Abstract: The invention provides a device (D2) for reducing ingress noise in a digital signal, comprising a noise predictor (20) for predicting an amount of ingress noise in the digital signal (sn) based on past samples of the ingress noise, and a subtractor (21) for subtracting the predicted amount of ingress noise from the digital signal. Channel distortion is compensated for by a noise-independent equalizer (25), such as a ZF equalizer, placed upstream of the noise predictor (20). The device (D2) may be incorporated, for example, in a cable modem termination system (CMTS) of an hybrid fiber/coax (HFC) network.

Abstract: A network device may manage communication sessions with clients so that attempts at the client to automatically keep the session alive can be ignored for purposes of timing out the session. The device may examine resource requests received from the client as uniform resource locators (URLs) and determine whether the URLs include a context variable. The device may determine whether to reset a timeout period for the communication session based on a presence of the context variable in the URL. At the client side, the context variable may be attached to URLs that are part of functions configured to automatically access the network device.

Abstract: A compression device recognizes patterns of data and compressing the data, and sends the compressed data to a decompression device that identifies a cached version of the data to decompress the data. Both the compression device and the decompression device cache the data in packets they receive. Each device has a disk, on which each device writes the data in the same order. The compression device looks for repetitions of any block of data between multiple packets or datagrams that are transmitted across the network. The compression device encodes the repeated blocks of data by replacing them with a pointer to a location on disk. The decompression device receives the pointer and replaces the pointer with the contents of the data block that it reads from its disk.

Abstract: A system for managing a circular buffer memory includes a number of data writers, a number of data readers, a circular buffer memory; and logic configured to form a number of counters, form a number of temporary variables from the counters, and allow the data writers and the data readers to simultaneously access locations in the circular buffer memory determined by the temporary variables.

Abstract: A method of carrying out arbitration in a packet exchanger including an input buffer temporarily storing a packet having arrived at an input port, and a packet switch which switches a packet between a specific input port and a specific output port, includes the steps of (a) concurrently carrying out a first plurality of sequences in each of the sequences basic processes for at least one of the input buffer and the output port are carried out in a predetermined order, and (b) making an allowance in each of the sequences for packets to be output through output through output ports at different times from one another.

Abstract: A first-in-first-out (FIFO) queue optimized to reduce latency in dequeuing data items from the FIFO. In one implementation, a FIFO queue additionally includes buffers connected to the output of the FIFO queue and bypass logic. The buffers act as the final stages of the FIFO queue. The bypass logic causes input data items to bypass the FIFO and to go straight to the buffers when the buffers are able to receive data items and the FIFO queue is empty. In a second implementation, arbitration logic is coupled to the queue. The arbitration logic controls a multiplexer to output a predetermined number of data items from a number of final stages of the queue. In this second implementation, the arbitration logic gives higher priority to data items in later stages of the queue.

Abstract: A router receives a packet at an ingress interface. The router classifies the received packet based on at least a first field value contained in the header of the packet. According to the classification of the received packet, the router associates one of the plurality of forwarding tables to the packet. The router then performs a lookup operation in the associated forwarding table according to at least a second field value contained in the header of the packet. Based on the lookup operation, the router determines an egress interface and transmits the received packet from the determined egress interface.

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 network device is configured to receive a registration message from a private user device including a private internet protocol (IP) address associated with the private user device. A public IP address and discrete port number are assigned to the private user device and private IP address and stored in an incoming call table. The registration message is translated to include the public IP address and discrete port number. The registration message is forwarded to a proxy server for registration. An incoming call invitation message is received from a public user device, where the call invitation message is directed to the public IP address and discrete port number associated with the private user device. The call invitation message is translated to include the private IP address associated with the private user device based on the received public IP address and discrete port number and the incoming call table. The call invitation message is forwarded to the private user device.

Abstract: A switch fabric includes input links, output links, and at least one switching element. The input links are configured to receive data items that include destination addresses. At least some of the data items have different priority levels. The output links are configured to output the data items. Each of the output links is assigned multiple ones of the destination addresses. Each of the destination addresses corresponds to one of the priority levels. The switching element(s) is/are configured to receive the data items from the input links and send the data items to ones of the output links without regard to the priority levels of the data items.

Abstract: A network router includes a set of interface cards to receive packets from a network, and a set of accounting modules to calculate flow statistics for the packets. The router further includes a control unit to adaptively update routing information in response to the calculated flow statistics, and to route the packets in accordance with the routing information. The control unit identifies potentially malicious packet flows for the received packets based on the flow statistics, and applies an intercept filter to intercept the packets of the identified packet flows. The control unit analyzes the intercepted packets in real-time to determine the presence of a network event, and updates the routing information based on the determination, e.g., by terminating routing for packets associated with malicious packet flows. In this manner, the router may adaptively respond to network events, such as network security violations.

Abstract: A system includes a group of devices and a shared memory that is partitioned into blocks that are capable of being allocated to the group of devices using linked lists. The system also includes check logic configured to store a group of bits, where each bit corresponds to one of the blocks, and counter logic configured to count for a predetermined period of time. The system further includes logic configured to clear the group of bits stored in the check logic, cause the counter logic to count for the predetermined period of time, monitor a de-allocation of the blocks in the shared memory, set, for each of the blocks that is de-allocated during the predetermined period of time, the corresponding bit in the check logic, identify, after the predetermined period of time, one or more bits that have not been set, and mark the blocks corresponding to the one or more bits as available for allocation.

Abstract: An ATM switch allowing simplified OAM processing only on the line incoming side is disclosed. An incoming line circuit has a header conversion table storing information indicating whether the system is an end point of an OAM processing flow for each connection and an OAM table storing an AIS flag and an RDI flag for each connection. As for an OAM cell found by referring to these tables to be forced to go back to its own port, an switch output port number is rewritten in the OAM function section. In addition, in the case of an AIS cell, the function type is rewritten so as to become an RDI cell. In the case of an LB cell, the LB indication is rewritten so as to become a return LB cell, and switching to its own port is conducted in the ATM switch core.

Abstract: Techniques for modifying a script portion of markup language documents are described. By modifying the script portion of markup language documents, access to resources residing on remote servers through an intermediate server is facilitated. The script portions can be modified at the intermediate server, client devices, or both.

Abstract: In general, this disclosure relates to techniques for allowing multiple clients to concurrently configure a network device. More specifically, a management module creates a working copy of an initial data source that stores configuration data for a network device and modifies the working copy to reorder one or more configuration objects in a list in response to configuration commands from a client. Upon receiving a show|compare command or a commit command, the management module generates a configuration patch that is a textual representation of any differences between the working copy and the initial data source. The configuration patch includes modification control indicators that identify configuration objects in the list that are reordered. The patch is applied to the initial data source to reorder the list of configuration objects within the initial data source without processing portions of the configuration data associated with the reordered configuration.

Abstract: GPRS Tunneling Protocol (“GTP”) packets are intercepted by receiving a GTP tunnel packet, determining whether the GTP tunnel packet is to be intercepted, intercepting GTP tunnel packets if it is determined that the GTP tunnel packet is to be intercepted, and processing the intercepted GTP tunnel packets. Multiple tunnels may be intercepted simultaneously and GTP tunnel packets from different tunnels may be processed differently. Implementations include both inline and offline interception of GTP traffic between SGSN and GGSN.

Abstract: A method and apparatus for scheduling virtual upstream channels within one physical upstream channel is disclosed. A different MAP message is received by a receiver for each virtual upstream channel from that sent downstream. Where multiple upstream receivers are used, separate MAP messages can be sent for each receiver and consequently, each virtual upstream channel. The use of multiple upstream receivers is not necessary if the upstream receiver can change the upstream channel descriptors it is using per burst.

Abstract: In general, techniques are described for reducing response times to retrieve content in an intermediate network device. In particular, the intermediate network device receives a packet from a client device of a first network that requests content from a remote network device of a second network, inspects the packet to determine whether the requested content has been previously cached to either of a first and a second memory of the device, issues a request to load the requested content from the second memory to the first memory based on the determination and queues the packet within in the queue. After queuing the packet, the intermediate network device then processes the packet to assemble a response that includes the content from the memory.

Abstract: A subscriber network system is provided that is capable of reducing response time and reducing device cost. In the subscriber network system, a control cell is received that includes an ID portion, a data portion, and a cyclic redundancy check (CRC) portion. The control cell is processed in cooperation with a virtual path identifier (VPI), where the processing obtains the ID portion and the CRC portion. The ID portion and the CRC portion are processed and the ID portion is compared to a first stored value and the CRC portion is compared to a second stored value to produce information. A cell is produced to include the information and the produced cell is used to facilitate a connection in a network.

Abstract: A toolbar that is provided or inserted in a markup language document so as to facilitate features or functionality provided by a server is disclosed. The toolbar is able to determine whether the toolbar should be displayed as part of the markup language page being displayed. In one embodiment the server is an intermediary server.