleware, distributed applications can be quickly developed from corresponding uniprocessor applications through the insertion of Khazana data access and synchronization operations.

Computer architecture for multi-organization data access

Abstract: Users are provided access to locally controlled data under centrally controlled rules of access. First, users request access to one or more agency databases from an enterprise system. After access is authorized using any known technique, users access agency databases, via the Internet, intranet(s) or other public or enterprise networks, using enterprise standard forms. Industry standard display programs, such as web browsers may be used to display the forms. The data fields on the forms are defined by agency and user profiles stored in enterprise databases. The content of the fields are supplied by the agency databases.

Managing access to data in a distributed database environment

Abstract: A method and an apparatus for managing access to data on a distributed database system is provided. A snapshot list is generated for a transaction executing on the distributed database system. The snapshot list specifies snapshot times for a plurality of locations in the distributed database system. The snapshot times are determined based upon the location of a data item and the location where the transaction is executing. The selection of a version of the data item to be provided to the transaction is made based upon the snapshot time for the location associated with the data.

System for concurrent cache data access by maintaining and selectively merging multiple ranked part copies

Abstract: A system for providing multiple hosts with concurrent access to cached data by selectively generating, maintaining, modifying, and consolidating multiple versions of data items in cache memory to efficiently accommodate data access requests by the hosts. Data associated with a logical track is represented in cache by a number of cache track image parts. Each part represents one or more records in cache, where multiple parts may exist in cache for the same logical track. The provision of multiple parts supports concurrent access by multiple operations or "processes" to data associated with a track. Namely, each part is given a "status" selected from a predetermined catalog of statuses; the assigned status thus establishes the permissible manner of accessing that part. Depending upon a part's status, the part may be used by one process (e.g. Read) or by multiple processes concurrently (e.g. Read and Destage). Other part statuses dedicate a part to a single process (e.g. Write). Multiple parts, not being actively used by a process, may be combined by a merge function to represent the most current image of the track.

Design, Implementation, and Performance of the LHAM Log-Structured History Data Access Method

Abstract: Numerous applications such as stock market or medical information systems require that both historical and current data be logically integrated into a temporal database. The underlying access method must support different forms of “time-travel” queries, the migration of old record versions onto inexpensive archive media, and high insert and update rates. This paper introduces a new access method for transaction-time temporal data, called the Logstructured History Data Access Method (LHAM) that meets these demands. The basic principle of LHAM is to partition the data into successive components based on the timestamps of the record versions. Components are assigned to different levels of a storage hierarchy, and incoming data is continuously migrated through the hierarchy. The paper discusses the LHAM concepts, including concurrency control and recovery, our full-fledged LHAM implementation, and experimental performance results based on this implementation. A detailed comparison with the TSB-tree, both analytically and based on experiments with real implementations, shows that LHAM is highly superior in terms of insert performance while query performance is in almost all cases at least as good as for the TSB-tree; in many cases it is much better,

Dynamic granular locking approach to phantom protection in R-trees

Abstract: Over the last decade (1988-98), the R tree has emerged as one of the most robust multidimensional access methods. However, before the R tree can be integrated as an access method to a commercial strength database management system, efficient techniques to provide transactional access to data via R trees need to be developed. Concurrent access to data through a multidimensional data structure introduces the problem of protecting ranges specified in the retrieval from phantom insertions and deletions (the phantom problem). Existing approaches to phantom protection in B trees (namely, key range locking) cannot be applied to multidimensional data structures since they rely on a total order over the key space on which the B tree is designed. The paper presents a dynamic granular locking approach to phantom protection in R trees. To the best of our knowledge, the paper provides the first solution to the phantom problem in multidimensional access methods based on granular locking.