Abstract: An apparatus and methods are provided for the communication of a data stream and management of faults in a multipath data network having a protected ring-in-ring network architecture. The data stream is communicated over redundant paths between various nodes located throughout the network. Each node is capable of dropping and inserting data from the data stream before passing it on to the next node. A single transmitter in communication with an intelligent splitter at each node is utilized to simultaneously transmit the data stream over the redundant paths. In the event of a fault over one of the paths in the network, the intelligent splitter manages the operation of the single transmitter so that the data stream is communicated over an alternate path to circumvent the fault.

Abstract: A backplane interface adapter for a network switch. The backplane interface adapter includes at least one receiver that receives input cells carrying packets of data; at least one cell generator that generates encoded cells which include the packets of data from the input cells; and at least one transmitter that transmits the generated cells to a switching fabric. The cell includes a destination slot identifier that identifies a slot of the switching fabric towards which the respective input cell is being sent. The generated cells include in-band control information.

Abstract: A device generates a service protection factor (SPFi) for links (N) on a link aggregation group (LAG), determines a traffic allocation bandwidth on the LAG for a service class based on the service protection factor (SPFi) and a congestion guard factor (CGFi), and restricts the traffic allocation bandwidth on the LAG. The service protection factor (SPFi) may guarantee a service availability target in the presence of link failure, and the congestion guard factor (CGFi) may protect against link overload that may arise from imperfectness in traffic load balancing across links in the LAG.

Abstract: An embodiment includes a method of minimizing the delay in convergence time for a complex STP topology following a topology change in the network system in the spanning tree protocol (STP) standard, including: receiving, by a root port of a first bridge, a data message that includes identification of a current root bridge and a priority value of the current root bridge; receiving, by a second port of the first bridge, a second data message from a second bridge; and if a message age timer of the first bridge has less than a limiting message age time value remaining before expiry, then blocking a reply, by the second port of the first bridge, to the second data message from the second bridge.

Abstract: The invention is directed to providing pseudowire tunnel redundancy for VPLS and VLL services in the form of automatic protection switching of the service from a primary pseudowire tunnel to a backup pseudowire tunnel upon detection of a failure affecting the primary pseudowire tunnel. Embodiments of the invention monitor event notifications reported by a network management entity for an indication of a failure affecting the primary pseudowire tunnel; and responsive to detecting the indication, switch a service carried by the primary pseudowire tunnel to the backup pseudowire tunnel. Such event notifications include those corresponding to any of provider edge routers, interface ports, service access points, spokes, and tunnel endpoints that are related to operation of the primary pseudowire tunnel.

Abstract: The invention relates to a rapid response method for the failure of a link between two routing domains in a packet-oriented network. Once the failure of a link has been identified, substitute routes are provided for the interrupted routes by the local selection of alternative routes and by the propagation of messages along the substitute routes. In contrast to conventional inter-domain protocols such as the BGP (Iborder gateway protocol) the transmission of messages and the associated modification to the routing only involves routing domains that lie along the replacement routes. In one embodiment, a network-wide propagation of messages takes place if the failure of the link represents a persistent breakdown. As a consequence, optimal routes are re-determined in the entire network. The invention provides breakdown compensation that is appropriate for temporary breakdowns and prevents instabilities that occur as a result of the use of conventional inter-domain protocols.

Abstract: A method for detecting data frame mode mismatch errors may include receiving a data frame that includes an overhead byte. It may be determined whether a value associated with the overhead byte indicates that a transmitting device operating mode matches a receiving device operating mode. In an additional implementation, it may be determined whether a value associated with the overhead byte indicates that a transmitting device output port matches a receiving device input port. An alarm may be generated when it is determined that the value associated with the overhead byte indicates that either the transmitting device operating mode does not match the receiving device operating mode or the transmitting device output port does not match the receiving device input port.

Abstract: Methods and systems have been provided for pushing critical configuration to a set of network devices. According to various embodiments of the invention, a Network Management Station (NMS) creates a Simple Network Management Protocol (SNMP) context and an SNMP view. Additionally, the NMS specifies a network configuration and a set time period. The NMS pushes the network configuration to the set of network devices. The set of devices apply the network configuration after the set time period.

Abstract: A method and apparatus is disclosed for graceful restart in a multi-process operating system. A transport protocol process, which is capable of restarting independently from the operating system, is executed in a network element. The network element executes a Border Gateway Protocol (BGP) process, which installs one or more routes in a global Routing Information Base (RIB). When the BGP process detects that the transport protocol process has become unavailable, the BGP process keeps the one or more routes in the global RIB even though the transport protocol process is not available.

Abstract: In a 802.15.4 network, each reduced functionality device (RFD) is permitted to communicate with only an assigned full function device (FFD). The present invention allows each of the RFDs to communicate with another RFD upon the RFD determining that the local FFD assigned to the RFD is inoperable or unable to communicate. Under emergency conditions, the RFD is able to communicate with a closely located RFDs such that the closely located RFDs can receive and respond to an emergency situation and/or repeat the message. To satisfy the 802.15.4 standards, communication between the RFDs is allowed only during emergency conditions and when the FFD is inoperative. A comprehensive test procedure is included to insure the integrity of the system is preserved at all times.

Abstract: Systems and methods for testing an implementation of a routing protocol in a device are disclosed. Generally, a sequence of protocol messages is provided and a test is performed to test how a device reacts to a specific playback rate for the sequence of protocol messages, wherein the specific playback rate causes a protocol state transition in the device which differs from an expected protocol state transition absent a specific playback delay.

Abstract: A data communications system may include a network having a plurality of network provider routers configured to support Open Shortest Path First (OSPF) circuits between customer edge routers outside the network, an automated diagnostic system coupled to the network provider routers. The automated diagnostic system may be configured to automatically initiate one or more inquiries of one or more of the network provider routers in response to a customer IP address identifying a customer edge router servicing a customer location from which a service failure has been reported and a circuit address identifying an Open Shortest Path First (OSPF) circuit related to the reported service failure.

Abstract: In a 802.15.4 network, each reduced functionality device (RFD) is permitted to communicate with only an assigned full function device (FFD). The present invention allows each of the RFDs to communicate with another RFD upon the RFD determining that the local FFD assigned to the RFD is inoperable or unable to communicate. Under emergency conditions, the RFD is able to communicate with a closely located RFDs such that the closely located RFDs can receive and respond to an emergency situation and/or repeat the message. To satisfy the 802.15.4 standards, communication between the RFDs is allowed only during emergency conditions and when the FFD is inoperative. A comprehensive test procedure is included to insure the integrity of the system is preserved at all times.

Abstract: A disk storage system containing a storage device having a record medium for holding the data, a plurality of storage sub-systems having a controller for controlling the storage device, a first interface node coupled to a computer using the data stored in the plurality of storage sub-systems, a plurality of second interface nodes connected to the storage sub-systems, a switch connecting to a first interface node and a plurality of second interface nodes to perform frame transfer therebetween based on node address information added to the frame. The first interface node has a configuration table to store structural information for the memory storage system and in response to the frame sent from the computer, analyzes the applicable frame, converts information relating to the transfer destination of that frame based on structural information held in the configuration table, and transfers that frame to the switch.

Abstract: Methods and apparatuses for process a crossconnect switchover in a network element are described. According to one embodiment, an exemplary method includes synchronizing state information regarding broadband subscriber sessions of one or more circuits of a network element between one or more hub devices of an active control card and a standby control card of the network element, and in response to a crossconnect switchover, starting up one or more sessions associated with the one or more hub devices of the standby control card using the synchronized information, such that the one or more sessions are started up as if they are restarted. Other methods and apparatuses are also described.

Abstract: A device detects a signal condition for a link aggregation group (LAG) link, compares the detected signal condition to a signal threshold range, and enables one of a disabled state or a disabled timer state for the LAG link if the detected signal condition is outside the signal threshold range.

Abstract: A system and method for determining an operational status of a segment of a hybrid fiber coax (HFC) cable network. Subscriber premises units (SPUs) connected to the HFC cable network are “pinged” and their responses recorded. The two most responsive SPUs in each node of the HFC cable network are identified. The most responsive SPU is added to a primary ping list and the next most responsive SPU is added to a secondary ping list. The SPUs on the primary list are “pinged” and their responses recorded. If an SPU on the primary list fails to respond, the secondary SPU associated with the node is pinged. If both the primary and secondary SPU associated with a node fail to respond to the “ping,” the node is identified as non-responsive. If all of the nodes associated with a modulator (or a demodulator) are identified as non-responsive, the modulator (or demodulator) is identified as “non-responsive.” Additionally, network devices are pinged and their responses noted.

Abstract: A communication system is described that comprises a switching system, an SCP, and a customer premises. The customer premises includes a remote processor and a plurality of terminating devices. When in operation, the switching system receives a call. Because of the type of call, the switching system queries the SCP for routing information on where to route the call, and the SCP queries the remote processor in the customer premises. The remote processor processes the query to determine routing information to route the call to a terminating device in the customer premises. The remote processor generates a code that includes the routing information and transmits the code to the SCP. The SCP processes the code to identify the routing information determined by the remote processor. The SCP then transmits the routing information to the switching system to cause the switching system to route the call to the terminating device.

Abstract: There is disclosed a reconfigurable network test system. The reconfigurable test system may include a plurality of test modules, a plurality of network interface units, a plurality of bypass units, and a multi-port switch. Each of the network interface units may have a first end and a second end adapted to be connected to a network. Each bypass unit may be in communication with an associated test module, the first end of an associated network interface unit, a first associated switch port, and a second associated switch port. Each bypass unit may have a first mode wherein the associated test module is placed in communication with the first end of the associated network interface unit, and a second mode wherein the associated test module is placed in communication with the first associated switch port and the associated network interface unit is placed in communication with the second associated switch.

Abstract: The present invention provides a method and apparatus for transmitting control signal of Resilient Packet Ring (RPR) Medium Access Control (MAC), including: encapsulating a control signal of RPR MAC interface to be transmitted into an RPR data frame of predefined format, and directly sending it to a receiving unit through a standard interface. In this invention, an RPR data frame of predefined format is utilized to transmit signals between an RPR MAC and a receiving unit, e.g., an RPR client, via standard interfaces, which may avoid the increase of unstable factors affecting signal transmission and hardware cost caused by the appending of hardware devices in the standard interfaces. Thus, the reliability of signal transmission is enhanced, and the hardware cost of communication system is reduced.

Abstract: A method and system for STP-aware subscriber management is disclosed for managing redundant access ports. The STP-aware system includes Access Loop Pairs which provide continuity of subscriber management information in the event of an access port failure. The STP-aware subscriber management system is particularly useful for overcoming the requirements for extra ports within Link Access Group configured access networks known in the art.

Abstract: A mobile radio communication system and method of initiating a circuit-switched service at a mobile station over a System Architecture Evolution (SAE) core network using packet-switched communications between the mobile station and the SAE core network is provided. The method includes communicating service handling information between a Mobile Switching Centre (MSC) and the mobile station through a Mobility Management Entity (MME) of the SAE core network; sending instructions from the MSC for setting up the circuit-switched service through a Media Gateway, coupled to at least one network external to the SAE core network; providing packet-switched addressing information for the Media Gateway to the mobile station; and initiating the circuit-switched service at the mobile station over the SAE core network and through the Media Gateway.

Abstract: A method and system for testing a Telephony User Interface is disclosed. Voice prompts of the Telephony User Interface are converted into tone prompts that are representative thereof. Each tone prompt can have a predetermined frequency and/or duration, so that it is readily recognizable by a Telephony User Interface tester. Thus, automation of the testing of Telephony User Interface is enhanced.

Abstract: A redundancy protection scheme comprises sending a protection packet from the primary network interface to the secondary network interface, the protection packet having a hardware address of the primary network interface as a source address and a hardware address of the secondary network interface as a destination address. The scheme further comprises determining whether the secondary network interface receives the protection packet from the primary network interface, operating the primary and secondary network interface as active and standby network interface in response to the secondary network interface receiving the protection packet, or operating both the primary and secondary network interface as active network interface in response to the secondary network interface not receiving the protection packet, and providing the hardware address of the active secondary network interface to devices coupled thereto.

Abstract: A system and method for verifying the integrity of a communication link in a wireless optical communication network. The system and method include monitoring the communication link on at least two levels and enabling or disabling signaling over the communication link appropriately depending on events reported through the system.

Abstract: A method implemented in a computer infrastructure having computer executable code having programming instructions tangibly embodied on a computer readable medium. The programming instructions are operable to configure an initiator-to-initiator message route in a switched fiber channel arbitrated loop (FCAL) network such that the initiator-to-initiator message route traverses a replacement field replaceable unit (FRU). Additionally, the programming instructions are operable to transmit a verification initiator-to-initiator message along the initiator-to-initiator message route to verify proper operation of the replacement FRU.

Abstract: A disk storage system containing a storage device having a record medium for holding the data, a plurality of storage sub-systems having a controller for controlling the storage device, a first interface node coupled to a computer using the data stored in the plurality of storage sub-systems, a plurality of second interface nodes connected to the storage sub-systems, a switch connecting to a first interface node and a plurality of second interface nodes to perform frame transfer therebetween based on node address information added to the frame. The first interface node has a configuration table to store structural information for the memory storage system and in response to the frame sent from the computer, analyzes the applicable frame, converts information relating to the transfer destination of that frame based on structural information held in the configuration table, and transfers that frame to the switch.

Abstract: There is described a communication structure for at least two solar inverters, having a transmission medium by means of which each of the at least two solar inverters is connected to a communication network with a first group of the solar inverters each being connected via an LAN interface to the communication network, and with a further group of the solar inverters being connected to the first group via serial interfaces. Two different network types are therefore provided with the first being suitable for standard LAN technologies with rapid data transmission over short distances, and with the second being suitable for interference-insensitive data transmission over long distances.

Abstract: Methods and apparatus for efficiently allowing protection switch information to be communicated on bidirectional lines are disclosed. According to one aspect of the present invention, a method for communicating protection switch information from a first network element to a second network element across bidirectional links that include at least one working line and a protection line involves obtaining a generic framing procedure GFP frame at the first network element. The GFP frame has a payload area with a client payload field. The method also includes defining a command field associated with the GFP frame that is in the payload area but not in the client payload field, and storing protection switch information in the command field.

Abstract: A method and apparatus for measurement of service disruption interval is described. The apparatus may include may included a setting component, a generating component, a first output component, a receiving component, a service disruption start time designator, a settling start time designator, a settling period designator, a service disruption end time designator, a service disruption interval designator, a second output component, and a memory component. In general, a test set consistent with the described embodiments may continuously send test traffic through a network under test (“NUT”) and monitor the traffic output from the NUT. The test set may be configured to detect the start of a service disruption and to detect when the service disruption has been cleared. Based on these two pieces of information, the test set may determine and report a service disruption interval.

Abstract: A system for monitoring performance parameters relating to a user network interface (“UNI”) in a communication network is provided. The system comprises a message source parser module, a translator module, and a message recording module. The message source parser module is operative to examine an exception message sent by a network element in the communication network. The message source parser module is also operative to determine which network component the message relates to. The translator module is operative to determine if the message is related to one or more UNIs in the network. The message recording module is operative to post information from the message to one or more data records that correspond to the one or more UNIs identified by the translator module.

Abstract: The invention relates to a method for tolerating the breakdown and/or decoupling of at least one network node in a communication network used for controlling and/or adjusting the movement of a plurality of machine parts, for example the rotation bodies in a printing machines, machine tools and other production machines, wherein the network is operated according to a closed single or multiple ring structure, in which each node communicates with the transmitter or the port of a first adjacent node by means of a receiver or a first port and with the receiver or the port of a second adjacent network node by means of a transmitter or a second port, the closed ring structure is preserved in the case of the breakdown or decoupling of at least one node, at least one network node is coupled to the network by means of a data path switching device which is actuated, in the case of the breakdown or decoupling of said node, in such a way that the communicating nodes, which exist in the network and are arranged next to eac

Abstract: A method and a computer program product for detecting link status in a blade system are provided. The method and computer program product provide for generating a first pattern of characters at a server blade of the blade system, transmitting the first pattern of characters from the server blade to an Ethernet switch of the blade system, and comparing a second pattern of characters to the first pattern of characters to determine whether a link from the Ethernet switch to a network is active in response to the server blade receiving the second pattern of characters from the Ethernet switch.

Abstract: A test system comprising: acquiring an upstream channel descriptor list; entering a pause network state when the upstream channel descriptor list is completed; and selecting a particular channel from the upstream channel descriptor list before exiting the pause network state.

Abstract: The system and method get a packet trace for a failed communication and a packet trace for a successful communication. The two packet traces are generated with packets from a common protocol(s) shared by the two communications. The failed and successful communications have at least some network elements in common. A field(s) in the common protocol(s) is identified. The field(s) is updated to be the same in both packet traces. The two packet traces are then compared to produce a list of remaining differences that can be used to diagnose problems in the failed communication. The list can also be compared to bills of materials for the failed and successful communications to further enhance diagnosis of the failed communication.

Abstract: A packet-based traffic switching system with error detection and correction without taking the system offline. The system tests offline paths without interfering with other online paths. Also, the system tests online paths even while no data cell traffic is sent over the paths. The system responds to the addition or removal of paths or path components without interrupting cell traffic. The system detects and selectively flushes defective paths without impacting paths that are working properly. The system initializes new switching fabrics automatically without using software to set values. Thus, the system tests online paths and corrects errors without going offline.

Abstract: In an embodiment, a network service provider (NSP) operates a provider network to provide VPN services to its customers. A VPN links various customer sites allowing customers to send data between these sites over the NSP network. Each site network includes a customer edge router (CE) while the provider network includes a plurality of provider edge routers (PEs) to communicate with the CEs. The PEs include virtual routing address (VRFs), and the PEs and CEs include interfaces (IFs). A database stores information related to the relationships between the network components (e.g., VPNs, PEs, CEs, VRFs, IFs, etc.), and a management software package (MSP) has access to the database. When a fault occurs, the MSP, based on collected information and information in the database, determines the impacted network components. Other features include classifying the seriousness of the network's faults and representing different faults by a color scheme.

Abstract: A monitoring system gathers both site-to-site measurements, and agent-to-agent measurements, wherein one or more agents are distributed in one or more sites in a distributed network environment. Site-to-site measurements between two sites, such as site one and site two, are obtained by testing between any agent at site one and any agent at site two. A measurement rate between sites and between agents is determined that allows for the detection of events, such as user perceivable events, without overwhelming the set of agents that form the distributed measurement system. With, for example, a scheduling mechanism used to schedule measurement tests of finite duration, as opposed to continuous streams of measurement packets, for each pair of agents, the test can be used as an indication as to whether the measurement system is overwhelmed.

Abstract: An ATM multiplexing apparatus of the present invention is the apparatus for selectively performing cell discard processing in the case of congestion on the basis of a use state of the same connection formed by cells from the side of an ATM switching unit and subscribers without installing UPC units, and the ATM multiplexing apparatus, which is connected to the ATM switching unit and each of plural subscribers through ATM communication lines and performs multiplexing processing to ATM cells sent from the plural subscribers, comprises: detection means 118 for detecting a level of a congestion state corresponding to the received ATM 157 from the subscribers; and discard means (111, 115 and 117) for selectively discarding the received ATM cells from the subscribers on the basis of a communication state determined by the received ATM cells 155 from the ATM switching unit and the received ATM cells from the subscribers and a level value of a warning signal 129 indicating the detected congestion state.

Abstract: A low-cost, high-speed data switching system and method uses several parallel switching systems or fabrics. In one of various embodiments, for example, the constituent data flows in a data stream can be selectively routed to a switching fabric that has the lowest input data rate. Data flows can be assigned to the various switching fabrics so as to balance the amount of data passing through each parallel system. Data flows can be re-assigned on an as-needed basis to insure maximum throughput. In the case where a data flow initially routed into one switching fabric must be re-routed to a different fabric, the ordering of data packets can be preserved by withholding the transfer of packets through the second fabric until the packets previously sent into the first fabric have cleared. Methods and apparatus of the present invention find application to parallel computing as well.

Abstract: An apparatus is disclosed which according to an embodiment is configured to store a direct tunnel context. The direct tunnel context comprises a field or flag indicating whether or not a direct tunnel is established between the apparatus and a radio network, and further comprises at least one of a tunnel endpoint identifier and an address of a user plane of a serving node. The direct tunnel context optionally further comprises at least one of a tunnel endpoint identifier and an address of a user plane of a controller of the radio network. The apparatus may be a gateway or a gateway general packet radio service support node. The invention further provides a method, system, device and program suitable or configured to handle such direct tunnel contexts.

Abstract: A first device transmits messages to a second device. The first device keeps track of messages that have already been transmitted from the first device to the second device, experiences an interruption in transmission of messages at the first device, and resumes the transmission from the first device following the interruption. Resuming the transmission includes transmitting only messages that have not already been completely transmitted from the first device to the second device.

Abstract: The invention is directed to providing a method and system for automatically determining a root cause of a failure in a packet switching telecommunications network using IP/MPLS protocols and having Virtual Private Network (VPN) services such as VLL, VPLS, VPRN.

Abstract: A network hardware device of the invention includes a reception section receiving data from a network, and outputting a reception completion signal, a timer section measuring a preset time, and a delay section generating an interrupt signal so as to notify a host CPU of completion of the reception. When the timer section does not measure a time, the delay section generates an interrupt signal upon reception of the reception completion signal. On the other hand, when the timer section measures a time, upon reception of the reception completion signal, the delay section generates an interrupt signal after the timer section measures a preset time.

Abstract: An improved mechanism for analysing connection establishment/teardown process or identifying failure points (i.e. nodes) in a PNNI network through the use of a novel debug IE (information element) that is propagated along the communication path for a given connection to activate diagnostic functions on targeted switching devices. The mechanism comprises a method that is initiated by embedding a debug information element (IE) in a data packet that is propagated to various switching devices (the nodes) along the communication path. The debug IE is encoded such that it will be recognized by selected switching devices along the path, but ignored by other non-selected switching devices. Further encoding identifies targeted switching devices that are suspected to be possible failure points to confirm that they are functioning properly.

Abstract: A packet transmission diagnostic system transmits diagnostic packets during a communications session in which data packets are transmitted between a source and destination. The diagnostic packets elicit responses from routers along a path between the source and destination. The elicited responses, in the form of packets, are used by the diagnostic system to produce one or more packet-delivery metrics for one or more of the routers along a packet transmission path between the source and destination.

Abstract: The network switch is configured to enable monitoring of switched data. The network switch includes a housing and one or more port cards. Each port card has one or more physical ports and includes switching circuitry to selectively create a communication path between two physical ports. The network switch also includes packet analyzer circuitry, situated within the housing, to monitor data packets switched via a communication path between two physical ports without substantially degrading signal integrity of the data packets.

Abstract: A fault isolation system and method. A hierarchical numbering system is applied to devices within a subscriber network. The number system comprises a continuously concatenated string that provides a relative location of each active device with a subscriber network. The numbering system provides “genealogical” information about network devices and their location with the network and facilitates the correlation of non-responsive CPE data with faults in network devices.

Abstract: A first multi protocol label switching (MPLS) enabled Internet Protocol (IP) data network is able to transmit data to a second MPLS enabled IP network via a legacy optical network, which would not otherwise be able to handle the user network interface (UNI) protocols required to be used within an MPLS network environment, by means of configuring the legacy optical network and its traditional network management system (TNMS) so that they simulate or emulate an MPLS enabled optical network. The simulation/emulation of an MPLS network is performed as follows: when a first legacy network element (NE) receives a connection request (a UNI request) from the MPLS network under a UNI protocol, the UNI request is passed to the TNMS, which then sets the required connection across the legacy network via a second edge NE to an NE of the second IP network.

Abstract: The technology disclosed includes a software architecture for methods and devices used to test routers, switches and the like, particularly high volume infrastructure devices. In particular, this architecture associates test data stream definitions with emulated devices that send test frames or packets to and receives them from a system or device under test (“DUT”). By relating the test data stream definitions to definitions of the emulated devices that are coupled to the DUT, automation of test frame and/or test packet design improves, especially where some of the information needed to generate test frames and/or packets is dynamically generated during a test.