At&t Bell Laboratories

American Telephone & Telegraph Co., At&t Bell Laboratories

Other

Motorola Corporation

Wu-Hon F Leung

Shi-Chuan Tu

Wayne E Hyatt

Terris L Hansen

Thomas J Baumgartner

Michael J Morgan

Jyh-Han Lin

Todd Cartwright Morgan

Warren A Montgomery

Yeou H Hwang

Gottfried W Luderer

Paul M Zislis

Deborah D Kimminau

Claudia Chandra

Lara F Morgan

Edith H Jones

Jerry W Johnson

Timothy M Jeanes

Philip R Roberts

A computer-aided method (FIG.) for developing software by which programmers may implement different features of an application as independent reusable components, even though these features affect the control flows of one another. A programmer may add new features to an application without the labor intensive tasks of examining and modifying existing code. The programmer uses a set of programming language constructs to specify nonprocedural program units, organize the program units into reusable features and integrate several features together into a feature package. An interaction detection algorithm analyzes program units and determines whether there is interaction among program units in a feature and among features in a feature package. The programmer must resolve the interaction, if detected, before the programs can be executed. A run time system specification supports the semantics of the programming language constructs and preserves the conditions that enable interaction detection.

Method to add new software features without modifying existing code

A software tool and methods for preventing software modifications from invalidating previously passed integration test cases is provided. The software tool and methods automatically modify an integrated software subroutine to collect test data for selected units of the integrated software. The software tool and methods also generate a software test environment including a driver and one or more stubs for each selected software unit. Subsequent versions of the software unit are then stimulated by the driver and stubs using the collected test data. The responses from the new version of the software unit are compared to the responses collected from the old version. Differences between the responses of the two software version are flagged, thereby preventing software modifications on the software unit from invalidating previously passed tests. Furthermore, the software tool and methods automate the incremental integration and testing of software units whose modifications are related. The software tool and methods automatically determines the set of software units to be combined, the set of test cases to exercise and the test results that must be satisfied so that previously passed integration tests will not fail. Several methods of reducing the potentially unbounded test data to a manageable amount are also described. The test data may be used to analyze important properties of the software. The test data and test environment are useful in several different phases of software development.

Methods and apparatus for preventing software modifications from invalidating previously passed integration tests

A communication session is established between a client (,) and a server (,) over a first bearer network (,). A session identifier is produced (,), which is compressed (,). Messages or packets sent between the client and server during a first connection include the compressed session identifier and a first envelope identifier. At some time the first connection is terminated, and a second connection is initiated on a second bearer network. At the occurrence of the break, at both the client and server, a session transition control block is set up and includes the first envelope identifier. The session transition control block is used to map messages or packets received after the break to the correct session after resuming the session over a second connection with a second envelope identifier.

Method for providing seamless communication across bearers in a wireless communication system

Optimal handover margins in a cellular communication system (100) are determined by computing a power budget (701) for each base station/neighbor combination in the communication system (100) and determining a probability distribution function (703) for each base station/neighbor combination in the communication system (100). Once the probability distribution function for each base station/neighbor combination is known, optimal handover margins are determined by maximizing communication system traffic over all base stations while at the same time holding call quality to acceptable levels.

Method for determining handover margins in a cellular communication

A method for use in a multimedia conferencing arrangement to control multiple concurrent calls where each call comprises one or more channels. A first call among a first set of user stations and a second call among a second set of user stations are merged into a single call comprising a plurality of channels among at least three user stations from the first and second sets. The plurality of channels of the single, merged call corresponds to a combination of channels of the first and second calls and may include a signalling channel, a voice channel, and one data channel for each data channel of the first and second calls. The method is also applicable to calls including image or video channels.

Multiple call control method in a multimedia conferencing system

Control of communication by a plurality of devices, such as computer programs and terminals, via a computer is controlled by an arrangement referred to as a connector. The connector receives a request for communication defining the devices to the communication and, in response to the request, establishes a mapping table defining the source devices and destination devices to the connection. A source device stores data in connector memory and the connector reads the mapping table to determine the destination devices for the stored data. The connector then creates a linked list coupling structure between the stored data and the determined destination devices. The destination devices issue read commands to which the connector responds by reading the stored data in accordance with the coupling structure and providing that data to the requesting device.

Method for distributing messages through a mapping table which includes

A transformation method for network conference connections where the network operations are determined based on stored information defining the original connection and stored information defining the target connection thus affording the opportunity to advantageously reuse existing paths. The paths to be deleted and the paths to be added to effect the transformation are determined such that no path is both deleted from and added to any switch. The connection information may be stored either in a central control entity or an intra-switch path information in the individual switches of the network. In the latter case, the individual switches determine their own intra-switch path additions and deletions in a distributed fashion.

Transformation method for network conference connections

A conference connection method for use in a multicast packet switching network. Once the packet switches and inter-switch links to comprise a multicast connection among three or more endpoints are determined, a check is performed to determine whether that multicast connection would to usable to effect communication in accordance with a specified transmission matrix and meeting a packet sequencing condition. The multicast connection is established only when the check indicates that the connection would meet both requirements.

Conference connection method in a multicast packet switching network

A packet switch arrangement in which a first plurality of user devices is connected to a packet network by a first interface unit and a second plurality of user devices is connected to the packet network by a second interface unit. A virtual circuit is established between the interface units and control information is exchanged over the virtual circuit. The control information defines virtual channels on the virtual circuit and ones of the first and second pluralities of user devices which are to be sources and destinations for data in the defined virtual channels. Data from user devices is packetized and transmitted in the virtual channels by the interface units in accordance with the exchanged control information. Further, packets received in virtual channels on the virtual circuit are distributed to user devices by the interface units in accordance with exchanged control information.

Multi-media virtual circuit

A telecommunication and development system for the switching of voice and data under computer control in a customer programmable environment that allows real-time modification of communication services. The computer program controlling the system is written in a nonprocedural language that allows for the direct control of the telecommunication system on the basis of state definition, event definition, and action definition. Program scripts define a particular feature, and each script consists of a plurality of triples that automatically respond to the system state and signal information to execute the necessary actions to provide part of a feature to the telecommunication system. During provision of telecommunication services, a customer can add new features that not only add new operations to the system, but modify existing operations without interfering with the present operation of the system. This is possible since the nonprocedural language allows for the direct control of interaction between features and provides for the automatic execution of required operations during state transitions. In addition, the nonprocedural language allows a feature or script to control its own deactivation or activation. Also, the software development environment is based on a standard operating system allowing for ease of development. The above features allow a customer to program his or her own individual communication unit to provide desired features without affecting the operation of the telecommunication system or the features provided to other customers.

Customer programmable real-time system

A software system written in a nonprocedural language for controlling a telecommunication system in which an internal software signal is generated when a state is exited and another internal signal is generated when a state is entered to control common operations for the state transitions. For each state, a group of instructions written in the nonprocedural language is autonomously executed in response to the exit signal to perform common exit operations for that particular state. A second group of instruction is autonomously executed in response to the entrance signal to perform common entrance operations for that particular state. Various services performed by the telecommunication system are written in scripts of groups of instructions called triples. Each triple has an event definition defining the signal that the triple will respond to and a state definition defining the state in which the system must be in before the triple can respond. Programmer productivity is increased because when new features are added, the common operations previously performed on exiting and entering a state will continue to be performed plus the programmer can add new functions to be performed upon the entrance or exiting from a state without detailed knowledge of the program implementing the previous services.

State control for a real-time system utilizing a nonprocedural language

A telecommunication system for the switching of voice and data controlled by a computer executing a nonprocedural language that allows for the explicit control of interaction between features by the program scripts executing the programs. The program scripts are written in the nonprocedural language that allows for a state definition, an event definition, and an operation definition. The triples automatically respond to the system state and system signal to execute the necessary actions to control the telecommunication system. During the run time of the system, a script whose triples implement a particular feature can control whether or not features of lower precedence are allowed to be implemented by determining whether or not allow the continuation of the processing of the system signals to the scripts of lesser precedence. In addition, a script can control its own deactivation until later conditions are met that allow the deactivation of the script.

Control of real-time systems utilizing a nonprocedural language

A method of testing interfaces between computer program modules. The individual cause/effect charts of each of the modules are used to test the interfaces between the modules by executing the test cases in the charts in such manner that each test case need only be executed once. The variables passed between modules are monitored and compared with the input conditions in the charts.

Method of testing interfaces between computer program modules

A method and apparatus for executing parts of a program process on two processors of a multiprocessor system. A home process resides in a home processor and is the destination process of all interprocess messages. The home process may call for the execution of a selected procedure on a remote processor. A call message is sent to the remote processor and a remote process is initiated. When the selected procedure has been executed in the remote processor, a return message is sent to the home process and execution of the home process is continued. Interprocess messages to the program process are received by the home processor and are forwarded to the remote processor. Interprocess messages generated by the selected procedure are transmitted by the remote processor, but are tagged with the identity of the home processor and home process.

Growing community of inventors

Downers Grove, IL, United States of America

Wu-Hon F Leung