Abstract: Method and devices are provided to form virtual switches for data networks. As noted above, the term “switch” as used herein will apply to switches, routers and similar network devices. Each virtual switch acts as a single logical unit, while encompassing at least two physical chassis. Accordingly, each virtual switch may be treated as a single point of management. Each virtual switch includes a master chassis and at least one slave chassis. The master chassis is configured to control the slave chassis. The master chassis includes at least one master supervisor card and the slave chassis includes at least one slave supervisor card. The master chassis and the slave chassis communicate via a virtual switch link according to a virtual switch link protocol.

Abstract: According to the present invention, methods and apparatus are provided to allow efficient switching of frames for transmission between a Layer 2 Virtual Local Area Network such as a Metro Ethernet Network and an external network. Reserved inner tags are used to identify particular services. In one example, inner tags allow mapping of frames associated with a particular subnetwork onto a particular virtual circuit associated with an ATM network.

Abstract: Methods and apparatus are disclosed for maintaining netflow statistics using an associative memory to identify and maintain netflows. A lookup operation is performed on a set of associative memory entries to produce an associative memory result directly or after a subsequent memory read operation. In response to the associative memory result corresponding to a not found condition, an entry is added to the set of associative memory entries. Otherwise, a statistics entry in the set of statistics is updated based on the associative memory result. In one implementation, the associative memory is programmed with a set of permanent netflow entries and a set of dynamic or nonpermanent netflow entries, which are maintained in the form of a queue or ring buffer. In one embodiment, when the number of dynamic entries exceeds a threshold value, one or more of the dynamic entries and their corresponding statistics values are flushed.

Abstract: First and second partially filled ATM cells are removed from a cell stream and merged into a third ATM cell. The third ATM cell may then be inserted back into the cell stream. The third ATM cell may include header information indicative of the number of partially filled ATM cells from which it was created. To accommodate these operations, a data communication device, such as an ATM switch, is configured to identify partially filled ATM cells within an ATM cell stream. The device is also configured to merge at least two of the partially filled ATM cells into a merged ATM cell and to insert the merged ATM cell back into the ATM cell stream. Identifying partially filled ATM cells may involve use of a lookup table stored in a computer readable medium and indexable using logical connection identification information. The scheme can be used on a link-by-link basis within an ATM network or across multiple hops within such a network for combining cells traveling along a common route.

Abstract: A communication system (500) includes a plurality of subscriber systems (510) coupled to a plurality of twisted pair data lines (520). Each subscriber system (510) has an availability guarantee value, which may specify a level of service for the subscriber system (510). A communication server (502) is coupled to the plurality of subscriber systems (510). The communication server (502) selectively couples a subscriber system (510), responsive to a request for service, to either a first modem pool (530) or a second modem pool (540) based on the availability guarantee value associated with the subscriber system (510). Communication server (502) can also provide a soft-termination state and dynamic network address allocation for subscriber systems (510).

Abstract: A two-wire bus is used to de-skew XAUI lanes of a single charnel received at independent chips. One wire of the bus is transmits an alignment signal generated by a master and used by slaves coupled to the bus to detect misalignment of their data from data received at the master. The other wire transmits an error signal generated by any slave that detects a misalignment.

Abstract: A method for conveying data communications network management information to an umbrella management system whereby network management information events are published on an information bus and received at a subscribing monitor interface located on the information bus. The monitor interface then converts the network management information events into umbrella management system-useable information and communicates the umbrella management useable information to the umbrella management system. In this manner, the umbrella management system is able to import valuable information pertaining to the devices and services that comprise the overall network. The monitor interface includes an adapter located on the information bus that subscribes to network management information events, a converter that formats the network management information events into data useable by the umbrella management system, and a forwarder that communicates the umbrella management system-useable data to the umbrella management system.

Abstract: A method and apparatus for implementing Quality of Service (QoS) policy in a data communications network. A content addressable memory (CAM) contains flow information for each active flow of packets passing through a given node of a data communications network. The CAM has associated with each entry a packet counter, a byte counter, a token bucket, and a contract value. Each flow is assigned one of a plurality of output queues and optionally at least one output threshold value. An access control list CAM (ACLCAM) contains masked flow information. The ACLCAM provides an index to internal token bucket counters and preconfigured contract values of an aggregate flow table which becomes affected by the packet statistics. In this way, flows are aggregated for assignment of output queues and thresholds, possible dropping, and possible modification of packets.

Abstract: A method and apparatus are provided for recognizing and accessing telephone numbers from a Web page. In the preferred embodiment of the invention, an HTML code of an accessed Web page is parsed and converted. A parsing algorithm applied to the text in the HTML document pattern-recognizes telephone numbers. Coding is added to iconify the recognized telephone numbers. The user's Internet-capable telephone displays the iconified telephone numbers. All previously-active links and graphical displays supported by the Internet-capable telephone are maintained in this display. To call a phone number, the user selects the icon, and the Internet-capable phone determines how to initiate the call. For a two-line phone, the Internet-capable telephone initiates a telephone call to the selected number. For a one-line phone, the Internet-capable telephone determines whether the line is available for a call. If the line is not currently being used, the Internet-capable telephone initiates a voice call to the selected number.

Abstract: Methods and apparatus are disclosed for matching a string with multiple lookups using a single associative memory, such as, but not limited to binary and ternary content-addressable memories (CAMs). In one implementation, an information string is partitioned into multiple segments. A first lookup operation is performed on the associative memory using the first segment to produce a first associative memory result, which is used as input to a memory lookup operation to produce a first result. The first result can be programmed to have any desired value or length. This first result along with a second segment of the information string is then used as input to the same associative memory to produce a second associative memory result, which is typically used as input to a memory lookup operation to produce a second result. This process can be repeated for an arbitrary or predetermined number of times.

Abstract: A communication system formed by a private network that includes a private wireless network. The communication system includes a public wireless network using a public wireless protocol, such as GSM, and includes public networks, such as PSTN, ISDN and the Internet, using a wired protocol, such as 1P. The private network also includes a local area network (LAN) and the private network connects to the public networks using a wired packet protocol, such as IP. The public and private wireless networks operate with the same public wireless protocol, such as GSM, and the private wireless network additionally operates with a wired packet protocol, such as IP. The communication system permits users to operate freely in both public and private wireless networks using standard mobile stations while achieving high private network data rates. The communication system uses normal wireless handsets or other mobile or fixed stations without need for any modifications.

Abstract: A method of performing maintenance on a network access server having associated channels carrying incoming digital or analog traffic determines whether maintenance is needed on a network access server and then communicating a busy condition of any unused associated channel from the network access server to the service request switch. Used channels are monitored for existing calls and when the used channel becomes substantially unused as indicated by defined digital and analog signaling protocol a busy condition is communicated from the network access server to the service request switch. An unused channel may be determined by usage falling below a predetermined threshold. Any remaining, existing calls are migrated to other network access servers. A signal is then sent to indicate that maintenance on the network access server can be performed and any new request arriving during a busy condition of the network access server are routed to another network access server.

Abstract: A method and apparatus for implementing Quality of Service (QoS) policy in a data communications network. An active flow content addressable memory (CAM) contains entries of flow information for each active flow of packets passing through a given node of the data communications network. The CAM has associated with each entry a packet counter, a byte counter, a token bucket, and a contract value. Each flow is assigned one of a plurality of output queues and optionally at least one output threshold value. A token bucket algorithm is employed on each flow to determine whether packets from that flow exceed the contract value. Such packets may be dropped or optimally modified to reflect an alternate output queue and/or alternate threshold before being sent to the selected output queue for transmission from the node.

Abstract: An assembly, method, and device for high-speed optical format data transmission includes a printed circuit board containing mounting locations for electrical components, optical components, and a heatsink device. A tray may also be mounted on the printed circuit board to route optical fiber to various components. The heatsink is positioned at a predetermined height above the printed circuit board so that it physically contacts the electrical and optical components that require cooling. The printed circuit board may include one or more openings in which one or more of the electrical or optical components that are significantly taller than the other components are embedded. The heatsink may also include one or more openings in which one or more of the taller electrical or optical components are positioned.

Abstract: A method for providing advanced intelligent network (AIN) supplementary services between an ITU H.323 endpoint and a service control point (SCP) having service logic programs (SLPs) and transaction capabilities applications part (TCAP) protocol support is described. The method preferably includes providing an ITU H.450 interface in the SCP, the ITU H.450 interface being capable of communicating with the ITU H.323 endpoint, and utilizing an ITU H.225 FACILITY message and an ITU H.450 application protocol data unit (APDU) to carry one or more of call-related information, operation codes and AIN messages between the ITU H.323 endpoint and the SCP. In a case in which the AIN supplementary services are not related to an existing ITU H.323 call, the ITU H.225 FACILITY message is empty. Alternatively, in a case in which the AIN supplementary services are related to an existing ITU H.323 call, the ITU H.225 FACILITY message is one of a variety of user-to-user information elements (UUIEs).

Abstract: Internet protocol (IP) performance monitoring method and apparatus generate a timing probe data to be sent over the network, the timing probe data packet containing at least a send time of day (STOD) stamp for a sender of the timing probe data packet. The timing probe data packet is sent over the network from the sender to a receiver. The timing probe data packet contents including at least the STOD stamp are analyzed as a performance measure of the network. After sending and before analyzing, data including at least a receive time of day (RTOD) stamp is written into the probe data packet at the receiver, and probe data packet is echoed by the receiver. In this way, the probe packet sender performs the analysis based upon the STOD stamp and the RTOD stamp.

Abstract: The invention provides a way to fallback to a PSTN call at any time during a VoIP call when Quality of Service in a VoIP network falls below some acceptable level. The PSTN fallback calls can be retrieved “midcall” and rerouted back over the VoIP network. This provides optimal utilization of VoIP without sacrificing the quality of the call connection. Calls are cheaper because PSTN fallback calls are only established temporarily for the amount of time that the QoS problem exists on the VoIP network. Call fallback is conducted in a VoIP gateway by first receiving an incoming call. A Voice over IP (VoIP) call is established for the incoming call over the VoIP network. VoIP packets are encoded from the voice signals in the incoming call and sent over the VoIP network. Quality of service of the VoIP network is monitored during the VoIP call and a fallback call is setup over a PSTN network at any time during the VoIP call when the monitored quality of service of the VoIP network degrades.

Abstract: A delay measurement technique according to an embodiment according to the present invention is based on the precept, ascertained by the inventors, that a link between network nodes will often contribute to the delay encountered between several different pairs of network nodes. Such a technique identifies the path between each pair of nodes by a list of links that form the path. Paths that are orthogonal are treated as being necessary for describing the delays encountered between nodes, and, once the requisite set of orthogonal paths has been derived, all other paths can be described in terms of one or more of these orthogonal paths. Such a technique also lends itself to matrix representation of the paths, and the use of matrix manipulation techniques in deriving delay and jitter.

Abstract: A cluster of alternate gatekeepers handles the load of a single logical zone. The alternate gatekeepers exchange signals among each other according to a special cluster protocol. Each alternate gatekeeper may be connected and exchange signals with endpoint devices.

Abstract: An EMI shield, or module cage, mounts to a circuit board such that a first portion of the module cage extends above a first planar surface of the circuit board and a second portion of the module cage extends below a second planar surface of the circuit board. The module cage surrounds a corresponding transceiver module and allows airflow to travel across the transceiver module and through the module cage in a direction substantially perpendicular to a planar surface of the circuit board to cool the transceiver module. In one arrangement, multiple module cages attach to the circuit board in a modular configuration. Such a configuration allows attachment, to the circuit board, of the number of module cages corresponding to the number of transceiver modules required or utilized by the circuit board.