Distributed Switching Patents (Class 370/396)
  • Patent number: 6115756
    Abstract: A computer system employs a hierarchical ring structure for communication. Computer system elements are configured into modules with ring interface hardware, and the modules are coupled to one or more rings. Bridge modules may be included for transmitting between rings in the hierarchy. The rings are time division multiplexed, and each time slot on a ring carries a frame. According to an address carried within the frame, bridge modules determine whether or not to transmit a frame circulating on a source ring onto a target ring. If the address of the frame indicates a module upon the source ring, the bridge module retransmits the frame on the source ring. Otherwise, the bridge module transmits the frame on the target ring. The bridge module operates in this fashion at any level of the hierarchy. The owner of a time slot on a ring is permitted to release the time slot for use by other modules. To reclaim a time slot, the owner marks the time slot owned.
    Type: Grant
    Filed: June 27, 1997
    Date of Patent: September 5, 2000
    Assignee: Sun Microsystems, Inc.
    Inventor: Bodo K. Parady
  • Patent number: 6111858
    Abstract: An ATM subnetwork, suitable for a low-cost home area network, comprises an interconnected mesh of simple ATM switches, end stations and multi-access buses implemented in fully-hardware configurations. Software for signalling and management functions does not reside in these devices, but rather is banished to computers outside the interconnected mesh. Specifically, an external controller acts a proxy for the simple ATM switches and performs all virtual channel connection set-up within the interconnected mesh. Additionally, proxy controllers manage each simple end station and proxy signalling agents permit standard ATM devices to be connected to the simple switches. These proxy processes communicate with the devices within the interconnected mesh via a control protocol of single cell messages delivered over dedicated permanent virtual circuits.
    Type: Grant
    Filed: February 18, 1997
    Date of Patent: August 29, 2000
    Assignee: Virata Limited
    Inventors: David J. Greaves, Richard J. Bradbury
  • Patent number: 6108337
    Abstract: A resource manager for managing the resources of a virtual bearer channel platform. The platform includes a plurality of transaction processing units (TPUs). Each TPU processes service requests transmitted by a caller or transmits service requests to a destination called party. The platform has a distribution network that interfaces with the TPUs and acts as a shared bus between the TPUs. The platform receives and transmits communications with a communications network over bearer channels of a high bandwidth pipe. A cross-connecting controller multiplexes the signals coming into the platform over the bearer channels onto the distribution network, and also demultiplexes signals going out over the bearer channels from the distribution network. The resource manager provides a centralized control for the allocation of bandwidth to the transaction processing units.
    Type: Grant
    Filed: January 7, 1998
    Date of Patent: August 22, 2000
    Assignee: MCI WorldCom, Inc. Technology Department
    Inventors: Frederick A. Sherman, Ranga R. Dendi, Timothy A. Morgan, Robert Gary Leonard, Duke Bond
  • Patent number: 6104699
    Abstract: A method and device partition physical transmission resources of a physical network. At first, a set of logical networks is established on top of the physical network. The logical networks comprise nodes and logical links extending between the nodes so as to form the logical networks. The logical links are used by routes. Next, the capacities of the logical links of the logical networks are determined such that the route blocking probability on each individual route in each one of the logical networks is less than or equal to a maximum allowed blocking probability for each individual route. This is realized by distributing, for each individual route, the route blocking evenly among the logical links used by the individual route. Finally, the physical transmission resources are allocated among the logical links of the logical networks according to the determination.
    Type: Grant
    Filed: April 29, 1997
    Date of Patent: August 15, 2000
    Assignee: Telefonaktiebolget LM Ericsson
    Inventors: Wlodek Holender, deceased, Tamas Henk, Soren Blaabjerg, Andras Farago, Bengt Stavenow
  • Patent number: 6104714
    Abstract: A method and apparatus for an isochronous traffic of Asynchronous Transfer Mode (ATM) cells in a ring network having at least two stations (101,102) and a ring server (001). The communication within the ring is based on specific isochronous control and data cells. The control cell contains a cell header, sequence number, type of command and parameter fields. The data cell contains a header and a payload divided into N m-bit slots. The isochronous data cells are shared by a plurality of stations on the ring by allocating corresponding slotlist whose identification is carried in the parameter field. Furthermore, the server provides for each station's communication link a transmit identifier in the header associated to a reference in a list of allocated slots for transmission and a receive identifier associated to a reference in a list of allocated slots for reception.
    Type: Grant
    Filed: September 17, 1997
    Date of Patent: August 15, 2000
    Assignee: International Business Machines Corporation
    Inventors: Francis Baudelot, Alain Benayoun, Jean-Fracois LePennec, Patrick Michel
  • Patent number: 6101187
    Abstract: A protocol adapter for an Asynchronous Transfer Mode (ATM) cell switching system has a receive part and a transmit part, the receive part being arranged to convert an incoming ATM cell into a cell structured with a payload and a header including an output index (OI). The transmit part is arranged to convert the structured cell after it is routed through the switching system into an ATM cell, and to output the ATM cell on the ATM communication lines. The transmit part has cell processing logic for adding a bit (mother-bit) in the header of each incoming structured The output index of a mother cell is used to access a location in a look-up table which contains for each output index, a multicast bit for indicating whether the cell is to be multicasted or not, a queue index for indicating a location where to enqueue the cell before it is outputted from the transmit part, a new VP/VC/Li value for constructing a new header, and a next-output index.
    Type: Grant
    Filed: December 10, 1997
    Date of Patent: August 8, 2000
    Assignee: International Business Machines Corporation
    Inventors: Maurice Cukier, Michel Poret, Jocelyne Jaumes
  • Patent number: 6097718
    Abstract: A method and system for maintaining and updating routing information in a packet switching network for a set of quasidynamic routes, in which intermittent routing updates are permitted, so that routes are no longer "always static" or "always dynamic", but may change over time between static and dynamic, and are treated accordingly. The invention is particularly applicable to dial-on-demand serial communication links, but is also useful in any situation where it is desired to reduce the overhead from routing updates over a communication link, or where transmission over a communication link is not reliable. A protocol manager for a dynamic routing protocol is modified to determine, for each route, (1) whether to send updated routing information for that route (at the time it would otherwise send an up-date for a particular route), and (2) whether to age that route in its routing tables (at the time it would otherwise age that route).
    Type: Grant
    Filed: January 2, 1996
    Date of Patent: August 1, 2000
    Assignee: Cisco Technology, Inc.
    Inventor: Joel P. Bion
  • Patent number: 6092096
    Abstract: The Data communication systems and methods in which information for routing of messages between nodes of a communications network is provided by a directory service (such as the DCE directory service), accessible from all network nodes. The provision of such information by the directory service removes the requirement for routing tables to be set up and maintained at each of the network nodes, whose maintenance can involve considerable network traffic in dynamically changing networks or problems of inconsistent data being held at different nodes.
    Type: Grant
    Filed: May 30, 1997
    Date of Patent: July 18, 2000
    Assignee: International Business Machines Corporation
    Inventor: Jonathan Rhys Lewis
  • Patent number: 6081836
    Abstract: Method for the transmission of information packets between a source LEC of a first ELAN and a destination LEC of a second ELAN, having the following method steps: determination of the destination ATM address by transmission of an address resolution request of the source LEC to the second ELAN via a CLS wideare network offering a connectionless service and resolution of the destination MAC address in the second ELAN into the appertaining ATM address; initiation of a connection setup between source LEC and destination LEC via an ATM network ranking higher than the first ELAN and the second ELAN upon employment of the identified destination ATM address; and transmission of the information packets via the higher-ranking ATM network. In one exemplary embodiment, the determined ATM address is transmitted to the first ELAN via the CLS wide-area network as address resolution response and is transmitted thereat to the source LEC, and the source LEC initiates a connection setup to the destination LEC.
    Type: Grant
    Filed: December 22, 1997
    Date of Patent: June 27, 2000
    Assignee: Siemens Aktiengesellschaft
    Inventors: Stefan Karapetkov, Ingrid Fromm, Bernhard Petri
  • Patent number: 6076094
    Abstract: A method for broadcasting data to a television set using a carrier signal such as a television or commercial radio carrier signal composed of the steps of: constructing a data stream from individual first record of a transmission database, each first record comprising one of a selection of formats, at least one of the first records comprising executable program code or an object, broadcasting the data stream within the carrier signal, providing a user with a user's device for receiving and decoding the data stream, the user's device receiving and decoding the data stream to a user's database, the user's database having second records comprising at least some of the first records, the second records comprising one of a selection of formats and at least one record comprising executable program code or an object broadcast from the first records determining the format a second record using a control program running, when required, the executable program code, and generating a display on the television consistent
    Type: Grant
    Filed: May 21, 1999
    Date of Patent: June 13, 2000
    Assignee: Io Research Pty. Limited
    Inventors: Thomas Andrew Cohen, Robert Jeffries Chatfield
  • Patent number: 6067654
    Abstract: An ATM switch including ECC encoder circuits each for generating, for an ATM cell as an information symbol, an ECC check symbol and for adding the ECC check symbol thereto, cell partitioning circuits each for subdividing an information field of an ATM cell into N partial cells, for subdividing a check symbol field into M partial cells, and for assigning an identical routing tag to the obtained partial cells (N+M) partial cell switches for respectively routing the (N+M) partial cells in an independent fashion based on the routing tag, and ECC decoder circuits for receiving the (N+M) partial cells thus routed and for achieving an error correction on the received partial cells.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: May 23, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Nakano, Takahiko Kozaki, Shinobu Gohara, Yoshihiro Ashi
  • Patent number: 6055237
    Abstract: A telephone switching system comprises a plurality of switching nodes interconnected by a call-switching network. The switching nodes are also linked by a host network to one or more hosts that exercise supervisory control over the nodes. The hosts communicate directly with one or more of the nodes, termed "switching nodes", by means of virtual connections over the host network. The other switching nodes, termed "slave nodes", are assigned to host nodes. The hosts communicate indirectly with the slave nodes by way of switching nodes to which they are assigned. Communications between a host and a slave node thus comprise messages (a) over the host network between the slave node and the switching node to which the slave node is assigned and (b) by way of a virtual connection between the switching node and the host.
    Type: Grant
    Filed: March 3, 1997
    Date of Patent: April 25, 2000
    Assignee: Excel Switching Corporation
    Inventors: Mark P. Hebert, Peter Higgins
  • Patent number: 6052372
    Abstract: Communications are established between a source user (305) and a destination user (307). Data is transmitted between these users in packets (204) having a destination address (205) and communication data (206). A destination name is identified in a first packet and this packet is transmitted to a service control platform (301) identifying, in its communication data, a destination name. A packet is then returned from the control platform (301) to the originating source (305) identifying a real contactable address for the identified destination (307). Subsequent packets of data are generated at the source (305) for transmission to the destination (307) wherein the transmitted packets have the actual destination address, as returned from the service platform, appended thereto.
    Type: Grant
    Filed: November 7, 1996
    Date of Patent: April 18, 2000
    Assignee: British Telecommunications public limited company
    Inventors: Christopher J. Gittins, Stephan Harris
  • Patent number: 6049799
    Abstract: The present invention provides a method and apparatus for managing links between documents and other data structures, such as applications. Search mechanisms may include a directory services search engine for locating objects. A directory object data structure search engine may evaluate, search, or the like, various objects to obtain important information contained in attributes or data members thereof. An association list handler may be a search engine for searching association lists stored as attributes of objects for identifying desired documents. A standard query data structure may be applied by a query resolver to a document location table identified by a document location object. A query generator may be responsible to formulate the standard query data structure, or for formulating queries for all three types of search engines. A directory services database may be searched for an object. An object may be searched for a particular data member or attribute.
    Type: Grant
    Filed: May 12, 1997
    Date of Patent: April 11, 2000
    Assignee: Novell, Inc.
    Inventors: Satwinder S. Mangat, Wayne Taylor, Steven Mahlum
  • Patent number: 6049546
    Abstract: A method for utilizing buffered switches to perform multipoint-to-multipoint multicasting within a telecommunication network. A switching feature known as cut-through forwarding is implemented for output-buffered switches, shared-memory switches and input-buffered switches.
    Type: Grant
    Filed: October 15, 1996
    Date of Patent: April 11, 2000
    Assignee: AT&T Corporation
    Inventor: Kadangode K. Ramakrishnan
  • Patent number: 6047329
    Abstract: A non-broadcast multi-access network system comprises a plurality of network servers at least a specific one of which servers employs Next Hop Resolution Protocol for converting a network layer address into a corresponding data link layer address. The specific network server comprises a routing table access section (102) for accessing a routing table to refer to the routing table representative of a routing of a network layer. An NHRP server table (103) stores server address information of at least a particular one of the network servers and network layer address information of the network layer managed by the particular network server as an address set. An NHRP server processing section (101) is supplied with a Next Hop Resolution Protocol packet having a destination network layer address for accessing the NHRP server table to judge whether or not the destination network layer address exists in the address set.
    Type: Grant
    Filed: August 14, 1997
    Date of Patent: April 4, 2000
    Assignee: NEC Corporation
    Inventors: Koichi Horikawa, Atsushi Iwata
  • Patent number: 6034951
    Abstract: The invention relates to a local area network operating in the asynchronous transfer mode comprising a plurality of terminals (1 to 4) which are formed each by a station (5), a radio device (7) for transmitting data between the terminals (1 to 4) and a network interface (6) including a controller (8) at least provided for setting up a connection, and comprising a switch unit (9) for switching cells between radio device (7), station (5) and controller (8). To effect a fast data transmission, the terminals (1 to 4) are provided each for a direct data exchange with another terminal (1 to 4). One terminal (1 to 4) then executes management functions in the network and exchanges data by means of at least one virtual link between a local user and a user of another terminal (1 to 4).
    Type: Grant
    Filed: September 3, 1997
    Date of Patent: March 7, 2000
    Assignee: U.S. Philips Corporation
    Inventor: Yonggang Du
  • Patent number: 6031834
    Abstract: According to the present invention, it is possible to provide a signal switching apparatus for reducing cross point identification name data stored in a memory required to generate switching control data according to a combination of a selected destination operating switch and a selected source operating switch so that a memory capacity of the memory can be reduced.
    Type: Grant
    Filed: April 10, 1997
    Date of Patent: February 29, 2000
    Assignee: Sony Corporation
    Inventors: Michio Mita, Kimiyasu Satoh
  • Patent number: 6012121
    Abstract: An apparatus for a distributed system having a plurality of nodes and a switch network for passing messages between nodes, each message being sent from a source node to a target node. Each node is connected to the switch network by an adapter having a count register for adding the value of the packets in messages received by the adapter to the value in the count register and a threshold register for containing a desired threshold value. An interrupt generator generates interrupts when the value in the count register is equal to or greater than the value in the threshold register. The value in the threshold register may be changed under program control to enable or disable interrupts.
    Type: Grant
    Filed: April 8, 1997
    Date of Patent: January 4, 2000
    Assignee: International Business Machines Corporation
    Inventors: Rama K. Govindaraju, Mandayam T. Raghunath
  • Patent number: 6011791
    Abstract: In a multi-processor system interconnecting processor units, memory units, and input/output units connected to input/output devices via a crossbar switch having a plurality of ports, the transmitter of each processor unit has a circuit for determining a destination of an access request in the following manner. For an access request to a main memory, the access request is transferred to all processor units and one memory unit storing the data to be accessed. For an access request to a memory mapped register of the input/output device, the access request is broadcast to all input/output units. For an access request to a memory mapped register belonging to any one of the processor units, memory units, and input/output units, the access request is broadcast to all units via the crossbar switch.
    Type: Grant
    Filed: November 12, 1996
    Date of Patent: January 4, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Tetsuhiko Okada, Naoki Hamanaka, Naohiko Irie, Takehisa Hayashi, Tetsuya Mochida, Masabumi Shibata, Youichi Tanaka, Yasuhiro Ishii
  • Patent number: 6005860
    Abstract: Routing information between an origination module and a destination module using a routing architecture. After an origination module (OM) receives information, a packet is transmitted to a routing architecture (RA) for routing to a destination module (DM) designated by the router packet. The RA interprets the router packet and adaptively routes the router packet to the DM so that the router packet is quickly processed by the DM. If the DM's queue is empty and the DM is not processing any other packets, the RA places the router packet in the queue and the DM reads its queue to process the router packet. If there is another router packet being processed by the DM, the RA adapts by placing the router packet in the queue. Once processing of the other router packet is complete, the DM processes the router packet in the queue. If there is already another router packet pending within the DM's queue, the RA adapts by creating another DM in memory to process the router packet.
    Type: Grant
    Filed: December 9, 1998
    Date of Patent: December 21, 1999
    Assignee: BellSouth Intellectual Property Corp.
    Inventors: Dewey Charles Anderson, Senis Busayapongchai, Audrey Dibrell, David J. Anderson
  • Patent number: 5999518
    Abstract: A distributed telecommunications switching subsystem (100) receives and distributes data packets passed between a plurality of switching subsystems or channel banks (102, 104, 106) and a data packet switch (110). Each channel bank (102) has a stored list of addresses. When a channel bank (102) receives a data packet, it compares the address of the data packet to its stored list of addresses, and transmits the data packet to another channel bank (104) if the address of the data packet does not correspond to any of the addresses in its stored list of addresses. The data packet is passed on until it reaches a channel bank (106) with a matching address or else it is appropriately handled by a last channel bank (106) in the chain. If the address of data packet matches an address in its stored list of addresses, the channel bank (102) passes the data packet through a subscriber interface card (120) to a customer premises equipment unit (108) corresponding to the address of the data packet.
    Type: Grant
    Filed: December 4, 1997
    Date of Patent: December 7, 1999
    Assignee: Alcatel USA Sourcing, L.P.
    Inventors: Dieter H. Nattkemper, Farzad S. Nabavi
  • Patent number: 5995510
    Abstract: A switching system for integratedly switching voice, data, image information and the like. The switching system comprises a plurality of front-end modules each adapted to perform a switching processing in association with a subscriber line or a trunk line, and a single or a plurality of central modules for interconnecting the plurality of front-end modules in star-type fashion and switching information prevailing between the front-end modules, in unit of block accommodating the information and a header added thereto to contain connection control information and in accordance with the contents of the header. The front-end modules are connected to the central module via inter-module highways each having frames occurring at a predetermined period and time slots contained in each frame to carry blocks.
    Type: Grant
    Filed: July 30, 1997
    Date of Patent: November 30, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Yoshito Sakurai, Shinobu Gohara, Kenichi Ohtsuki, Takao Kato, Hiroshi Kuwahara, Eiichi Amada
  • Patent number: 5982751
    Abstract: An improved rare probability connection call registration method using a PTI field information for an asynchronous transfer mode switching system which is capable of registering a rare probability connection code (RPCC) by using PTI field information, which includes the steps of setting a predetermined threshold value, checking payload type indication field information within each cell header which is currently being serviced, and determining whether the cell experienced congestion, continuously checking other cells when the cell did not experience congestion, increasing the congestion experienced counter value with respect to the service when the cell experienced congestion, and comparing the congestion experienced counter value with a predetermined threshold value within a previously designated unit time, clearing the congestion experienced counter value when the congestion experienced counter value is less than a predetermined threshold value within the previously designated unit time, increasing the conge
    Type: Grant
    Filed: December 10, 1996
    Date of Patent: November 9, 1999
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Chul Soo Kim, Sun Mi Kim, Kyung Chul Shin
  • Patent number: 5978376
    Abstract: A plurality of end devices are coupled via a shared port to an asynchronous network in which traffic is carried in cells. A cell multiplexer is disposed between the devices and the port and is adapted to multiplex cells from the devices to the port in the order in which they are received by the multiplexer. The multiplexer broadcasts cells received from the network to all of the devices. Each said device is allocated a respective VCI so that it can identify its own cells from the broadcast cells.
    Type: Grant
    Filed: January 23, 1997
    Date of Patent: November 2, 1999
    Assignee: Nortel Networks Corporation
    Inventors: Dhananjay Damodar Godse, William Anthony Gage, Michael A. Gazier, Alan Stanley John Chapman
  • Patent number: 5974048
    Abstract: An arrangement for connecting a device or end system to an ATM network incorporates a device controller coupled to the end system via first and second virtual channels across the network. The device controller discovers and boots the end system via the first virtual channel and performs proxy signalling means via the second virtual channel for on behalf of the end system.
    Type: Grant
    Filed: January 23, 1997
    Date of Patent: October 26, 1999
    Assignee: Nortel Networks Corporation
    Inventors: Dhananjay Damodar Godse, William Anthony Gage
  • Patent number: 5974452
    Abstract: Method for the determination of a destination ATM address as reply to an address resolution inquiry output by a source LAN emulation client of a first ELAN when the destination MAC address to be resolved is allocated to at least one LAN emulation client of a second ELAN and the first as well as the second ELAN are connected to a higher-ranking network, having the following method steps: encapsulation of the address resolution request present in the first ELAN as ELAN frame in a frame format of the CLS wide-area network and transmission via the CLS wide-area network to the second ELAN; de-encapsulation of the encapsulated address resolution request and handover to an LAN emulation server LES of the second ELAN in the ELAN frame format; resolution of the destination MAC address into an appertaining ATM address by this LAN emulation server of the second ELAN and output of an address resolution response; encapsulation of this address resolution response into the frame format of the CLS wide-area network and trans
    Type: Grant
    Filed: December 22, 1997
    Date of Patent: October 26, 1999
    Assignee: Aktiengesellschaft
    Inventors: Stefan Karapetkov, Ingrid Fromm, Bernhard Petri
  • Patent number: 5959992
    Abstract: A process for operating a communication equipment having a set of mechanically connected apparatuses being vertically and horizontally packed. Each apparatus comprises telecommunication functions such as echo cancellation, data compression or ISDN gateway, as well as vertical and horizontal mechanical and communication connections respectively allowing the vertical and horizontal exchanges of frames with neighboring apparatuses. The communication is based on a frame comprising n bytes routing header with n being an integer and an Asynchronous Transfer Mode (ATM) cell.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: September 28, 1999
    Assignee: International Business Machines Corporation
    Inventors: Alain Benayoun, Jean-Francois Le Pennec, Patrick Michel, Jacques Fieschi
  • Patent number: 5960074
    Abstract: A telecomputer network is described. The network comprises a redundant digital microwave communication system, at least one mobile vehicle, and a wireless local area network (LAN). In one embodiment, the microwave communication system transfers information using ethernet packet switching. In one embodiment, the wireless LAN transfers information using the TCP/IP protocol. The mobile vehicle is configured to transfer information as a single nomadic transmission/reception point between the microwave communication system and the wireless LAN.
    Type: Grant
    Filed: September 23, 1996
    Date of Patent: September 28, 1999
    Assignee: Curtis Clark
    Inventor: Curtis Clark
  • Patent number: 5959997
    Abstract: A hybrid access system and method using a hybrid access system point of presence router and a remote link adapter to connect a user computer terminal to a network for fast downstream information transfer by high speed information broadcasting with lower speed upstream information transfer through an independent upstream channel to the hybrid access system point of presence router. High speed downstream information transfer passes through a cable TV headend or a TV transmitter or a cell station.
    Type: Grant
    Filed: August 21, 1996
    Date of Patent: September 28, 1999
    Assignee: Hybrid Networks, Inc.
    Inventors: Eduardo J. Moura, Jan Maksymilian Gronski, Robert L. Packer, Robert A. Luxenberg, Frederick Enns
  • Patent number: 5956339
    Abstract: An apparatus for selecting a route in a packet-switched network where a plurality of candidate routes are available between a sending node and a receiving node. Total capacity calculation unit disposed in the sending node calculates the total channel capacity of each candidate route by summing up channel capacities of the inter-node links between the sending node and the receiving node. First selection unit chooses the candidate route(s) that exhibit the largest value of the total channel capacity. Uniformity calculation unit is activated when the first selection unit selected a plurality of candidate routes. The uniformity calculation unit calculates uniformity of each candidate route by evaluating the channel capacities of the inter-node links. The second selection unit chooses one of the candidate routes based on the calculated uniformity. This route will be used in packet transmission from the sending node to the receiving node.
    Type: Grant
    Filed: April 10, 1997
    Date of Patent: September 21, 1999
    Assignee: Fujitsu Limited
    Inventors: Takayuki Harada, Shinichi Araya
  • Patent number: 5953318
    Abstract: A distributed telecommunications switching system (100) is disclosed. The system includes a controller (118) in a first switching system (102). The control signal is transmitted to one or more intermediate switching system (104) and a terminating switching system (106) that generates and transmits a control signal which carries a plurality of credit allowance values. The intermediate switching system (104) receives the control signal and transmits data packets to the first switching system (102) in response to a first credit allowance value. The terminating switching system (106) receives the control signal and transmits data packets to the first switching system (102) in response to a second credit allowance value. The first switching system (102) transmits data packets from the intermediate switching system (104) and the terminating switching system (106) along with its own data packets according to its credit value to a data packet switch (110).
    Type: Grant
    Filed: December 4, 1997
    Date of Patent: September 14, 1999
    Assignee: Alcatel USA Sourcing, L.P.
    Inventors: Dieter H. Nattkemper, Farzad S. Nabavi
  • Patent number: 5949783
    Abstract: An apparatus and method are disclosed for efficiently supporting multiple VLAN's over an emulated LAN having a plurality of distributed LAN emulation servers. Each distributed LAN emulation server in an emulated LAN has a list of VLAN's that are reachable over each of its preestablished output connections. Each distributed LAN emulation server in the emulated LAN also has a predetermined threshold value for determining the most efficient utilization of its preestablished output connections.
    Type: Grant
    Filed: September 8, 1997
    Date of Patent: September 7, 1999
    Assignee: 3COM Corporation
    Inventors: David J. Husak, Floyd J. Backes
  • Patent number: 5940370
    Abstract: Connection control apparatus is provided for use in an ATM network to control ABR connections provided by the network, each such ABR connection having an agreed minimum transmission rate which it is permitted to exceed when there is spare capacity in the network. The apparatus includes: congestion detection circuitry (32, 33) for determining the end-to-end delay experienced by ATM cells of each ABR connection as they pass through the network; and a rate control circuit (30) connected to the said congestion detection circuitry for detecting, based on the determined end-to-end delay, when one of the ABR channels is congested. When congestion in one of the ABR channels is detected the rate control circuit imposes on the ABR connection concerned a maximum transmission rate that is higher than and dependent upon the said agreed minimum transmission rate for the connection concerned.
    Type: Grant
    Filed: June 5, 1996
    Date of Patent: August 17, 1999
    Assignee: Fujitsu Limited
    Inventors: Marc Simon Curtis, Ana Ferrandiz Roca
  • Patent number: 5940368
    Abstract: In a cell rate supervising system for supervising a rate of cells flowing in a certain direction, a binary mode congestion feedback loop terminating unit terminates a first congestion feedback loop on a downstream side of that direction. The first congestion feedback loop receives a first congestion management cell from the downstream side and turns it in a binary mode to the downstream side. Also, an explicit rate (ER) mode congestion feedback loop terminating unit is provided on an upstream side of the binary mode congestion feedback loop terminating unit, and terminates a second congestion loop on an upstream side of the direction. The second congestion feedback loop receives a second congestion management cell from the upstream side and turns it in an ER mode to the upstream side.
    Type: Grant
    Filed: March 10, 1997
    Date of Patent: August 17, 1999
    Assignee: NEC Corporation
    Inventors: Toru Takamichi, Satoshi Kamiya, Tutomu Murase
  • Patent number: 5926461
    Abstract: In a process for measuring switching delays in telecommunication networks having an asynchronous transfer mode, where cells containing information experience switching delays at switching exchanges, selected cells are provided with a counter, are switched in the same manner as other cells in switching exchanges, and are transmitted via the telecommunication network. The counter contained within the cell in the switching exchanges is increased in each case by a value corresponding to the switching delay, and the counter is read out after the transmission.
    Type: Grant
    Filed: April 22, 1997
    Date of Patent: July 20, 1999
    Assignee: Deutsche Telekom AG
    Inventors: Reinhard Habermann, Heinrich Doerken
  • Patent number: 5903612
    Abstract: A method to realize synchronization in a receiver (RX), of data (DAT) sent from a transmitter (TX) to the receiver (RX), with a signal (SIG) available in the receiver (RX). The method includes the following steps:in the receiver (RX) generating trigger signals (T) from the signal (SIG) available in the receiversending the trigger signals (T) from the receiver (RX) to the transmitter (TX); andupon receipt of the trigger signals (T) by the transmitter (TX) sending the data (DAT) from the transmitter (TX) to the receiver (RX).
    Type: Grant
    Filed: November 6, 1997
    Date of Patent: May 11, 1999
    Assignee: Alcatel Alsthom Compagnie Generale d'Electricite
    Inventors: Frank Octaaf Van Der Putten, Paul Marie Pierre Spruyt, Karel Adriaensen
  • Patent number: 5894481
    Abstract: The present invention is a fiber channel switch employing a distributed queuing algorithm for interconnecting a plurality of devices (workstations, supercomputer, peripherals) through their associated node ports (N.sub.-- ports) and employs a fabric having a shared memory coupled to a plurality of fabric ports (F.sub.-- ports) through a bi-directional bus over which memory addresses, frame data and communications commands are transmitted. Each F.sub.-- port includes a port controller employing a distributed queuing algorithm associated with a control network for communicating commands between the ports related to when and where frame transfers should be made, wherein the bi-directional bus provides an independent data network for access to the shared memory such that frames can be transferred to and from the shared memory in response to port controller commands.
    Type: Grant
    Filed: September 11, 1996
    Date of Patent: April 13, 1999
    Assignee: McData Corporation
    Inventor: David Book
  • Patent number: 5864556
    Abstract: A multiplexer for use in conjunction with a cell-based network, which includes a plurality of access terminals each of which receives respective cells, each of the cells having one of a plurality of different classifications, a plurality of FIFO buffers each of which is coupled to a respective one of the access terminals for queuing the cells received at the respective access terminals, a plurality of decoding elements each of which is coupled to a respective one of the FIFO buffers, and, an allocation circuit which generates a coded selection signal that is applied to each of the decoding elements, wherein the decoding elements each decode the coded selection signal for selectively reading the cells out of the FIFO buffers in a manner whereby the cells are read out of the FIFO buffers in an order which is dependent upon their classification.
    Type: Grant
    Filed: October 25, 1996
    Date of Patent: January 26, 1999
    Assignee: U.S. Philips Corporation
    Inventors: Georges Tibi, Jean-Pierre Gauthier
  • Patent number: 5862127
    Abstract: The present invention relates to a method for controlling the peak cell rate spacing of multiplexed ATM traffic.
    Type: Grant
    Filed: December 12, 1996
    Date of Patent: January 19, 1999
    Assignees: Electronics and Telecommunications Research Institute, Korea Telecommunications Authority
    Inventors: Dong Yong Kwak, Hong Shik Park
  • Patent number: 5859850
    Abstract: A method and apparatus for interfacing ATM network packet type communications to STM frame type communications. This method and apparatus is especially useful for interfacing isochronous ATM cells to STM frames. The apparatus concerns an elastic store which receives ATM cells and sorts them in a set of FIFOs into their respective frames. The FIFO storing and retrieval method removes jitter and delay. A controlled clock within the elastic store clocks reads the information out of the FIFOs and into a STM network.
    Type: Grant
    Filed: December 28, 1995
    Date of Patent: January 12, 1999
    Assignee: Lucent Technologies Inc.
    Inventor: Robert Leroy Lien
  • Patent number: 5860136
    Abstract: To provide fast access times with very large key fields, an associative memory utilizes a location addressable memory and lookup table to generate from a key the address in memory storing an associated record. The lookup tables, stored in memory, are constructed with the aid of arithmetic data compression methods to create a near perfect hashing of the keys. For encoding into the lookup table, keys are divided into a string of symbols. Each valid and invalid symbol is assigned an index value, such that the sum of valid index values for symbols of a particular key is a unique value that is used as an address to the memory storing the record associated with that key, and the sum of keys containing invalid index values point to a location in memory containing similar data. Utilizing the lookup tables set and relational operations maybe carried out that provide a user with a maximum number of key records resulting from a sequence of intersection, union and mask operations.
    Type: Grant
    Filed: December 28, 1993
    Date of Patent: January 12, 1999
    Inventor: Peter R. Fenner
  • Patent number: 5844904
    Abstract: A digital message switching system includes at least one digital message switching unit and a plurality of subordinate units each being coupled to the respective switching unit through a respective transmission link. In order to signal a request of a subordinate unit to transmit, that unit first sends at least one message of meaningless content to a higher-ranking unit and only then sends messages of meaningful content.
    Type: Grant
    Filed: August 22, 1996
    Date of Patent: December 1, 1998
    Assignee: Siemens Aktiengesellschaft
    Inventors: Yousif Ammar, Gerald Hoefer, Michael Alger-Meunier
  • Patent number: 5842224
    Abstract: To provide for fast access times with very large key fields, an associative memory utilizes a location addressable memory and look up tables to generate from a key an address in memory storing an associated record. The look up tables, stored in a memory, are constructed with the aid of arithmetic data compression methods to create a near perfect hashing of the keys. For encoding into the look up table, keys are divided into a string of symbols. Each symbol is assigned an index value, such that a modulo sum of index values for symbols of a particular key is a unique value that is used as an address to the memory storing the record associated with that key.
    Type: Grant
    Filed: June 30, 1994
    Date of Patent: November 24, 1998
    Inventor: Peter R. Fenner
  • Patent number: 5835484
    Abstract: A scheme for controlling a congestion in the communication network, capable of realizing a recovery from the congestion state by the operation at the lower layer level for the communication data transfer alone, without relying on the upper layer protocol to be defined at the terminals. In a communication network including first and second node systems, a flow of communication data transmitted from the first node system to the second node system is monitored and regulated by using a monitoring parameter. On the other hand, an occurrence of congestion in the second node system is detected according to communication data transmitted from the second node system, and the monitoring parameter used in monitoring and regulating the flow of communication data is changed according to a detection of the occurrence of congestion in the second node system.
    Type: Grant
    Filed: September 12, 1997
    Date of Patent: November 10, 1998
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsumi Yamato, Hiroshi Esaki
  • Patent number: 5831982
    Abstract: For the connection setup between output switching nodes and a target switching node of an ATM communication network consisting of subnetworks, a best route, as well as the relevant routing information, is determined such that alternate routes are also taken into account. The alternate routes are thereby loops via one or several further subnetworks to a not-yet-passed reentry node of the already-passed subnetwork. The method is particularly suited for ATM communication networks whose signaling takes place according to the PNNI protocol.
    Type: Grant
    Filed: December 17, 1996
    Date of Patent: November 3, 1998
    Assignee: Siemens Aktiengesellschaft
    Inventor: Heinrich Hummel
  • Patent number: 5828844
    Abstract: A telecommunications network is provided for establishing communication between at least one originating station and at least one destination station. The network includes a plurality of IP switches for addressing and routing data in accordance with an Internet protocol and an ATM protocol. A server, which is coupled to at least one of the IP switches, receives at least one service attribute requested by the originating station in communication with the IP switch. A network control point (NCP) is employed to provide data, in response to a request from the server, pertaining to the service attribute. At least one address database is associated with each of the IP switches. The address database includes a subset of the data available in the NCP.
    Type: Grant
    Filed: October 8, 1996
    Date of Patent: October 27, 1998
    Assignee: AT&T Corp.
    Inventors: Seyhan Civanlar, Vikram R. Saksena
  • Patent number: 5825772
    Abstract: Method and apparatus providing connection-oriented services for packet switched data communications networks. Directory services include distributed discovery of MAC addresses and protocol alias addresses. Topology services include a link state topology exchange among switches, which provides each switch with a complete topology graph of the network. This enables an access switch receiving a data packet to determine a complete path from a source end system to a destination end system. Another service includes resolution of broadcast frames to unicast frames, in order to reduce the amount of broadcast traffic. Policy restrictions may be applied prior to connection setup. Path determination services enable multiple paths from a source to a destination. Connection management includes source routed mapping of connections on the desired path.
    Type: Grant
    Filed: April 2, 1996
    Date of Patent: October 20, 1998
    Assignee: Cabletron Systems, Inc.
    Inventors: Kurt Dobbins, Thomas A. Grant, David J. Ruffen, Laura Kane, Theodore Len, Philip Andlauer, David H. Bahi, Kevin Yohe, Brendan Fee, Chris Oliver, David L. Cullerot, Michael Skubisz
  • Patent number: 5822320
    Abstract: An ATM terminal transmits an NHRP packet to an NHS based on an ANYCAST address thereof. A NHRP configuration server may be placed in the ATM network to hold NHS information in order to store the configuration, acquire an IP address and an ATM address of the NHS, and transmit the NHRP packet based on the acquired address. Each NHS is allowed to register its own information in the NHRP configuration server at a regular interval or when the information has been updated. When the NHS receives an NHRP register packet from an ATM terminal that is not managed thereby, the NHRP register packet is transferred to another NHS that manages the ATM terminal. The NHS may also execute authentication operation with respect to the NHRP register packet transferred from the ATM terminal that is managed thereby.
    Type: Grant
    Filed: November 18, 1996
    Date of Patent: October 13, 1998
    Assignee: NEC Corporation
    Inventors: Koichi Horikawa, Atsushi Iwata
  • Patent number: 5818853
    Abstract: An ATM switch including ECC encoder circuits each for generating, for an ATM cell as an information symbol, an ECC check symbol and for adding the ECC check symbol thereto, cell partitioning circuits each for subdividing an information field of an ATM cell into N partial cells, for subdividing a check symbol field into M partial cells, and for assigning an identical routing tag to the obtained partial cells (N+M) partial cell switches for respectively routing the (N+M) partial cells in an independent fashion based on the routing tag, and ECC decoder circuits for receiving the (N+M) partial cells thus routed and for achieving an error correction on the received partial cells.
    Type: Grant
    Filed: February 29, 1996
    Date of Patent: October 6, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Nakano, Takahiko Kozaki, Shinobu Gohara, Yoshihiro Ashi