Abstract: Disclosed is an apparatus and method for granting guaranteed bandwidth between one or more data transmission priority requesting sources and one or more resources upon request. Data sources that do not request an assigned bandwidth are served on a “best efforts” basis. The system allows additional bandwidth to priority requesting sources when it is determined that the resource and/or the communication path to the resource is under-utilized. The system further allows the granted bandwidth to be shared by more than one source in a multiprocessor system.

Abstract: A system, method, and computer-readable medium for performing network system diagnostics is provided. The method includes obtaining a respective identification of a first target device and a second target device deployed in a network; iteratively querying neighbor devices of at least one node in a communications path between the first and second target devices, wherein the neighbor devices and the first and second target device may comprise heterogeneous network nodes; and generating a layer 2 path trace that comprises identification of network devices interconnected on a physical path between the first and second target devices. A computer-readable medium includes instructions for execution by a processing system, wherein the instructions are configured to perform the foregoing method. A system includes a data processing system including a processor device for executing a diagnostics engine implemented as a set of computer-executable instructions configured to perform the foregoing method.

Abstract: A method for multiplexing digital data, wherein a packet of digital data is simultaneously sent from front to rear and from rear to front. Additionally, a method for multiplexing digital data, wherein a packet of digital data is simultaneously sent from the beginning of the packet towards the end and from the end towards the beginning. Additionally, a method for multiplexing digital data, wherein simultaneously a packet of digital data is sent and the same packet is sent backwards.

Abstract: In some embodiments of the present invention, asynchronous network nodes and synchronous network nodes coexist on a shared media network.

Abstract: Transfer of data is facilitated between at least one application and a peer via a network. Data destined for the peer is provided from the at least one application for transmission to the peer via the network. Modulation event tokens are managed, and protocol processing of the data with the peer is based in part on a result of the modulation event tokens managing such that protocol processed data is caused to be transmitted to the peer via the network nominally with desired data transmission rate characteristics. A result of the protocol processing step is fed back to the to the modulation event tokens managing. The desired data transmission rate characteristics may include, for example, shaping and pacing.

Abstract: First and second serial data busses are arranged so that simultaneous transmission on the respective bus of a dominant state by one node and a recessive state by other nodes results in the dominant state being detectable on the respective bus. Transitions from a first state to a second state signal the start of a bit on the first bus. Dominant and recessive states are detected on the first and second busses at first and second predetermined times after each transition. The states represent respective dominant and recessive bits of attempted messages transmitted by nodes of the first and second busses. The dominant state is transmitted on both busses after the first and second predetermined times if the dominant state was detected on one of the first and the second busses at the first and second predetermined times.

Abstract: A computer program product for managing connections comprises a computer readable storage medium having the following computer instructions. The instructions cause a controller to perform: outputting an image including icons representing respective devices connected to an IEEE 1394 serial bus to display means; and establishing a logical connection between two of the connected devices by updating the contents of iPCR and oPCR stored in register spaces in the two connected devices and updating data for management of a band and a channel that is stored in a register space provided in an isochronous resource manager, which is a node for isochronous resource management on the IEEE 1394 serial bus, when a user enters a selection of the two connected devices to be logically connected to each other from among the connected devices on the bus.

Abstract: In the method for addressing the participants of a bus system, the central control unit connects the bus line to one potential of the operating voltage, while each participant tries to pull the bus line to a reference potential, normally the operating voltage, wherein, due to the current source behavior of the switch placing the bus to the operating voltage, a current is detectable by a detector arranged in the bus line and associated with the participant. When the participant detects this decrease of current, said participant switches off its switch. Due to time-defined slow connection of the switched current sources, this process takes place sequentially within a group of participants until the last participant is reached. The detector associated with this participant does in no case detect a current, such that, after elapse of a predeterminable on-period, the switch of this participant is still open.

Abstract: A generic software protocol allows communication between multiple devices within an electronic control system as well as between an electronic control system and an external monitoring device. The generic software protocol is reflected in embedded software in each device in the electronic control system. By using the same protocol in all of the electronic control system devices, the protocol reduces computer processing overhead while providing a predictable, yet flexible framework for device communication.

Abstract: A method and a device for exchanging data in messages between at least two stations connected by a bus system. The messages contain the data being transmitted by the stations over the bus system. Each message contains an identifier characterizing the data contained therein. Each station decides on the basis of the identifier whether to receive the message. The messages are controlled in time by a first station. The first station repeatedly transmits a reference message over the bus in at least one specifiable time interval. The time interval is subdivided into time windows of a specifiable length, the messages being transmitted in the time windows.

Abstract: A wireless station communicates with at least one other wireless station in a local area network (LAN). A media access control (MAC) device controls transitions between an active mode and a low power mode. A radio frequency (RF) transceiver communicates with the MAC device and, after the transition to the active mode, transmits data during a predetermined time slot that is assigned to the wireless LAN station and that is not assigned to other wireless LAN stations in the LAN. The RF transceiver receives data from other wireless LAN stations in the LAN during the active mode and transitions to the low power mode after receiving the data from the other wireless LAN stations. The MAC device transitions the wireless LAN station to the active mode prior to a timing beacon and transitions the wireless LAN station to the low power mode prior to a subsequent beacon.

Abstract: A radio frequency (RF) bus controller includes an interface and a processing module. The interface is coupled for communicating intra-device RF bus access requests and allocations. The processing module is coupled to receive an access request to an RF bus via the interface; determine RF bus resource availability; and when sufficient RF bus resources are available to fulfill the access request, allocate, via the interface, at least one RF bus resource in response to the access request.

Abstract: Communicating between first and second serial data busses is described. Each bus includes one or more nodes coupled via the respective data bus so that simultaneous transmission on the respective bus of a dominant state by at least one of the nodes and a recessive state by the other nodes results in the dominant state being detectable on the respective bus. Transitions from a first state to a second state are transmitted onto the first bus. The first and second states are complementary states selected from the dominant and recessive states. Each of the transitions signal the start of a bit on the first bus. Dominant and recessive states are detected on the first bus at a first predetermined time after each transition and on the second bus at a second predetermined time after each transition. The states represent respective dominant and recessive bits of attempted messages transmitted by nodes of the first and second busses.

Abstract: A communications system in which a first node is connected to a plurality of second nodes for controlling the operation of the second nodes. The plurality of second nodes is arranged in one or more logical interconnects, the topology of the one or more logical interconnects being distinct from the topology of the physical interconnection of the nodes. Each second node sends status messages to its logical successor node and monitors the status messages received from its logical predecessor node for determining the status thereof.

Abstract: The error-free function of modules in a bus system with a central unit is tested. First, all (error-free) modules are set into a silent operating mode in response to an agreed silence-command, and then in this silent operating mode it is tested whether all modules still remain silent, i.e. do not transmit data, in response to an agreed data request allocated to these modules. A module that nonetheless transmits data is recognized as faulty and is deactivated. Subsequently, all modules except for a module to be tested are set into the silent operating mode, and then it is tested whether this test module transmits its data in response to the agreed data requests allocated to it and remains silent in response to the data requests not allocated to it. Additionally, the position of the return-transmitted data can be determined and compared with a nominal position.

Abstract: The present invention provides for a method and computer program product for handling timeout in a standard RPC connection. First, a client establishes a connection with a server with unique identification. After submitting an RPC request, the client system will periodically make secondary requests to the server to determine if the server is still actively processing the primary RPC request. If the secondary request is processed successfully and the server indicates that the primary request is still in progress, the client will continue to wait until either the primary request completes or enough time elapses to warrant another secondary request. The success of the secondary request hinges on finding a match of identification for the primary and secondary requests. If the secondary request fails, this failure is treated as a sign that there is either a network or a server problem, and the client is triggered into taking appropriate corrective action.

Abstract: A method for managing an asynchronous transfer mode (ATM) cell includes transmitting an ATM cell from a server system to a broadband modem. The ATM cell is forwarded from the broadband modem to a client system.

Abstract: An intercom system utilizing peer-to-peer computer network hardware that shares bandwidth between digital audio transport and inter-processor data communications on a common time-division-multiplexed (TDM) parallel bus. The system hardware automates symmetric, simultaneous, variable-length data block transfers among all of the microprocessor-controlled cards in the system. These cards communicate without intervention by or assistance from a central controller or intermediary communications processor, thereby improving system throughput and reliability and decreasing system complexity. An additional benefit of the communication scheme employed herein is that all system cards automatically track changes in the population of other cards in the system. The intercom system described employs a Configuration Card connected to a configuration computer to provides the system supervisor with the ability to quickly configure the system for a particular use without altering the system's hardware configuration.

Abstract: A memory has a set of address spaces to which token data is written and read. Each address space has a token status bit. A token generator allocates token data to the memory address spaces. Upon a reset occurring, a logic circuit provides logic “0” to the token generator disabling status bit checking control so that all the tokens can be issued sequentially. New token data is allocated to the address spaces sequentially and the respective status bit is updated or maintained as logic “1”. When all address spaces have been allocated, the logic circuit provides the actual state of the status bit to the token generator to control subsequent allocations.

Abstract: A method for the exchange of data in messages between at least two users which are connected by a bus system, the messages containing the data being transmitted by the users via the bus system, and each user containing a predefinable and/or ascertainable timing mark; a first user, in a function as timer, controls the messages as a function of time in such a way that it repeatedly transmits a reference message, which contains time information of the first user, via the bus at a specifiable time interval, and if the timing mark of the second user is reached without a reference message of the first user reaching the second user, the at least second user takes over the function of timer by transmitting its own reference message with its own time information via the bus system.

Abstract: A communications protocol for a communications bus wherein messages are transmitted to a plurality of devices communicating by a bus. Each message includes a unique code indicating the end of the message and that same unique code triggers a transfer of communications control to another device of the plurality of devices.

Abstract: A method for matching an upper protocol layer to a high speed serial bus is provided. The method includes the steps of (a) determining whether the length of the data packet transferred from an upper layer to a node of the high speed serial bus is no less than a predetermined length, (b) allocating a channel of the bus and transferring data by an isochronous transfer service when it is determined that the length of the data packet is no less than the predetermined length, and (c) transferring data by an asynchronous transfer service when it is determined that the length of the data packet is less than the predetermined length. According to the above method, it is possible to match an existing communications application where it is not specified which service of the high speed serial bus is to be used to the high speed serial bus, while maintaining transparency of communication protocol and to effectively use the channel resources of the bus.

Abstract: A communications network having two complementary optical networks each connectable to a headend, each optical network comprising a plurality of periodic interleaving filters serially connected by optical waveguides such that an output port of one periodic interleaving filter is couple to an input port of another periodic interleaving filter, and wherein an input or output node of the network is formed by a non-serially connected input or output port of a periodic interleaving filter.

Abstract: A multiplex communication system includes a plurality of networks and a data relay unit. When an event occurs in a node belonging to one of the networks, the node (sender node) sends a wake-up frame before it sends an event frame. In response to the wake-up frame, the nodes belonging to the same network which includes the sender node are activated and the data relay unit sends a wake-up frame to the respective networks for activating the networks. When it is determined that each of the networks is activated, the data relay unit sends a network activation notifying (NAN) frame regarding the network to all the networks. The NAN frame regarding the network represents that the network is activated. The sender node sends the event frame in response to the NAN frame regarding the destination network of the event frame.

Abstract: An improved pipe belling apparatus and method are shown in which a spiral strip of thermoplastic material is extruded and wrapped spirally about a mandrel and integral gasket. The heated material is allowed to cool and the connection thus formed is stripped from the mandrel. The gasket is retained within a groove which is simultaneously formed of the thermoplastic extrusion.

Abstract: A method, apparatus, and system are provided for transmitting an Asynchronous Transfer Mode (ATM) cell from a server system to a broadband modem and forwarding the ATM cell from the broadband modem to a client system. According to one embodiment, a Broadband Modem Access Protocol (BMAP) unit is used to discover the identity of the broadband modem.

Abstract: A transmission managing apparatus included in an information transmitting system comprising a communication bus (B), an indicating device (NI), which has a transmission state memory (5) for storing a channel used for an information transmission executed in a time division manner on the communication bus and a transmission occupation period occupied for the information transmission, for indicating the channel and the transmission occupation period and an information processing apparatus (N) for reserving a non-used channel and a preservable period, while referring to a memory content of the transmission state memory.

Abstract: One embodiment of the present invention provides a system for enhancing the effective timing margins and the reliability of a digital system bus. The system monitors the digital system bus to determine the data flow between devices on the digital system bus. If an absence of data flow is detected, the system generates a pseudo-data signal to replace the normal data signal on the digital system bus. This pseudo-data signal is broadcast on the digital system bus, in order to keep the digital system bus active, thereby preventing subsequent transmissions from suffering from effects caused by an inactive digital system bus.

Abstract: Methods and apparatus used in systems for communicating data (e.g., voice, video and alphanumeric data), including but not limited to telecommunications systems, computer systems, to efficiently utilize bandwidth by performing bit sensitive peer addressing. Apparatus (and related methods) for performing bit sensitive peer addressing include a parallel bus of data bits, a clock bit, a bid/busy bit, and an ack bit. The invention further includes a plurality of port devices coupled to the bus. Each port device includes bus interface circuitry, port control circuitry, and line interface circuitry. The clock signal is used to synchronize messages on the bus and to divide the time domain into timeslots (one timeslot being the reciprocal of the clock frequency). According to the invention, no frame reference is used and traffic on the bus is controlled using a protocol. Each port has an address which is one of the data bits of the bus.

Abstract: In a system including multiple enclosures, unique enclosure addresses can be set automatically via software. The enclosure addresses may be stored in non-volatile memory within the enclosures. In a storage system, several enclosures contain several disk drives, wherein each disk drive requires a unique device address related to the enclosure in which it resides. A unique address is automatically assigned via software to each enclosure.

Abstract: According to the invention, impact sensors are repeatedly interrogated during a polling mode and have to actively reply by emitting current pulses. If a sensor does not reply it is selectively addressed and can at that point signal a desired message. The master unit has full communications control over the bus so that data collisions can be avoided and very rapid transmission of the sensor signal is achieved. The master unit can change the communication priorities at any time.

Abstract: A communications bus management circuit for a current probe system detects the connection of the current probe system to an instrument and the connection of a current probe to a current probe amplifier of the system. A controller generates a probe enable signal in the presence of the detected connection to the instrument that is coupled to a switching circuit. Switch elements couple the communications bus of the instrument to the communications bus of the current probe amplifier in the presence of the probe enable signal. The controller further generates a current probe present signal in the presence of the detected current probe that is also coupled to the switching element. A further switch element couples the data line of the instrument to ground via a resistive element in the presence of the current probe present signal and floats the data line when the current probe present signal is absent.

Abstract: A SONET network interface for interconnecting at least one high speed unit (HSU) with at least two low speed interface units (LSUs) to enable transmission of signals therebetween. The interface having: a common bus of predetermined bit width for interfacing the HSU unit with each of the LSU units to enable transmission of signals from each of the LSUs to the HSU, and reception of the signals from the HSU to each of the LSUs; a first partition bus of the predetermined bit width for interfacing the HSU to a predetermined number of the LSUs, the first partition bus being partitioned into a first bus for interfacing the HSU to a first subset of the LSUs and a second bus for interfacing the HSU to a second subset of the LSUs; and a second partition bus of the predetermined bit width for interfacing the HSU to a predetermined number of the LSU units.

Abstract: In a security system that has a large number of individually-addressable modules interconnected on a data bus to a control panel, a method of concurrently supervising the modules by first configuring each module with a unique zone number including a group number and a module number. During operation, the control panel initiates a group supervision poll sequence for each group number by transmitting a group poll command including a group number data field populated by the group number currently being polled. If a module is part of the group being polled, then it sets a discrete bit appended to a group poll response message that logically corresponds to the module number for that module. The control panel then determines if any bit in the group poll response message has not been set, and then issues a unit poll sequence addressed to a module that corresponds to any such bit not determined to have been set in the group poll response message.

Abstract: An information transmitting apparatus (such as player) is provided for transmitting information (audio data, video data, or others) to a plurality of information receiving apparatuses (such as receivers) via a serial bus. The transmitting apparatus has a selection unit to select one or more ones from the plurality of information receiving apparatuses and a transmission path establishing unit to establish a transmission path to the selected information receiving apparatus so that the information is transmitted therethrough. The operations required for transmission of the information can be simplified.

Abstract: In an electronic system for the transmission of data between a number of stations, sub-system operation can be achieved by a suitable choice of signal levels and wake-up levels, so that some of the stations can communicate with one another while other stations are in a sleep mode in which power is saved.

Abstract: A SONET network interface for interconnecting a high speed unit (HSU) with low speed interface units (LSUs) to enable transmission of signals therebetween. The interface including: a bus for interfacing the HSU with each of the LSU units to enable transmission of signals from each of LSUs to the HSU, and reception of the signals from the HSU to each of the LSUs; and a backplane connected to the bus and having at least two time slots for performing full time slot interchange between the at least two LSUs, wherein any of the at least two LSUs can read received data directly from one of the at least two time slots and can place its transmit data into any other of the at least two time slots for communication with another of the at least two LSUs without exchanging the received and/or transmit data with the at least one HSU.

Abstract: A retransmission value in a digital cellular phone is negotiated using information from the cellular phone, sent to the network.

Abstract: A real time device polling method for multiplexed transmission of on/off constant bit rate data, such as voice data from a telephone call, over a cable data network is disclosed. The network serves as a shared bus for both the downstream and upstream traffic. The upstream channel is modeled as a stream of mini-slots. A cable modem termination system at the head end supports a number of cable modems attached to the cable network and connected to customer premises equipment. Allocation maps are transmitted on the downstream channel to the cable modems to define transmission opportunities on the upstream channel. The cable modem termination system polls the cable modems in an efficient way such that the overhead associated with the polling is minimized, and the availability of data transmission slots is synchronized with the data packet generation by the codec for the cable modem, which minimizes delay.

Abstract: In some embodiments of the present invention, asynchronous network nodes and synchronous network nodes coexist on a shared media network.

Abstract: A distributed conferencing system having a plurality of conferencing nodes to connect groups of participants to a conference. Each of the conferencing nodes provides for the connection of one or more participants to the conference. Each node includes a DSP for distributed signal processing. The node DSP includes: A signal measuring device for measuring features of the signals from each of the participants, such as power, zero crossing rate and short term energy and voice activity determination and feature extraction from the signals of the participants connected to each node. Each node has a single core speaker tracking algorithm for determining the relative features of each of the number of participant input signals. The speaker tracking compares the characteristics of the speakers of the core and determines which speakers are to be included and which speakers are to be excluded from presentation to the other nodes in the conference.

Abstract: The invention relates to a device for acquisition of measurements using a digital communication bus (10) and a computer system, comprising:

Abstract: Apparatus for simultaneously transferring synchronous and asynchronous signals among broadband access devices includes a data bus, a clock bus, and a plurality of control lines which are used to indicate the type of data being carried on the bus. According to the methods of the invention, data is transferred on the bus in a repeating frame having a plurality of slots, each slot being defined as one bus clock cycle. Each slot may contain a synchronous or asynchronous data signal and one or more of the control lines are asserted during the slot time of the data to indicate the type of data. Two embodiments are provided. One utilizes a 25 MHz clock bus and a repeating frame of three hundred thirty-six slots. The other utilizes a 75 MHz clock bus and a repeating frame of one thousand eight slots.

Abstract: An asynchronous data pipe (ADP) automatically generates transactions necessary to complete asynchronous data transfer operations for an application over a bus structure. The ADP includes a register file which is programmed and initiated by the application. The register file includes the bus speed, transaction label, transaction code, destination node identifier, destination offset address, length of each data packet, packet counter, packet counter bump field, control field and a status field. During a data transfer operation, the ADP generates the transactions necessary to complete the operation over the appropriate range of addresses, using the information in the register file as a template. The ADP increments the value in the destination offset address field for each transaction according to the length of each data packet, unless the incrementing feature has been disabled and the transactions are to take place at a fixed address.

Abstract: A communication technique capable of flexibly using traffic between packets requiring a real-time service and packets not requiring that service. A main transmission channel 11 is time-division-controlled, and terminals respectively assigned divided time slots 51-54 transmit packets 21-24 using as much portions of time slots as needed to free the remaining portions of time slots. Other terminals share the remaining portions of time slots according to a contention type protocol to transmit packets 31-36.

Abstract: A method and apparatus for processing data packets through direct memory access (DMA) in transferring data packets between a bus and an apparatus containing DMA engines. The DMA engines process different contexts, also referred to as distinct logical data streams. The phase of a bus along with the status of DMA transactions are monitored. The phase and the status are used to dynamically allocate priorities to the DMA engines to maximize the efficiency in processing data.

Abstract: The invention provides a method and apparatus for end-users to allocate a communication medium locally without requiring a central arbitration device while guaranteeing access to the end-users. The end-users bid for control of an upstream data channel by concurrently transmitting auction data and address data on a first upstream signaling channel and a second upstream signaling channel. An end-user gains control of the upstream data channel when data received from the first and second downstream signaling channels match the auction and address bits. When it is determined that the end-user lost the bid, the end-user backs off from the first and second upstream signaling channels and refrains from bidding until the first and second upstream signaling channels become quiet.

Abstract: A circuit for detecting whether an intermittent clock waveform signal of 50 MHz is received or not includes an offset receiver, a charge pump, a capacitor and a hysteresis comparator. A circuit for detecting whether a random data waveform signal of 500 MHz is received or not includes an offset-less receiver, a transition counter, a delay circuit and an AND circuit. An OR circuit outputs as a signal detection signal a signal indicating the OR operation result of respective outputs of the hysteresis comparator and the AND circuit.

Abstract: A multiplex communications system includes a plurality of master-slave sub-systems which include master nodes (10, 20) connected to a multiplex communications line (BL) and slave nodes (30, 40, 50) connected to the same. Each master node transmits a signal to the slave node of the same sub-system at a first given cycle, and in response the slave node transmits a signal, thereby establishing communication between the master node and the slave node. If periodic transmission of a signal at the first given cycle is not correctly carried out, the master node, which correctly performs periodic transmission of a signal, periodically transmits a signal to both the slave nodes at a second given cycle which is slightly longer than the first given cycle.

Abstract: An enhanced crosspoint bus control protocol is provided for expanding a conventional crosspoint bus by altering one or more bit definitions in a standard encoded bus control message. In accordance with one aspect of the present invention, by changing the definition of one or more predetermined bits in a message sequence such that these bits are control bits, the novel crosspoint bus control protocol preferably signifies whether the message corresponds to a standard crosspoint bus architecture or to an extended crosspoint bus architecture. The unique enhanced crosspoint bus protocol of the present invention supports an extended message length while being backward compatible with existing crosspoint bus protocols, thereby allowing the existing and enhanced crosspoint bus protocols to advantageously co-exist on the same physical bus.