At&t Bell Laboratories

At+t Corp.

Lucent Technologies Inc.

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

Thomas L Hiller

Meyer J Zola

Ronald A Spanke

Alex Lawrence Wierzbicki

John J Stanaway, Jr

James J Phelan

Peter James McCann

James A Davis

Mark W Beckner

Gilbert A Van Dine

Philip D Olson

Eric J Gausmann

Jin Wang

David A Pierce

Robert C Fairfield

James M Johnson, Jr

Edward H Hafer

Robert Jerrold Marks

Christopher G McHarg

Dennis L DeBruler

Scott W Pector

Ralph A Wilson, Iii

David G Furchtgott

Phillip C Chao

Bong S Choe

Joel D Peshkin

Robert W King

Frederick H Keeve, Jr

Douglas A Kimber

Voice packets transmitted by an originating wireless user for use in a half-duplex communication mode in a one to many communication session are monitored for an unexpected cessation. If an unexpected cessation of such voice packets is detected for a predetermined time period, the session server controlling the communications session is notified to release the supporting half-duplex communication paths associated with the originating user.

Wireless network with transmission control in a half-duplex voice conference mode

A method for allowing a mobile of a wireless communication simultaneous access to multiple data networks coupled to the wireless communication network. A network interface is created between network controlling elements, such as Base Station Controllers, of the wireless communication network. The network interface allows various communication channels established by the mobile to be routed to network controlling elements that are coupled to the various data networks. Information from various established communication channels are routed between various network controlling elements. Thus, a mobile is able to communicate simultaneously with different data networks. The network interface also allows handoffs to be executed with virtually no interruptions and no loss of information being exchanged between the mobile and system equipment involved in the handoff.

Method for providing multiple points of connectivity to subscribers of wireless communication networks

A method and system are disclosed for supporting overlapping IP addresses by sharing a mobile node identifier between an IWF and a Foreign Agent in a visited data (e.g., wireless) network. The mobile node identifier is stored in lookup tables associated with the IWF (Mobile Identity table) and the Foreign Agent (Visitor List table). When a data packet travels between the IWF and the Foreign Agent, the mobile node identifier is attached to it. For data packets moving in the reverse Mobile IP traffic direction (from the mobile node), the Foreign Agent uses the mobile node identifier to identify the correct Home Agent destination by finding the corresponding Home Agent address in the Visitor List table. For forward Mobile IP traffic (to the mobile node), the IWF uses the mobile node identifier to identify the correct mobile node destination by finding the corresponding link identifier in the Mobile Identity table.

Method and system for support of overlapping IP addresses between an interworking function and a mobile IP foreign agent

Pulse Code Modulation (PCM) signal streams are converted into Asynchronous Transfer Mode (ATM) cells for switching and transmission across a telecommunications network. Each cell carries one PCM sample of up to 48 different voice connections, the voice connections being selected from the PCM data streams because they have a common destination. The cells are transmitted over ATM virtual paths, each path transmitting one cell every 125 .mu.s. The ATM signals are switched by units for switching cells (cell switching), while keeping their payload contents intact, and by units for switching the signals for individual voice connections between cells of an ATM signal (cell remapping). Advantageously, ATM transmission systems interface with PCM systems without adding appreciable delay and without requiring additional buffering. Advantageously, new voice paths can be established most of the time by using available slots in the cells of existing virtual paths. Advantageously, large telecommunication networks can be implemented using a small number of switching units. Advantageously, an access switch comprising a cell mapping or distribution stage for assembling cells comprising PCM samples headed for a common output of the access switch are switched in a cell switch to a cell remap unit for collecting PCM samples headed for a common destination into individual cells of an ATM output stream, provides output signals that can be readily and efficiently switched by a transit network for distribution to other access switches of a large network.

Access switches for large ATM networks

Pulse Code Modulation (PCM) signal streams are converted into Asynchronous Transfer Mode (ATM) cells for switching and transmission across a telecommunications network. Each cell carries one PCM sample of up to 48 different voice connections, the voice connections being selected from the PCM data streams because they have a common destination. The cells are transmitted over ATM virtual paths, each path transmitting one cell every 125 .mu.s. The ATM signals are switched by units for switching cells (cell switching), while keeping their payload contents intact, and by units for switching the signals for individual voice connections between cells of an ATM signal (cell remapping). Advantageously, ATM transmission systems interface with PCM systems without adding appreciable delay and without requiring additional buffering. Advantageously, new voice paths can be established most of the time by using available slots in the cells of existing virtual paths. Advantageously, large telecommunication networks can be implemented using a small number of switching units. For use with PCM switches, it is desirable to provide supervisory signals accompanying the PCM data. Advantageously, this arrangement permits supervisory signals to be passed within an access switch thus simplifying compatibility with existing switching systems.

Intra-switch communications in narrow band ATM networks

Pulse Code Modulation (PCM) signal streams are converted into Asynchronous Transfer Mode (ATM) cells for switching and transmission across a telecommunications network. Each cell carries one PCM sample of up to 48 different voice connections, the voice connections being selected from the PCM data streams because they have a common destination. The cells are transmitted over ATM virtual paths, each path transmitting one cell every 125 .mu.s. The ATM signals are switched by units for switching cells (cell switching), while keeping their payload contents intact, and by units for switching the signals for individual voice connections between cells of an ATM signal (cell remapping). Advantageously, ATM transmission systems interface with PCM systems without adding appreciable delay and without requiring additional buffering. Advantageously, new voice paths can be established most of the time by using available slots in the cells of existing virtual paths. Advantageously, large telecommunication networks can be implemented using a small number of switching units. Advantageously, a central communications network comprising stages of cell remapping interconnected by one or more stages of cell switching provides flexibility for interconnecting large access switches; the cell remapping stage may be made part of the access switch.

ATM distribution networks for narrow band communications

Pulse Code Modulation (PCM) signal streams are converted into Asynchronous Transfer Mode (ATM) cells for switching and transmission across a telecommunications network. Each cell carries one PCM sample of up to 48 different voice connections, the voice connections being selected from the PCM data streams because they have a common destination. The cells are transmitted over ATM virtual paths, each path transmitting one cell every 125 .mu.s. The ATM signals are switched by units for switching cells (cell switching), while keeping their payload contents intact, and by units for switching the signals for individual voice connections between cells of an ATM signal (cell remapping). Advantageously, ATM transmission systems interface with PCM systems without adding appreciable delay and without requiring additional buffering. Advantageously, new voice paths can be established most of the time by using available slots in the cells of existing virtual paths. Advantageously, large telecommunication networks can be implemented using a small number of switching units.

ATM networks for narrow band communications

Pulse Code Modulation (PCM) signal streams are converted into Asynchronous Transfer Mode (ATM) cells for switching and transmission across a telecommunications network. Each cell carries one PCM sample of up to 48 different voice connections, the voice connections being selected from the PCM data streams because they have a common destination. The cells are transmitted over ATM virtual paths, each path transmitting one cell every 125 .mu.s. The ATM signals are switched by units for switching cells (cell switching), while keeping their payload contents intact, and by units for switching the signals for individual voice connections between cells of an ATM signal (cell remapping). Advantageously, ATM transmission systems interface with PCM systems without adding appreciable delay and without requiring additional buffering. Advantageously, new voice paths can be established most of the time by using available slots in the cells of existing virtual paths. Advantageously, large telecommunication networks can be implemented using a small number of switching units. Advantageously, such a cell remap unit provides a key element to the implementation of an efficient large ATM voice network.

Inter-cell switching unit for narrow band ATM networks

In accordance with the principles of this invention, Pulse Code Modulation (PCM) signal streams are converted into Asynchronous Transfer Mode (ATM) cells for switching and transmission across a telecommunications network. Each cell carries one PCM sample of up to 48 different voice connections, the voice connections selected from the PCM data streams because they have a common destination. The cells are transmitted over ATM virtual circuits, each circuit transmitting one cell every 125 .mu.s. Advantageously, ATM transmission systems interface with PCM systems without adding appreciable delay and without requiring additional buffering. Advantageously, new voice paths can be established most of the time by using available slots in the cells of existing virtual paths. This application relates to the use of the principles of this invention for implementing a large switching system or a cluster of highly interconnected smaller systems.

Establishing telecommunications call paths between clustered switching

In accordance with the principles of this invention, Pulse Code Modulation (PCM) signal streams are converted into Asynchronous Transfer Mode (ATM) cells for switching and transmission across a telecommunications network. Each cell carries one PCM sample of up to 48 different voice connections, the voice connections selected from the PCM data streams because they have a common destination. The cells are transmitted over ATM virtual circuits, each circuit transmitting one cell every 125 .mu.s. Advantageously, ATM transmission systems interface with PCM systems without adding appreciable delay and without requiring additional buffering. Advantageously, new voice paths can be established most of the time by using available slots in the cells of existing virtual paths.

Establishing telecommunications call paths in broadband communication

In accordance with the principles of this invention, Pulse Code Modulation (PCM) signal streams are converted into Asynchronous Transfer Mode (ATM) cells for switching and transmission across a telecommunications network. Each cell carries one PCM sample of up to 48 different voice connections, the voice connections selected from the PCM data streams because they have a common destination. The cells are transmitted over ATM virtual circuits, each circuit transmitting one cell every 125 .mu.s. Advantageously, ATM transmission systems interface with PCM systems without adding appreciable delay and without requiring additional buffering. Advantageously, new voice paths can be established most of the time by using available slots in the cells of existing virtual paths. This application relates to methods of establishing connections in accordance with the principles of the invention.

Establishing telecommunications calls in a broadband network

In accordance with the principles of this invention, Pulse Code Modulation (PCM) signal streams are converted into Asynchronous Transfer Mode (ATM) cells for switching and transmission across a telecommunications network. Each cell carries one PCM sample of up to 48 different voice connections, the voice connections selected from the PCM data streams because they have a common destination. The cells are transmitted over ATM virtual circuits, each circuit transmitting one cell every 125 .mu.s. Advantageously, ATM transmission systems interface with PCM systems without adding appreciable delay and without requiring additional buffering. Advantageously, new voice paths can be established most of the time by using available slots in the cells of existing virtual paths. This application relates to arrangements for converting the PCM signal streams into ATM cells.

Apparatus for interfacing between telecommunications call signals and

A synchronous protocol data formatter handles all 24-32 channels of a so-called primary rate version of a digital multiplexed interface or ISDN Primary Rates Interface for a communication system. The formatter relieves the host computer of the local area network of some highly specialized tasks, and, at the same time, provides the following augmented capabilities, which exceed those required by the C.C.I.T.T. standard, I.431:

Synchronous protocol data formatter

A switching system including a number of switching modules each having a plurality of access ports. Incoming and outgoing packet channels are extended between each switching module and an inter-module packet switch. Each of the switching modules includes both a packet switching unit and a circuit switching unit for switching information to and from the access ports. Each switching module further includes a control unit that controls the switching units and that generates inter-module control packets, and a communication interface that transmits inter-module control packets generated by the control unit on the incoming packet channel to the inter-module packet switch. The communication interface also transmits inter-module control packets received on the outgoing packet channel from the inter-module packet switch to the control unit. The inter-module packet switch concurrently packet switches inter-module control packets received on a number of the incoming packet channels, via mutltiple independent paths to a number of the outgoing packet channels.

Control information communication arrangement for a distributed control

A local area network comprising a plurality of terminals interconnected by a communication bus is disclosed. Each terminal comprises a memory, a main processor, and a co-processor. To transmit information in a communication mode, the main processor loads data into a transmit buffer area of the memory, and the co-processor reads the data from the transmit buffer area and transmits a packet on the communication bus. Similarly, the co-processor receives data from the communication bus and stores it in a receive buffer area from which it is read by the main processor for use. In an alternative mode, called the direct transfer mode, the co-processors are reconfigured so that data for transmission is read from the actual locations in memory where it is stored (not the transmit buffer area), and received data is stored in storage areas where it is expected to be used (not the receive buffer area).

Growing community of inventors

Glen Ellyn, IL, United States of America

Thomas L Hiller