Patents Examined by T. Samuel
  • Patent number: 5311461
    Abstract: In a computer system in which conflicting requests for resources are prioritized, a programmable priority determination method and system. Relative priority between competing sources or requests is represented by a control word (priority code). The control word includes bits identifying the highest priority source, and rotation and skip bits determining the order or priority among the other sources. The control word is used to pre-set a priority circuit which then selects from among competing resource requests based on the priority represented by the control word. Relative priority between the sources can be changed during operation of the computer system by creating a new control word and applying it to the priority circuit.
    Type: Grant
    Filed: December 30, 1988
    Date of Patent: May 10, 1994
    Assignee: International Business Machines Corp.
    Inventor: Patrick W. Gallagher
  • Patent number: 5245607
    Abstract: A facility is provided in a data network to prevent a so-called connectionless broadcast message from flooding the network as a result of each network node retransmitting such messages to its neighboring nodes even though a neighboring node may have received them from another neighbor. Specifically, a node x that receives a connectionless broadcast message retransmits the message to a neighboring node y only when node x finds that it is closer to the source of the message than node y is including any other neighbor of node y.
    Type: Grant
    Filed: March 5, 1990
    Date of Patent: September 14, 1993
    Assignee: AT&T Bell Laboratories
    Inventor: Bruce E. Caram
  • Patent number: 5231632
    Abstract: In radio communication equipment for use in a mobile station, provision is made for selectively applying either one of the oscillation outputs of first and second local oscillators to a transmitting part and a receiving part by first and second RF switches, respectively. In a traffic channel hand-off system for a mobile communication system in which each time the mobile station moves from a certain zone to another, its traffic channel is switched to another traffic channel of a different frequency, a control part responds to a traffic channel assigning signal from the current base station to allot an idle one of the local oscillators to the assigned channel, set the allotted local oscillator to an oscillation frequency corresponding to the assigned channel, and control the second RF switch, in an idle time of the receiving part in the current communication, to set the receiving part to the assigned channel for receiving a down link hand-off preparatory signal from a new base station.
    Type: Grant
    Filed: November 23, 1990
    Date of Patent: July 27, 1993
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Yasushi Yamao, Yoshiaki Tarusawa, Toshio Nojima
  • Patent number: 5208806
    Abstract: ISDN terminal equipment containing: a circuit switching communication unit, a packet communication unit, a manual starting unit, an unsuccessful try detecting unit, and a retrying unit. The manual starting unit starts an operation of a setting up of a call using a predetermined one of the circuit switching communication unit and the packet communication unit when receiving a manual start input. The unsuccessful try detecting unit detects that data communication has not been successfully begun by the operation of the manual starting unit. The retrying unit starts an operation of a setting up of a call using the other of the circuit switching communication unit and the packet communication unit when the unsuccessful try detecting unit detects that the data communication has not been successfully begun by the operation of the manual starting unit.
    Type: Grant
    Filed: November 16, 1990
    Date of Patent: May 4, 1993
    Assignee: Fujitsu Limited
    Inventor: Kenichi Hasegawa
  • Patent number: 5204859
    Abstract: A method and apparatus is provided for detecting a frame alignment word in a data stream. The apparatus comprises a storage circuit (9) arranged to receive a data stream and pass each bit of the data stream serially through each location of the storage circuit. A template pattern means (10), arranged to generate a template pattern, is connected to the storage circuit (9) and arranged in bit groups, each group generating an output signal when it identifies a group of bits corresponding to its template pattern. A decoder circuit (B) is arranged to receive the output signals from the groups and generate a decoder output signal when a specified number of groups match the template pattern indicating that the frame alignment word has been detected.
    Type: Grant
    Filed: February 13, 1991
    Date of Patent: April 20, 1993
    Assignee: GEC Plessey Telecommunications Limited
    Inventors: Martin R. A. Paesler, Sover W. S. Wong
  • Patent number: 5199029
    Abstract: A circuit arrangement for establishing conference connections comprising conference units is described, which units are linked to form a loop (L). In this loop (L) sum codewords consisting of sample values of the signals of all participants in a conference are transmitted from one conference unit to the next. In each conference unit a sum codeword is updated so that the sample value of a conference signal from the previous loop travel is replaced by the current sample value. In order to enable the monotoring of a travel of sum codewords through the loop with a circuit arrangement of this type and in order to have the sum codewords pass through the loop in a predetermined brief period of time without a necessity for a synchronization of individual processing modules of the conference units, the function of one or more conference units is taken over by a programmed processor (P1 to P4). The exchange of data between the conferees and the processors is controlled by means of an interface circuit (PO).
    Type: Grant
    Filed: November 26, 1990
    Date of Patent: March 30, 1993
    Assignee: U.S. Philips Corporation
    Inventors: Peter Hessler, Manfred Schmidt, Bernd Selbach
  • Patent number: 5197067
    Abstract: Data flow control applied to a packet communication system including data terminal equipment (DTE), a first MODEM connected to one of the DTEs, a telephone switching nework (TSN) connected to the first MODEM, a packet switching network (PSN) having an assembly and disassembly equipment (PAD) and a second MODEM connected to PAD and provided between PAD and TSN and carried out by using MODEM control signals, logic signal "1" and "0", and control characters, DC1 and DC3, is performed: discriminating a designated response signal, /REL in CONNECT from a header of data transferred through the first and second MODEMs each having a buffer memory used for error correction of the data. In addition the MODEM control signals are made effective and the control characters are made ineffective and are controlled when the designated response signal is detected.
    Type: Grant
    Filed: May 4, 1992
    Date of Patent: March 23, 1993
    Assignee: Fujitsu Limited
    Inventors: Akio Fujimoto, Nobuo Shirai
  • Patent number: 5197063
    Abstract: A circuit switching apparatus and method for time division network with various transmission speeds for time-division multiplexing a plurality of circuits including signals at different transmission speeds, transmitting the same onto an input highway, repeatedly recording the transmitted signals in a data memory in a predetermined order, reading respective recorded signals in a predetermined order onto an output highway. An access unit for reading signals from the data memory has an address control memory for storing circuit switching information, a circuit speed control memory for storing transmission speed information for the respective circuits and an address generating section for generating an address for accessing the data memory on the basis of the circuit switching information and the circuit transmission speed information from those memories.
    Type: Grant
    Filed: January 16, 1991
    Date of Patent: March 23, 1993
    Assignees: Hitachi, Ltd., Nippon Telegraph and Telephone Corporation
    Inventors: Yukio Nakano, Tadayuki Kanno, Masahiro Takatori, Hiromi Ueda
  • Patent number: 5197068
    Abstract: A method of providimg two-way communication between a plurality of channel units in a channel bank and a line interface circuit of a telephone system utilizing a receive direction protocol and a separate transmit direction protocol. The receive direction protocol identifies the channel unit to which provisioning data is to be delivered, increases the bandwidth of the voice data region in the time slot corresponding to the identified channel unit, superposes the provisioning data in the time slot with the voice data, and delivers the superposed data to the channel unit wherein the provisioning data is separated from the voice data. The transmit direction protocol utilizes the A and B signaling bits corresponding to the eighth bit of an identified time slot in the sixth and twelfth transmit frames wherein two bits of an eight bit status message is delivered on every other superframe. The two-way communication protocols occur without affecting or interfering with the PCM voice data.
    Type: Grant
    Filed: August 23, 1990
    Date of Patent: March 23, 1993
    Assignee: XEL Communications, Inc.
    Inventors: David L. Holien, Joseph M. Elder, David J. Farrell
  • Patent number: 5195085
    Abstract: In a communications system having components which are interconnected via communications links, the system is provided with capability of responding to the application of a predetermined test signal to a link with information which identifies that link. Such information can take a variety of forms including the name of one or more persons assigned to use the link, and/or the telephone number or numbers associated with the link. This capability greatly reduces the time and expense associated with the maintenance and testing of a variety of communications systems, such as PBXs and central office switching machines.
    Type: Grant
    Filed: September 11, 1990
    Date of Patent: March 16, 1993
    Assignee: AT&T Bell Laboratories
    Inventors: Charles J. Bertsch, John T. Biggs
  • Patent number: 5193090
    Abstract: Access protection and priority control is performed in a network with distributed queueing by the use of counters and a memory. The counters accumulate a number of passing request bits, the number of packets waiting in a queue, request bits generated, busy bits changed by station, and the numbers of free packets which have passed the station on the communication medium. These request bits indicate that another station wishes to issue a data packet. The counters decrement when a free cell passes the station. The counters indicate a queue placing. The memory stores upper and lower threshold values. These threshold values are compared to the counter values to control the issuing of data packets from each station onto the medium. The imposed thresholds ensure that the bandwidth available to each station is maintained despite traffic load conditions, transmission rates, or length of the medium. This mechanism is applicable to the static and dynamic control of bandwidth usage of stations and nodes used in the I.E.
    Type: Grant
    Filed: June 22, 1990
    Date of Patent: March 9, 1993
    Inventors: Janusz Filipiak, Leslie T. Berry, James Gordon
  • Patent number: 5191579
    Abstract: A ring network switching apparatus connects a plurality of communication nodes by a duplex ring type transmission line. Respective communication nodes autonomously vary respective connection state by respective transmission line switching means based on the control data received from the control data receiving unit. Respective communication nodes transmit the control information designating a new transmission line state from the control information transmission unit. Thereby, respective communication nodes autonomously recover its failure and perform a re-construction of a network without an aid of a parent station. Further, the transmission data from the communication node is outputted to both transmission lines through a hybrid output section. Thus, respective communication nodes merely observe the state of the transmission line on the receiving side and switch the receiving switching means based on the observation.
    Type: Grant
    Filed: June 18, 1990
    Date of Patent: March 2, 1993
    Assignee: Fujitsu Limited
    Inventors: Akihiro Matsushita, Shinya Takemura, Toshio Watanabe, Shigeo Sakai, Nobuo Fukuda
  • Patent number: 5189667
    Abstract: In a call set-up control operation used for a data packet communication network, a call set-up controlling method comprises the steps of: preparing a plurality of call set-up algorithms different from each other; and, selecting one of the call set-up algorithms suitable for a call set-up demand, depending upon at least a load condition of the packet data communication network, whereby the call set-up operation is carried out in accordance with the selected call set-up algorithm.
    Type: Grant
    Filed: January 10, 1991
    Date of Patent: February 23, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Esaki, Takashi Kamitake
  • Patent number: 5189670
    Abstract: Data packets of mutually equal durations are transmitted from a plurality of substations to a main station via one or more transmission channels. The main station transmits on each transmission channel a synchronizing signal which indicates the beginning of a frame. A programmable memory stores maximum link establishment and maximum link disetablishment times which are characteristic of the transmission channel from the substations to the main station. The substations each comprise a programmable memory for storing the maximum establishment times and disestablishment times. On reception of the synchronizing signal on a transmission channel the substation subdivides the frame into a number of consecutive time slots of mutually equal durations at least equal to the sum of the duration of a data packet, and the stored maximum establishment and disestablishment times of that transmission channel.
    Type: Grant
    Filed: January 28, 1991
    Date of Patent: February 23, 1993
    Assignee: U.S. Philips Corporation
    Inventor: Andrew Inglis
  • Patent number: 5185739
    Abstract: In a TDMA cellular system, there is provided a mechanism for splitting the allocation of time slots within a TDM frame between adjacent coverage areas. There is provided a method of and apparatus for time-allocation of TDMA channels. It comprises: periodically allocating some portion of a carrier of radio traffic to one coverage area during one time interval and periodially allocating some other portion of that same carrier to another coverage area during a substantially non-overlapping time interval, all in time synchronism with any proximal reuse of that carrier. The distribution of channels in adjacent coverage areas thereby approaches parity and the minimum channel capacity per coverage area is enchanced.
    Type: Grant
    Filed: February 27, 1990
    Date of Patent: February 9, 1993
    Assignee: Motorola, Inc.
    Inventor: Stephen L. Spear
  • Patent number: 5182744
    Abstract: A restoration system is provided for enhancing the reliability of a telecommunications network such that particular traffic which is disrupted by, for example, a faulty link, may be quickly rerouted via an alternate route established "on the fly". In particular, each node and link forming the network is monitored, and in the event that such monitoring detects a faulty link or node then a central controller is notified. The controller is arranged to locate spare capacity and establish an alternate route, in which the continuity of the alternate route is confirmed before the disrupted traffic is transferred thereto.
    Type: Grant
    Filed: January 3, 1991
    Date of Patent: January 26, 1993
    Assignee: AT&T Bell Laboratories
    Inventors: James D. Askew, Chin-Wang Chao, David R. Cochran, Peter M. Dollard, Hossein Eslambolchi, William E. Goodson, Robert P. Guenther, Omar M. Mansour, Liem T. Nguyen, Sarma S. Tanuku
  • Patent number: 5179552
    Abstract: A crosspoint matrix switching element and associated method for a large (e.g. approximately 1 Terabit/second) packet switch (200) or a non-buffer based statistical multiplexor (1810), using a crossbar matrix network in which, first, the output ports of individual switching elements (e.g. 1340.sub.1,1, 1340.sub.2,1) are partitioned into various groups (e.g. 1110) in order to share routing paths (links) (e.g. 1115.sub.1, 1115.sub.2, . . . , 1115.sub.K) among the elements in any such group and, second, the outputs of each such group are themselves recursively partitioned into a succession of serially connected groups (e.g. 1140, 1160) that each provides a decreasing number of outputs until one such output is provided for each corresponding output port (278.sub.1, 278.sub.2, . . . , 278.sub.N) of the switch.
    Type: Grant
    Filed: January 10, 1992
    Date of Patent: January 12, 1993
    Assignee: Bell Communications Research, Inc.
    Inventor: Hung-Hsiang J. Chao
  • Patent number: 5179555
    Abstract: A bridge/router for use in bridging and routing data among one or more local area networks and a wide area network is disclosed. The bridge/router utilizes a data compressor adapted to compress data in frames adding an end of compression marker after each frame. The bridge/router provides data transmission speeds as fast as 2.048 Mbps and includes means for inhibiting the end of compression marker, while generating a data structure with each frame which is compressed with the frame of data. The data structure includes information representing the number of bytes of raw data in the corresponding frame so that on decompression the decompresser knows the number of bytes to provide in the resulting frame of decompressed data, thus avoiding the need for the end of compression marker. By inhibiting the marker compression is performed with greater efficiency.
    Type: Grant
    Filed: January 21, 1992
    Date of Patent: January 12, 1993
    Assignee: Microcom Systems, Inc.
    Inventors: Gary Videlock, Mark J. Freitas, Philip P. Gailinas
  • Patent number: 5177679
    Abstract: This invention provides an instruction-driven, bit stream sequencer for digital computers that uses a reduced instruction set with as few as four instructions. The sequencer receives a sequence of M-bit control words; and each control word consists of an m.sub.1 -bit flag select word that selects an input or output line (out of a population of up to 2.sup.m.sbsp.1 lines) and an m.sub.2 -bit op code word that selects from among a population of 2.sup.m.sbsp.2 instructions, with m.sub.1 +m.sub.2 =M. The sequencer uses two one-bit registers and a logic function unit. One register receives a bit from the input port of the sequencer and passes the bit to the logic function unit. The second register, which holds a bit representing the present state of the processing, also passes this bit to the logic function unit for formation of a logical function or command based on these two bits; the second register also serves as the source of bits for the output lines of the sequencer.
    Type: Grant
    Filed: December 29, 1988
    Date of Patent: January 5, 1993
    Assignee: Advanced Micro Devices Inc.
    Inventor: Michael A. Baxter
  • Patent number: 5177735
    Abstract: The invention concerns private telephone instalations, in particular key systems or small time-division switches, each provided with a central unit (2) including a time-division digital switching network (3) controlled by a control unit (4) to enable communication of a pluality of telephone or terminals (1) either directly by means of the switching network or by means of telephone lines (32) terminating at a local central office, the telephones or terminals or lines being connected to termination circuits (30, 31) which connect them to the switching network (3) via at least one time-division multiplex link (12) and to the control unit (4). A two-wire bidirectional signalling link (13) is time-shared between all the termination circuits for interchanges of signaling with the control unit (4); it is connected direct to a series-parallel converter circuit (8).
    Type: Grant
    Filed: June 19, 1990
    Date of Patent: January 5, 1993
    Assignee: Alcatel Business Systems
    Inventors: Raymond Blaszykowski, Robert Girard, Andre Bonvallet