Abstract: Look-ahead control techniques and a variable attenuator are used to solve the known problem of differential attenuation of photonic intensities between time slots are delayed differently in delay paths that have different losses which optical time slot interchangers have. The result of the look-ahead control techniques and variable attenuator is a data frame in which the widely varying photonic intensities are equalized to a substantially similar level, thereby greatly reducing the bit error rate of the downstream receiver/demodulator.

Abstract: A system and method that controls node congestion in a packet switching network by allowing the congested node to seize control of transmission on the packet switching network and not relinquishing control until it has drained its buffer of the backlog of packets. In response to the node's buffer reaching a predetermined occupancy level, the node requests from the network's arbiter for exclusive transmission rights on the network. When the node receives transmission rights, the node continues to process packets in the buffer. When the occupancy of the buffer reaches a second predetermined threshold, the node releases the transmission right, and thus permits other nodes to transmit packets to it (and to other nodes) again.

Abstract: 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.

Abstract: A system for relaying CDMA packetized data from a cell site or sites to a destination speech processor. The CDMA packetized data, is received at the cell site and is sent in its packetized form along with a destination address to a packet switch. A packet handler at the packet switch receives the CDMA data packets and forwards them on a packet bus. If the destination speech processor assigned to that call is connected to the packet bus, it recognizes its own address and processes the data packet.

Abstract: A system and method for delivering packetized data representing radio signals to and from cell sites, and to and from a destination point via a fast packet network. Each cell site includes an interface for packetizing the radio signals and transmitting the packetized data to its destination. The destination could be a delivery point at a switch connected to the telephone network, which then converts the packetized data into a form usable by the telephone network. Alternatively, the destination point could be another cell site, which then depacketizes the radio signal and retransmits the radio signal to another wireless communication device without connecting to the telephone network.

Abstract: Soft handoff is provided in a mobile-to-mobile call in a cellular communication system, wherein a first mobile is moving from a first cell to a second cell, and the second mobile is in a third cell. The first mobile requests a handoff from the first cell to the second cell. In response, information regarding the call handoff is sent to the second and third cells. During handoff, the first and second cells receive radio transmission from the first mobile, and they both translate the transmissions into electronic data, packetize the data, and send the packetized data to the third cell. The third cell sends packetized data from the second mobile to both the first and second cells. Further, the second mobile may also move from the third cell to a fourth cell. The second mobile requests a handoff from the third cell to the fourth cell. Call data is sent to the fourth cell identifying the first and second cells. Call data is sent to the first and second cells identifying the fourth cell.

Abstract: A data stream is converted from a synchronous transfer mode (STM) to an asynchronous transfer mode (ATM) by extracting data of a number of payload signals from the data stream, writing data of the payload signal into a random access memory (RAM), separately recording address locations of the data of each of the payload signals in separate buffers, directing the RAM to separately read the data of the payload signals, and attaching a cell header to the data read from the RAM to form ATM cells.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: An Optical Time Slot Interchange (OTSI) Apparatus that has relatively low optical fiber requirements and good attenuation and signal-to-noise characteristics. This OTSI uses parallel feedback (PFB) to provide the delays. This PFB OTSI can be implemented with an n.times.n optical crossbar switch. The PFB OTSI is conditionally, i.e., rearrangeably, non-blocking for 16.times.16 crossbar switch implementations if a controller using the control method of the invention is also included.

Abstract: 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.

Abstract: A system for delivering packetized data in a network comprising a plurality of packet switch communities, wherein each of the packet switch communities has a plurality of endpoints connected to a common packet switch and having a unique address, and wherein each of the endpoints has addresses unique to their respective packet switch community. The endpoints in this system add a two-part destination address to the packetized data to be sent, wherein the first field represents a packet switch community and the second represents a destination endpoint. Each packet switch community is responsive to the first field being different from its own address for delivering the packetized data to a switch. The switch is responsive to the first field for delivering the packetized data to a packet switch community identified by the first field. Finally, each endpoint in the destination packet switch community is responsive to the first and second address fields for accepting packetized data.

Abstract: An arrangement where a switching system receives parameter(s) concerning the traffic expected on a call from a first user to a second user, the system determines a priority for the call based on the expected traffic parameter(s), and information is transmitted to the second user during the call based on the determined priority and with less than a maximum jitter. The priority is selected from a predefined priority table based on expected traffic parameters. The priority table is usable for both constant bit rate and statistical calls.

Abstract: This invention relates to a method and apparatus for controlling overload in a data network. The exemplary embodiment is a Broadband Integrated Services Digital Network (B-ISDN) in which data is transmitted within data cells included in a larger data frame using the Asynchronous Transfer Mode (ATM) protocol. In response to the network detecting overload, the network sends slow down messages to selected virtual channels to decrease their data rates. The network also acts to block or decrease resource allocations to transmission requests that are likely to overload the network.

Abstract: A shared-buffer-memory-based asynchronous transfer mode (ATM) switch module (1) is duplicated (2) and operates in active-standby mode for fault-tolerance. Following failure and repair of a module, contents of the two modules are resynchronized as follows. When the synchronizing operation is begun contents of the memory of the repaired standby module are cleared, all writes to the active module's memory are also made to the standby module's memory, and the system monitors the overwriting of the contents of the active module's memory that existed at the time the synchronizing commences. This is done by a function (FIG. 4), which sets a flat (64) in a queue-length-counter monitor (60) for every active-module queue-length counter (200) that reaches a count of zero, to indicate that its corresponding buffer-memory queue (100) has been emptied.

Abstract: A shared-buffer-memory-based ATM switching module (FIG. 1) used with ATM cells having a multiplicity of priorities has a plurality of queues (100) for each output port (O-N), one for each cell priority, and handles buffer overflow in a manner fair to all output ports. It initially allows output-port queues (100) to completely consume the buffer memory (12). Thereafter, when an additional incoming cell is received for which there is no room in the buffer memory, the lengths of all of the queues of each output port are individually summed (402) and compared to determine which port has the greatest number of buffered cells (406). A buffered ATM cell is discarded (410) from the lowest-priority non-empty queue of that port (408). The incoming cell is then stored in the memory space vacated by the discarded cell (412).

Abstract: An arrangement for switching broadband ISDN (B-ISDN) packets is disclosed. The arrangement comprises a broadband packet switch connected to B-ISDN customers and to a narrowband switch via an interface unit. B-ISDN control packets are connected by the broadband packet switch to the narrowband switch which transmits them to a control unit. The control unit responds to control messages by controlling the broadband packet switch to selectively interconnect B-ISDN customers and by controlling the broadband packet switch, the interface means and the narrowband switch to selectively interconnect B-ISDN and narrowband customers.

Abstract: A broadband packet switch arrangement comprising a broadband packet unit connected to a plurality of customer lines and a video switch for selectively connecting packetized video signals from a plurality of video sources to the customer lines. The broadband packet switch unit selectively connects customer lines and transmits received control packets received from the customer lines to a control unit which responds to video request packets by controlling the video switch to connect selected video packets to the customers lines. Each customer line includes a selector circuit which receives video packets and inter-customer broadband ISDN packets and merges them onto the customer line. After the control unit has granted permission to connect a video source to a customer line, video source change requests for the line are sent directly to the video switch which responds thereto by connecting a requested video source to the customer line.

Abstract: A network architecture of the sort-then-expand type for routing packets including destination information is disclosed. The network includes a distribution stage comprising a plurality of input sorts units, an intermediate stage comprising a plurality of intermediate sort units and an output stage comprising a plurality of output switches. The input sort units each distribute a plurality of packets to the intermediate sort units such that each intermediate sort unit receives approximately the same number of packets destined for each output switch as the other intermediate sort units. Each intermediate sort unit identifies packet groups for a common output switch and connects the groups to the destination output switch. Each destination output switch merges the received groups of packets and distributes them to output ports.