Path Selection Or Routing Patents (Class 379/272)
  • Patent number: 7031450
    Abstract: A method and system is provided wherein routing information is obtained from previously cached information or from a gatekeeper. An originating gateway in a network receives a request for a connection and determines whether pertinent routing information is cached. If available, the cached routing is used to attempt to establish a connection. If no previously established routing is available, the originating gateway requests preferred routing from a gatekeeper, including prioritized selections of terminating gateways through which to make a connection to a designated call recipient.
    Type: Grant
    Filed: August 27, 2002
    Date of Patent: April 18, 2006
    Assignee: ITXL IP Holdings, S.A.R.L.
    Inventor: Tom Evslin
  • Patent number: 6980638
    Abstract: A failsafe configuration for alternative network telephony is disclosed. An indication as to whether an alternative network telephony call processing system is available to process calls from an associated piece of telephone equipment is received automatically and transparently to a user of the telephone equipment. Calls placed from the telephone equipment at a time when the alternative network telephony call processing system is available to process calls are processed via alternative network telephony. Calls placed from the telephone equipment at a time when the alternative network telephony call processing system is not available to process calls are processed via the public switched telephone network (PSTN).
    Type: Grant
    Filed: March 13, 2003
    Date of Patent: December 27, 2005
    Assignees: Vulcan Research LLC, Digeo, Inc.
    Inventors: Geoff Smith, Michael Lee, Steve Young, Todd Krein
  • Patent number: 6975717
    Abstract: A system and method are disclosed for selective processing of calls using alternative network telephony. Called party data is received indicating a destination to which a calling party using a local telephone equipment desires to place a call. It is determined transparently to the calling party whether the called party data satisfies a first criteria for completing calls via alternative network telephony. The call is completed using alternative network telephony if it is determined that the called party data satisfies the first criteria. The call is completed via the public switched telephone network (PSTN) if it is determined that the called party data does not satisfy the first criteria.
    Type: Grant
    Filed: March 13, 2003
    Date of Patent: December 13, 2005
    Assignees: Vulcan Research LLC, Digeo, Inc.
    Inventors: Geoff Smith, Michael Lee, Steve Young, Todd Krein
  • Patent number: 6956858
    Abstract: A routing table circuit for a router has one or more input ports and output ports for message communication. In the routing table circuit, one or more routing table memories store a plurality of routing table arrays. The routing table arrays are arranged hierarchically in levels, and each routing table array is associated with a predetermined subset of prefixes. Each routing table array has entries. The entries include a block default route pointer field to store a block default route pointer, if any, and a routing field. The route engine may access any level of table array by using a next level route pointer stored in the routing field. Using the block default route and the routing field, the present invention further reduces the number of memory accesses and the update cost for route insertion and deletion by identifying and skipping elements that do not require route updating.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: October 18, 2005
    Assignee: Mayan Networks Corporation
    Inventors: Yoichi Hariguchi, Thomas A. Herbert, Ryan T. Herbst
  • Patent number: 6940851
    Abstract: A pipeline-based matching scheduling approach for input-buffered switches relaxes the timing constraint for arbitration with matching schemes, such as CRRD and CMSD. In the new approach, arbitration may operate in a pipelined manner. Each sub-scheduler is allowed to take more than one time slot for its matching. Every time slot, one of them provides a matching result(s). The sub-scheduler can use a matching scheme such as CRRD and CMSD.
    Type: Grant
    Filed: July 23, 2001
    Date of Patent: September 6, 2005
    Assignee: Polytechnic University
    Inventors: Eiji Oki, Hung-Hsiang Jonathan Chao, Roberto Rojas-Cessa
  • Patent number: 6892169
    Abstract: A software interface used in designing communications circuits receives input from a user (20). In response, the software interface initiates accessing of a route plan (16) comprising a first route point group (38) associated with a first circuit end point (34), a second route point group (38) associated with a second circuit end point (34), and one or more routes (32) connecting the first and second route point groups (38). Each route (32) is available for use in designing the circuit. The software interface also initiates selection of a route (32) according to the route plan (16) and initiates the automatic assignment of the selected route (32) to the circuit in designing the circuit. The software interface provides information to the user (20) reflecting assignment of the route (32) to the circuit. The route plan (16) may be selected from among multiple route plans (16) according to a service application (14) automatically derived from an associated circuit order.
    Type: Grant
    Filed: December 13, 2000
    Date of Patent: May 10, 2005
    Assignee: Metasolv Software, Inc.
    Inventors: David C. Campbell, Brenda D. Dunn, Mark W. McGuire, Joseph A. Peterson, John P. Reilly, Mary Kim Westervelt
  • Patent number: 6885663
    Abstract: A time/space switching component is provided with multiple functionality that includes a time switching unit, of a space switching unit of a data channel sequence correction unit and of a control unit. As a result of corresponding mode selection, the different functionalities for a switching network are obtained with a single component, resulting in a significant reduction in an overall expenditure for development and manufacture.
    Type: Grant
    Filed: December 18, 2000
    Date of Patent: April 26, 2005
    Assignee: Siemens Aktiengesellschaft
    Inventors: Karsten Laubner, Marcel-Abraham Troost
  • Patent number: 6816585
    Abstract: A method for routing of incoming prioritized telecommunication traffic in a telecommunication network by applying an algorithm of finding optimal path to an augmented graph built for said telecommunication network. The telecommunication network is represented as a network graph comprising nodes (A, B, C, D, E) and real links (AB, BC, CD, ED, AE) bridging the nodes, while the augmented graph is a graph built on the basis of the network graph by adding to it virtual links (ABC1, . . . , EDC3). The augmented graph comprises nodes and edges, wherein the edges of the augmented graph are weighed to reflect priority of the telecommunication traffic presently taking place there-through. For placing a new call according to the method, a pathfinder optimization algorithm is applied to the augmented graph to determine an optimal pathfinder solution, having the minimal total weight, for routing the new call in the augmented graph.
    Type: Grant
    Filed: July 16, 2001
    Date of Patent: November 9, 2004
    Assignee: ECI Telecom Ltd.
    Inventors: Marcelo Blatt, Noga Peled
  • Patent number: 6766015
    Abstract: A method of hunting for a communication channel in a communication system where a plurality of communication lines each have a plurality of communication channels includes the steps of maintaining a record of current channel statuses of the communication channels with respect to all the communication lines, and distributing busy channels evenly among the communication lines by selecting a communication channel based on the record of channel statuses and assigning the selected communication channel to a call.
    Type: Grant
    Filed: March 15, 2000
    Date of Patent: July 20, 2004
    Assignee: Fujitsu Limited
    Inventor: Hirokazu Iwakura
  • Patent number: 6748070
    Abstract: Network resources for a call between a calling party and a called party are allocated. The network resources for the call are reserved based on a reservation request. The network resources are reserved before any one network resource from the reserved network resources is committed. The reserved network resources for the call are committed when a called party indicates acceptance for the call.
    Type: Grant
    Filed: June 24, 2002
    Date of Patent: June 8, 2004
    Assignee: AT&T Corp.
    Inventors: Charles Robert Kalmanek, Jr., William Todd Marshall, Partho Pratim Mishra, Douglas M Nortz, Kadangode K Ramakrishnan
  • Patent number: 6614904
    Abstract: An apparatus is disclosed for effecting a communication arrangement of a plurality of communication circuits between first connection loci of a first switch array and second connection loci of a second switch array. The apparatus comprises: (a) a first connection interface with the first switch array having first interconnection loci; (b) a second connection interface with the second switch array having second interconnection loci; (c) a plurality of communication paths at least equal in number to the plurality of communication circuits intermediate the first and second connection interfaces; (d) a first router connected with the first switch array and connection interface; and (e) a second router connected with the second switch array and connection interface. The first and second router interfaces cooperate to effect a plurality of routing connections among the first connection loci, the second connection loci and selected communication paths to establish the communication arrangement.
    Type: Grant
    Filed: August 9, 2000
    Date of Patent: September 2, 2003
    Assignee: Alcatel
    Inventor: James Robert Fyne
  • Patent number: 6611591
    Abstract: A telephony system includes a switch coupled to a call agent and a legacy application, and further coupled to resources, some controlled by the call agent and others controlled by the legacy application. The switch processes connection requests from the call agent and the legacy application, and, using a resource emulator as an intermediary, establishes connections between call agent controlled resources and legacy application controlled resources.
    Type: Grant
    Filed: January 6, 2000
    Date of Patent: August 26, 2003
    Assignee: Cisco Technology, Inc.
    Inventors: Bradley J. McNiff, Cedric H. Druce
  • Patent number: 6567516
    Abstract: A method of controlling affiliation of a remote line-collection device with a plurality of switches connected via a network includes the steps of providing each switch with a backup-storage area in advance in addition to a normal storage area, and transferring control data of the remote line-collection device from the normal storage area of a first switch to the backup-storage area of a second switch when affiliation of the remote line-collection device is changed from the first switch to the second switch.
    Type: Grant
    Filed: July 1, 1999
    Date of Patent: May 20, 2003
    Assignee: Fujitsu Limited
    Inventors: Hirofumi Mitome, Akihiro Horiuchi, Hiromitsu Kajiyama, Shunichi Shibata, Kenji Maeda
  • Patent number: 6507648
    Abstract: The invention is a novel method of processing incoming and outgoing call requests by a switching unit such as a KSU, PBX or PC server. Each established circuit and each call request is associated with a priority. For an outgoing call request, if an available external bandwidth channel of the appropriate type is found, then a circuit is established at once. However, if there is no available external bandwidth channel of the appropriate type, then the priority of the outgoing call request is checked against the priority of the established circuits. If a lower-priority circuit is found, then that circuit is torn down and a new circuit is established between the internal bandwidth channel carrying the outgoing call request and the external bandwidth channel formerly occupying the established circuit that was torn down. In the case of an incoming call request, a destination terminal device and associated internal bandwidth channels will be specified and availability thereof is verified.
    Type: Grant
    Filed: December 23, 1998
    Date of Patent: January 14, 2003
    Assignee: Nortel Networks Limited
    Inventors: Kevin W. Golka, John R. Donak, Lorne A. Porter
  • Patent number: 6411703
    Abstract: Method and system are provided for efficient telephone number portability within a geographically dispersed telephony and the like switching system, wherein ported telephone numbers, when dialled and found non-existent at their number-inherent destination, a “Release Treatment” with a trigger (automatic flexible routing) searches in a database from the originating switching node or office, whereupon their new network node address is directly connected to following normal routing procedures; thus permitting realistically affordable telephone number portability, particularly local number portability (LNP).
    Type: Grant
    Filed: February 9, 1998
    Date of Patent: June 25, 2002
    Assignee: Nortel Networks Limited
    Inventors: Edgar Martinez, Locillo Giuseppe Pino, Charles Richard Wiebe
  • Publication number: 20020018550
    Abstract: A method for destination control in an intelligent network, where a destination list for a subscriber's telephone number is provided which has entries associating particular connections with the subscriber during predetermined time periods, as a result of which incoming calls for the subscriber's telephone number are transferred to an appropriate connection indicated as destination in the entry. When the subscriber logs on and/or off at a terminal using an access point to the intelligent network, an event message is transmitted which changes the destination list, the event message being evaluated by taking into account conditions, and a corresponding entry in the destination list being ascertained and/or changed on such basis.
    Type: Application
    Filed: May 29, 2001
    Publication date: February 14, 2002
    Inventor: Tania Abdel Hafez
  • Publication number: 20010046865
    Abstract: In order to increase the channel capacity of a wireless local loop network, advantage is taken of the fixed location of each subscriber radio, and the ability to independently configure each subscriber's antenna, to provide antenna cross polarization isolation into the cellular layout of the WLL network, and thereby provide an additional layer of interference rejection. Such a cross polarization assignment scheme, in combination with frequency reuse allocation, provides a substantial increase in the C/I ratio and thereby allows an expansion of the reuse of frequency channels.
    Type: Application
    Filed: August 6, 1998
    Publication date: November 29, 2001
    Inventors: ROBERT C. HILDEBRAND, JAMES H. CHINNICK
  • Patent number: 6282278
    Abstract: A method and apparatus for automatically establishing an audio conference call where one of a number of audio conference call service providers must be selected. With this invention a resource broker receives requests from a number of users desiring to establish an audio conference call. Profile data on a number of conference call service providers is maintained by the resource broker. Based on the profile data and the requests from the users, one of the audio conference call service providers is selected, and the selected audio conference service provider then establishes an audio conference call in accordance with the request from the users.
    Type: Grant
    Filed: April 22, 1998
    Date of Patent: August 28, 2001
    Assignee: International Business Machines Corporation
    Inventors: Yurdaer Nezihi Doganata, Asser Nasreldin Tantawi
  • Patent number: 6225888
    Abstract: In known telecommunications systems using multiple access the terminal equipment assumes that the network element is genuine while the network element assumes that the terminal equipment is genuine. This allows false terminal equipment, a false network element or a third party to penetrate the system. The proposed commitment protocol applies bit block commitment known from cryptography and a shared encryption key and the authentication is divided into two parts, whereby one part of it is done by the terminal equipment and the other part is done by the network. The terminal equipment (MS) sends to the network element (BTS) a pseudo identifier (AMSI) which it has formed, whereupon encryption keys (MKEY, BKEY) are exchanged. Only when the network element has revealed its true identity, will the terminal equipment send the required information (IMSI, RND1, RND2) encrypted with a combination of the keys.
    Type: Grant
    Filed: June 8, 1999
    Date of Patent: May 1, 2001
    Assignee: Nokia Telecommunications Oy
    Inventor: Jari Juopperi
  • Patent number: 6205557
    Abstract: A telecommunications network includes at least an active and a standby call server, the standby call server becoming active upon failure of the active call server. To facilitate rapid switch-over from the active to the standby call server and to prevent the loss of call processing data for calls in the call setup stage, the active call server sends call information to the standby call server during intervals in which the active call server is awaiting subsequent signaling messages from elements of the telecommunications network. In this way, the standby call server has the call information needed to commence call processing upon failure of the active call server, and the active call server makes efficient use of time while awaiting a reply signaling message.
    Type: Grant
    Filed: June 9, 1998
    Date of Patent: March 20, 2001
    Assignee: AT&T Corp.
    Inventors: Koan S. Chong, Martin C. Dolly, Andrew R. Jacob, Carolyn R. Johnson, Wonseok Lee, David George Lewis, Pamela M. Moricz, Mark A. Ratcliffe
  • Patent number: 6137876
    Abstract: A Network Call Trace (NCT) method and system enables a call path route to be traced in a telecommunications network. A Type of Digit (TOD) in the Generic Digits Parameter (GDP) for an Integrated Services Digital Network (ISDN) User Part (ISUP) command can be utilized to realize the NCT. A listing of Switch IDs (SIDs) from the originating subscriber's switch to the terminating subscriber's switch is provided so that routing inefficiencies can be discovered. In one embodiment, an Initial Address Message (IAM) is transmitted with a TOD Network Call Trace in the GDP. The NCT includes the SID of the originating switch. Any intermediate switches between the originating switch and the terminating switch likewise append their own SID onto the NCT list of SIDs. Finally, the terminating switch also adds its SID onto the end of the NCT list. This NCT list may then be transmitted and displayed for analysis.
    Type: Grant
    Filed: December 4, 1997
    Date of Patent: October 24, 2000
    Assignee: Ericsson Inc
    Inventors: Ping Wong, Lars A. Tovander
  • Patent number: 6128378
    Abstract: A system and method for processing electronic data and voice audio calls providing an interLATA (Local Access Transport Area) fast connect routing scheme that bypasses an interexchange carrier. An interLATA communication circuit is established between a first switch in a first LATA and a second switch in a second LATA. The step of routing a call from the first switch to the second switch is performed. The call is routed to an interexchange carrier if the interexchange carrier is not a subscriber to a fast connect service. The step of bypassing the interexchange carrier is performed if the interexchange carrier is a subscriber to the fast connect service. Upon determining that the interexchange carrier is a subscriber to the fast connect service, the call is directly routed from the first switch located in the first LATA to the second switch located in the second LATA without utilizing interexchange carrier trunks or switches.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: October 3, 2000
    Assignee: Lucent Technologies, Inc.
    Inventors: Jon R. Diener, Kathryn A. Laskowski
  • Patent number: 6044059
    Abstract: Contention losses are minimized in path searching, circuit-switched networks by adding intelligence to the last stage of the network. A count of number of bytes remaining to be transferred in each active message is maintained in real time for each output port of the network. If contention arises at the last stage switch being requested in camp-on mode to make a connection to a busy output port, the switch checks the bytes remaining count and responds differently depending on how the bytes remaining count compares to a preset threshold register. If the count remaining is below the threshold, the last stage switch accepts the camp-on request, because the desired output port will be available shortly. If the count remaining is above the threshold or below the threshold but another user is camped-on, the switch rejects the camp-on request to the last stage, because the desired output port will not be available shortly. In this case further path searching would be meaningless.
    Type: Grant
    Filed: June 26, 1997
    Date of Patent: March 28, 2000
    Assignee: International Business Machines Corporation
    Inventor: Howard Thomas Olnowich
  • Patent number: 6034956
    Abstract: The multi-stage interconnection network of the present invention includes the use of switches in the first stage that have parallel path seeking capabilities. With these switches, a directed flash-flood can be instigated from any one node wherein multiple paths through the network to a designated destination node are tried in parallel in an attempt to find a connection path therebetween. The switches in the first and second stages are interconnected such that each switch in the first stage is connected with every possible priority level to the switches of the second stage. The parallel path seeking switches and network are further configured to test for rejection of the flash-flood by monitoring all connections in combination.
    Type: Grant
    Filed: June 29, 1998
    Date of Patent: March 7, 2000
    Assignee: International Business Machines Corporation
    Inventors: Howard Thomas Olnowich, Jehoshua Bruck, Michael Hans Fisher, Joel Mark Gould, John David Jabusch, Arthur Robert Williams
  • Patent number: 5995618
    Abstract: A method of operating a switched communications network redirects certain types of messages away from the switch to free up switch resources for other messages, thereby decreasing the size of switch needed or delaying necessary switch size upgrading. Messages are redirected by intelligent concentrators that can connect certain types of messages to their destinations without routing them through the switch. For example, messages between an origination and a destination connected to the same concentrator need not be sent through the switch. Similarly, messages between originations and certain high-volume, long-duration destinations such as data service gateways can be connected directly without passing through the switch. The intelligent concentrators communicate with the switch on a control channel so that the switch remains aware of the status of each origination or destination (e.g., so that it knows not to attempt to route messages to an origination or destination that is in use).
    Type: Grant
    Filed: July 8, 1996
    Date of Patent: November 30, 1999
    Assignee: AT&T Corp
    Inventors: James Frederick Bradley, Bruce Gilbert Cortez, Cheryl F. Newman, John Paggi, David Schmuckler
  • Patent number: 5974132
    Abstract: The present invention is a novel architecture design for adjunct based architectures. The architecture is built on two key principles; routing traffic based on geographic origin and routing based on customer group. In order to implement the geographic routing, the communications network is split into regions. A method used to achieve optimal regions is described. Further realization of the geographic routing entails a design of the architecture regions, determining the number of adjuncts/region and equally distributing the loads across the adjunct sites. Also, described is the method for optimally homing traffic between the OAS and TAS A and between TAS A and TAS B. The architecture eliminates deficiencies in prior art architectures such as intertoll focusing, architecture instability and reliability.
    Type: Grant
    Filed: November 14, 1997
    Date of Patent: October 26, 1999
    Assignee: AT&T Corp.
    Inventors: Dominic Ricciardi, Jerry Allen Robinson
  • Patent number: 5892451
    Abstract: An enhanced desktop management interface within a computing device interfaces with a management information system. The enhanced desktop management interface includes a service layer which has a management interface and a component interface. A plurality of management applications interact with the management interface of the service layer. Also, a plurality of manageable elements interface with the component interface of the service layer. When a primary communication path interface is available, the enhanced desktop management interface communicates with the management information system through the primary communication path. When the primary communication path interface is not available and an alternate communication path interface is available, the enhanced desktop management interface communicates with the management information system through the alternate communication path.
    Type: Grant
    Filed: October 9, 1996
    Date of Patent: April 6, 1999
    Assignee: Hewlett-Packard Company
    Inventors: Gregory J. May, Colin I'Anson
  • Patent number: 5870460
    Abstract: A system allocates data links between a switch and a database for data transactions in a telecommunications network. The data links between the switch and the database carry the transaction data for providing routing, card verification, address translation information, etc. by the database. The Flexible Link Selection Algorithm provides for accessing the data links using the round-robin method, wherein each data link is accessed sequentially to transport the data to and from the database. Alternatively, the Flexible Link Selection Algorithm provides for accessing the data links using dynamic allocation based on the least cost routing between the switch and the database. In the latter mode, the switch uses the least "expensive" database, i.e., database having the least cost routing between the switch and the database, until the volume of data transactions in the data links associated with that database exceeds a predetermined threshold level.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: February 9, 1999
    Assignee: MCI Communications Corporation
    Inventor: Paul D. Litzenberger
  • Patent number: 5852407
    Abstract: A multistage interconnection network capable of performing highly reliable communications with less hardware. In the multistage interconnection network for interconnecting a plurality of nodes, the first and final stages each have switches two times as large as the number of switches at an intermediate stage. Two output ports of each node are connected to the input ports of different first stage switches, and two input ports are connected to the output ports of final stage different switches. The input ports of switches of the intermediate stage are connected to the output ports of first stage different switches, and the output ports are connected to the input ports of final stage different switches. At least one output port of each switch at the first stage is directly connected to at least one input port of an optional switch at the final stage.
    Type: Grant
    Filed: June 14, 1996
    Date of Patent: December 22, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Masato Ishii, Patrick Hamilton
  • Patent number: 5825301
    Abstract: In a cross connect apparatus, a switch section includes a plurality of switches and having n input terminals and m output terminals. A control section reads a current connection information indicative of a current connection state of the switch section in response to a connection command, and determines based on the read connection information, whether it is allowed to establish a connection state of the switch section designated by the connection command. When it is determined to be allowed, the control section establishes a new connection state of the switch section designated by the connection command.
    Type: Grant
    Filed: May 13, 1996
    Date of Patent: October 20, 1998
    Assignee: NEC Corporation
    Inventor: Yuuki Yoshifuji
  • Patent number: 5774067
    Abstract: A multi-stage interconnection network includes the use of switches in the first stage that have parallel path seeking capabilities. With these switches, a directed flash-flood can be instigated from any one node wherein multiple paths through the network to a designated destination node are tried in parallel in an attempt to find a connection path therebetween. The switches in the first and second stages are interconnected such that each switch in the first stage is connected with every possible priority level to the switches of the second stage. The parallel path seeking switches and network are further configured to test for rejection of the flash-flood by monitoring all connections in combination.
    Type: Grant
    Filed: October 16, 1997
    Date of Patent: June 30, 1998
    Assignee: International Business Machines Corporation
    Inventors: Howard Thomas Olnowich, Jehoshua Bruck, Michael Hans Fisher, Joel Mark Gould, John David Jabusch, Arthur Robert Williams
  • Patent number: 5761286
    Abstract: Communications across a network (16) between a calling multimedia terminal (10) and at least one called multimedia terminal (12) is readily facilitated by assigning each terminal an endpoint identifier that establishes its communications path requirements. Upon entry by a calling terminal of its end-point identifier and the end-point identifier of each called terminal, a service hub (20) associated with the network automatically configures the network to provide a communications path having the appropriate attributes to connect the terminals together.
    Type: Grant
    Filed: March 19, 1996
    Date of Patent: June 2, 1998
    Assignee: AT&T Corp
    Inventors: Shovon Das, James R. Feeney
  • Patent number: 5652834
    Abstract: A method of avoiding undesirable interferences between services in a telecommunications system that includes basic software for a basic service and supplemental software for services supplemental to the basic service. The supplemental software is divided into action software which acts solely on the basic service, and supplemental software which acts on the remaining supplemental software. A supplemental service is represented by action elements. Combinations of action elements form nodes in a mathematical binomial tree. Only those combinations which correspond to interference, i.e., an undesirable behaviour, between supplemental services will form a number of structures, called interference event trees. Before a supplemental service can be executed, its action elements are compared with nodes in the interference event trees (55), with the intention of ascertaining whether or not the former coincide with action elements belonging to the nodes in the latter.
    Type: Grant
    Filed: June 10, 1994
    Date of Patent: July 29, 1997
    Assignee: Telefonaktiebolaget LM Ericsson
    Inventor: Rickard Jansson
  • Patent number: 5640319
    Abstract: A system for employing a computer to control a device to provide a plurality of services for a plurality of entities. Each entity corresponds to exactly one of the services and each service has its own copy of the code which defines the service. The system associates a process which executes the service with each service. The code for a service defines a finite state machine which is continually executed by the service's process. While in a given state, the finite state machine may traverse a decision graph which is directly accessible to the process. Actions to be taken on traversal of a node of the decision graph may be defined in the finite state machine. The service's process communicates with other processes and with itself by means of interprocess messages. Each state of the finite state machine contains event handlers for responding to messages received by the service's process.
    Type: Grant
    Filed: March 18, 1991
    Date of Patent: June 17, 1997
    Assignee: Lucent Technologies Inc.
    Inventors: Brian George Beuning, Seymour Bloom, Raymond Eugene Bright, Jr., Steven Lloyd Greenspan, Joel M. Marks, Michael James Morgan, Timothy Jerome Scale, Bruce Fat Wong
  • Patent number: 5521591
    Abstract: A class of switching networks is comprised of expansive logical clusters and/or dispersive logical clusters. These clusters are of low degree. The class of networks include multibutterfly networks as well as multi-Benes networks. These networks provide for fault tolerance and routing and for efficient routing. Moreover, routing is provided in a non-blocking fashion.
    Type: Grant
    Filed: March 25, 1994
    Date of Patent: May 28, 1996
    Assignee: Massachusetts Institute of Technology
    Inventors: Sanjeev Arora, Thomas F. Knight, Jr., Frank T. Leighton, Bruce M. Maggs, Eliezer Upfal
  • Patent number: 5519694
    Abstract: A switching network incorporates expander graphs such as multibutterflies but avoids the wiring complications resulting from the randomness of such graphs. The network includes metanodes, each having plural routers. Channels of multiple interconnections are connected between the metanodes according to an upper level expander graph. Interconnections within the channels are randomly connected. Interconnections on the channels may be time multiplexed and they may be dynamically assigned to routers within a metanode.
    Type: Grant
    Filed: February 4, 1994
    Date of Patent: May 21, 1996
    Assignee: Massachusetts Institute of Technology
    Inventors: Eric A. Brewer, Frederic T. Chong
  • Patent number: 5454034
    Abstract: An end office of the PSTN, which employs independent switching networks which share one or more office codes, is served by a single assigned node on the CCS network. The signaling processor which serves the assigned node, screens all incoming call messages (IAM)'s; directs messages which include an appropriate Channel Identification Code (CIC) to the switching network that serves that CIC; rejects messages that include an improper CIC; and requests that the calling office assign a different CIC to the incoming call.
    Type: Grant
    Filed: November 23, 1993
    Date of Patent: September 26, 1995
    Assignee: AT&T Corp.
    Inventor: Ronald B. Martin
  • Patent number: 5442691
    Abstract: A method and apparatus for routing calls in a switched digital network and a processor for use in such a network are provided in which tables of call control information store information for different categories of call control information in separate parts of the table or in separate tables. The information in the tables is available for different network entities to share in routing calls. The separation of different categories of information simplifies the task of making changes to call control tables and can allow certain of the separate tables to be portable across the network.
    Type: Grant
    Filed: November 23, 1993
    Date of Patent: August 15, 1995
    Assignee: International Business Machines Corporation
    Inventors: Steven Price, Barry J. Worley
  • Patent number: 5408231
    Abstract: A method and system for finding a path through a communications matrix represents the assignment of a center stage switch through an input switch to input gates by an input stage array, center stage switch connections between an input stage switch and an output stage switch by a center stage array, and output stage switch connections to output gates by an output stage array, as well as representing idle input switch links to the center stage switches by an idle input array and idle output switch links from the center stage switches by an idle output array.
    Type: Grant
    Filed: July 29, 1994
    Date of Patent: April 18, 1995
    Assignee: Alcatel Network Systems, Inc.
    Inventor: Edward K. Bowdon
  • Patent number: 5386417
    Abstract: A communications switch communicates a message to a particular access network endpoint by forwarding an identification of that endpoint along with the message, link-by-link, through the access network, the forwarding being accomplished by using previously stored routing information identifying, at the switch and at each cross-connection point, a particular downstream link over which the endpoint can ultimately be reached. The links connecting the cross-connection points are multiplexed links supporting digital loop carrier and fiber-in-the-loop communications. The routing information is generated and stored automatically by having each network element report information about itself upstream into the network.
    Type: Grant
    Filed: August 27, 1993
    Date of Patent: January 31, 1995
    Assignee: AT&T Corp.
    Inventors: Thomas H. Daugherty, Dennis L. DeBruler, Daniel S. Greenberg, David J. Hodgdon, Douglas J. Murphy
  • Patent number: 5381405
    Abstract: A communications switch communicates a message to a particular access network endpoint by forwarding an identification of that endpoint along with the message, link-by-link, through the access network, the forwarding being accomplished by using previously stored routing information identifying, at the switch and at each cross-connection point, a particular downstream link over which the endpoint can ultimately be reached. The links connecting the cross-connection points am time-division-multiplexed links supporting digital loop carrier and fiber-in-the-loop communications. The routing information is generated and stored automatically by having each network element report information about itself upstream into the network.
    Type: Grant
    Filed: August 27, 1993
    Date of Patent: January 10, 1995
    Assignee: AT&T Corp.
    Inventors: Thomas H. Daugherty, Dennis L. DeBruler, Daniel S. Greenberg, David J. Hodgdon, Douglas J. Murphy
  • Patent number: 5371732
    Abstract: Known methods of detecting routing loops in telecommunication networks are cumbersome and time-consuming. In addition, the probability that an existing routing loop is even actually detected is too low. In a method of detecting a routing loop according to the invention, paths whose lengths are stored are assembled. As soon as the length of a (partly assembled) path exceeds a predetermined value which is greater than, or equal to, the largest existing path length in the telecommunication network, this indicates the existence of a routing loop.
    Type: Grant
    Filed: February 8, 1993
    Date of Patent: December 6, 1994
    Assignee: Koninklijke PTT Nederland N.V.
    Inventors: Franciscus W. A. Brocken, Cyrillus G. J. Houben
  • Patent number: 5325089
    Abstract: Two-stage, at least doubled ATM reversing switching network having (2n.times.2n) switching matrices. For expanding a two-stage, doubled ATM self-routing reversing switching network, the switching matrices of the B switching stage can be respectively doubled in one redundancy level after another without interrupting operation given a simultaneously, respective halving of the plurality and filling of duplex link groups formed from the very outset and proceeding between A-switching stage and B-switching stage, of which duplex link groups only duplex links of one and the same group of links are occupied for every connection lasting during an expansion of the switching network.
    Type: Grant
    Filed: March 2, 1992
    Date of Patent: June 28, 1994
    Assignee: Siemens Aktiengesellschaft
    Inventor: Ernst-Heinrich Goeldner
  • Patent number: 5313590
    Abstract: A network and method for interconnecting a plurality of router elements in a parallel computer. The network forms a routing system for routing data from source processing elements to destination processing elements. The input lines and output lines of each router chip are prioritized. Higher priority output lines from a given output group of a first routing element are connected to low priority input lines of a second routing element and lower priority output lines from the output group of the first rotating element are connected to higher priority input lines of the second routing element.
    Type: Grant
    Filed: January 5, 1990
    Date of Patent: May 17, 1994
    Assignee: MasPar Computer Corporation
    Inventor: Stuart A. Taylor
  • Patent number: 5260934
    Abstract: A growable interconnect fabric cell switch module including a plurality of first cell switches for interconnecting cells; a plurality of second cell switches for interconnecting the cells outputted from the first cell switches; a plurality of third cell switches for interconnecting the cells outputted from the second cell switches; and a path arbitrating device for making a decision on cell transfer permission and on which second cell switch ought to be used in a cell transfer, based on a demanded cell number, which indicates a number of the cells which demand to be transferred from each first cell switch to each third cell switch.
    Type: Grant
    Filed: August 16, 1991
    Date of Patent: November 9, 1993
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tsutomu Tanaka, Hiroshi Yokota
  • Patent number: 5258977
    Abstract: A switching network for an asynchronous time-division multiplex transmission system includes a first stage having a plurality of switching blocks (4 to 7), to which are applied over auxiliary lines cells and routing information intended for various trunk lines and which are coupled to at least one switching block (8, 9) of a second stage. Inputs of switching blocks (4 to 7) of the first stage are coupled to auxiliary lines and at least one output of a switching block (8, 9) of the second stage. Outputs of switching blocks of the first stage are coupled to trunk lines and to at least one input of a switching block of the second stage. A cell extraction circuit (56 to 61) which is always coupled to a control circuit (10 to 15) of the associated switching block is coupled either to at least one input or to at least one output of each switching block.
    Type: Grant
    Filed: August 29, 1991
    Date of Patent: November 2, 1993
    Assignee: U.S. Philips Corp.
    Inventors: Roland Wolker, Christine Mertelmeier
  • Patent number: 5175539
    Abstract: Interconnecting network for simultaneous selective connecting of each of N inputs to one of N outputs has an input section which includes the inputs and contains at least the consecutive stages 1 to n-1 of a n-stage baseline network and has N outputs, and an output section which has N inputs which are connected to the N outputs of the input section, includes a n-stage baseline network and has N outputs which form the outputs of the interconnecting network. The order of the n-1 stages following the inputs is the same in both baseline networks.
    Type: Grant
    Filed: November 21, 1990
    Date of Patent: December 29, 1992
    Assignee: Max-Planck-Gesellschaft zur Foerderung der Wissenschaften E.V.
    Inventor: Harald Richter
  • Patent number: 5040173
    Abstract: A network control arrangement where path hunts through a first network are performed with reference to a second network that is topologically equivalent to the first. Path hunts through a crossover network, well-suited for implementation in the photonics domain, are performed with reference to a topologically equivalent shuffle network using a very efficient, shuffle network path hunt algorithm.
    Type: Grant
    Filed: May 8, 1989
    Date of Patent: August 13, 1991
    Assignee: AT&T Bell Laboratories
    Inventor: Gaylord W. Richards
  • Patent number: 5021968
    Abstract: A method manages cable in a building structure that includes the capabilities of automatically routing the cable between two locations in the structure, displaying the cable route, providing alternate cable routes, reporting on the cable and components of the structure, and alerting the user when percent fill capacity of the cable run is exceeded. The method also maintains the service and status of any location in the cable run.
    Type: Grant
    Filed: November 20, 1989
    Date of Patent: June 4, 1991
    Assignee: Robertson-Ceco Corporation
    Inventor: John A. Ferketic
  • Patent number: 4993016
    Abstract: A network control arrangement where two or more path hunt operations are performed in parallel using one or both of two techniques: (1) reading a memory for a second path hunt operation during the time that information read from the memory for a first path hunt operation is being processed to select a path, and (2) maintaining duplicate memories and reading from them both to perform two path hunt operations before either memory is updated. A disjoint path check unit rapidly determines whether all of the network paths from a first inlet to a first outlet are disjoint from all of the network paths from a second inlet to a second outlet. Plural path hunts are performed only when all network paths from the first inlet to the first outlet are determined to be disjoint from all network paths from the second inlet to the second outlet.
    Type: Grant
    Filed: May 8, 1989
    Date of Patent: February 12, 1991
    Assignee: AT&T Bell Laboratories
    Inventor: Gaylord W. Richards