Caspian Networks, Inc.

Netexpress Systems, Inc.

Saisei Networks, Pte Ltd.

Other

Dsc Communications Corporation

Sable Networks, Inc.

Anagran, Inc.

Lawrence G Roberts

Alex E Henderson

John Harper

P Kingston Duffie

Faizel Lakhani

Alex Henderson

I C Wilkinson

Tricci Y So

Dennis L Hunt

John A McBrayne

Fredrick L Drain

Gary G Croke

Frederick L Drain

A system, method and computer program product are provided. In use, a plurality of flows associated with packets destined for an output port is identified. A utilization associated with the output port is further measured. Thus, rates of a plurality of the flows destined for the output port may be individually controlled at an input port thereof, based on the utilization to ensure that the utilization remains less than 99.9% and avoid buffering more than 400 packets with a correspondingly low delay.

System, method, and computer program product for controlling output port utilization

A system, method and computer program product are provided for controlling the rate of a network flow. In use, a rate of a network flow is monitored. In addition, it is determined whether the rate exceeds a threshold. Further, at least a portion of the network flow is conditionally discarded or marked, based on the determination.

System, method, and computer program product for controlling the rate of a network flow and groups of network flows

A router system, method and computer program product are provided. In use, a flow request is received. In addition, the flow request is processed based on one of a plurality of preferences using a single measurement and/or a single computation. Further, the one preference is associated with the flow request.

System, method, and computer program product for processing flow requests based on an associated preference using a single computation

New switching technology relies upon state information for providing a previously unavailable degree of quality of service. In particular, by providing the ability to give service guarantees to uniquely identifiable sets of packets ('micro-flows'), different qualities of service can be offered for each transmission. The QoS associated with each micro-flow is characterized by a set of descriptors. These descriptors are communicated to each switch by the first packet of the micro-flow associated with the descriptors.

Micro-flow management

A mechanism for recovering from a failure in a network is disclosed, wherein a first set of information, such as a first packet, is initially sent from a source to a destination via a first route. As the packet travels along the first route, if a failure is detected somewhere along the route, a message is directed back to the source to inform it of the first route failure. In response to the message, the source reroutes one or more future packets intended for the destination to an alternate route rather than the first route. By doing so, the source routes around the failure to ensure that future packets will not be sent via the failed route. In addition, the source resends the first packet to the destination via the alternate route. By doing so, the source prevents the information from the first packet from being lost. By resending packets in this manner, the failure recovery mechanism makes it possible to not lose information during the recovery process.

Network failure recovery mechanism

An invention is provided for affording an aggregate micro-flow having intelligent load balancing. Initially, a set of label switched paths (LSPs) is defined for a network domain. Then, as the network receives a set of data packets, a micro-flow comprising the set of data packets is defined. In addition to the information included in each received data packet, the micro-flow includes a quality of service (QoS) type. A particular label switched path (LSP) is selected from the defined set of LSPs, based on the QoS type of the micro-flow, and the micro-flow is transmitted along the selected LSP.

Micro-flow label switching

A method and system performs parallel processing of asynchronous processes on ordered entities. A system focuses on the average time and variance of the variable time process. Each processor can run multiple contexts. The processing may be divided into a number of stages, each of which can be performed by each of the processors. A system also needs to ensure that the order of the entities is preserved as desired. This order may be maintained by performing some type of pre-processing on the entities to determine their order, and then not starting processing on an entity until the processing of any entity which must precede that entity has been completed. For processing of packets in a network, it may be needed to ensure that packets in the same flow maintain their order after processing. A system also may determine the number of processors that optimally are needed in order to process an incoming stream of entities at a desired speed. This computation may depend on how many different contexts each processor runs. In addition, this computation also may depend on whether there is an input buffer available to store the incoming entities, and the capacity of such an input buffer.

Parallel network processor array

New switching technology relies upon state information for providing a previously unavailable degree of quality of service. In particular, by providing the ability to give service guarantees to uniquely identifiable sets of packets (&ldquo;micro-flows&rdquo;), different qualities of service can be offered for each transmission. The QoS associated with each micro-flow is characterized by a set of descriptors. These descriptors are communicated to each switch by the first packet of the micro-flow associated with the descriptors.

Call information is transmitted between broadband switching modules (12) and a broadband services switch (10). Each broadband switching module (12) receives call information from outside the broadband services switch (10) and translates the information into asynchronous transfer mode (ATM) cells. Each broadband switching module (12) also generates a route setup cell and a route teardown cell in order to establish and release a connection path to another broadband switching module (12), respectively. The broadband switching module (12) sends the route setup cell, that includes a virtual circuit identifier identifying the connection path for the calling information ATM cells, along a dedicated VCI to an intermediary broadband switching module (12). The sending broadband switching module (12) then transmits the payload ATM cells containing the calling information immediately after transmitting the route setup cell and before receiving an indication that a connection path has been established. The payload ATM cells are transmitted along a payload VCI determined by the broadband switching module (12) which was placed within the route setup cell.

Apparatus and method of transmitting call information prior to

Bit-mapped and compressed image data are converted one another through an intermediate image data or code form wherein each image is represented by a list of sublists, each sublist being itself a list of numerical values representing run lengths transistions from one type of picture element (pel) to a second and opposite type of picture element (pel) (e.g., a black pel and a white pel). Hence the intermediate code data structure according to the invention is termed a transition list or TL code or data structure. The data structure and coding rules are defined by rules relating to code type, code word length and code word interdependence. A specific conversion process specifies that the transition list be composed of sublists wherein each represents a scan line. The preferred form of intermediate code is a fixed word-length transition list, that is, a serial list of values representing run lengths of either 'black' picture elements or 'white' picture elements stored serially in digital data format having a fixed word length.

Method and apparatus for manipulating image data employing an

An apparatus for selecting a reference line for image data compression including a plurality of mutually connected reference selector chips for selecting a reference scan line from vertical mode coding of image data. The reference selector chips select a reference scan line from a plurality of preceding scan lines in exclusive or combination of the image data of each candidate reference scan line with the image data from the input scan line. The candidate reference scan line that has the lowest number of dissimilar bits is selected as the reference scan line. Each candidate reference scan line has associated therewith a register having bit positions arranged from the highest order bit position to a lowest order bit position for storing a binary sum of the number of dissimilar bits. When the sums are compared, the binary value and successive bit positions are compared from the highest order bit position to the lowest order bit position. When the binary value for a compared bit position of a register is greater than the binary value in the corresponding bit position of another register, each reference selector chip generates a losing signal for indicating that the register lost the arbitration. When the lowest order bit position of a register is not greater than the lowest order bit position of any other register and no losing signal was generated for the register, the associated chip generates a winning signal for indicating which candidate reference scan line had the least number of bits dissimilar to the corresponding bits in the input scan line. Each chip further includes a circuit for establishing a priority among the candidate reference scan lines so that two registers both having the smallest binary sum will not create a deadlock.

Apparatus for selecting a reference line for image data compression

A method and apparatus for improving the performance of data compression processes, such as relative address coding, CCITT standard facsimile processes, and similar two-dimensional image coding processes, by block coding one or more of the vertical mode codes produced by these processes. The performance of data compression processes is improved by representing one or more sequences of vertical mode code words with a single block code word. A reference scan line is preferably selected from among a plurality of previous scan lines, for example, the immediately preceding ten scan lines, for two-dimensional image coding. The previous scan line which is most similar to the current scan line to be coded is selected as the reference scan line. The selected reference scan line is then fed with the current scan line to be coded to a two-dimensional data compression coding process so as to yield a first tier of data compression. The image data are preferably checked during the two-dimensional data compression coding process for a predetermined run of a given vertical mode code, and a preselected block code is substituted if the predetermined run of the given vertical mode code appears so as to yield a second tier of data compression. Preferably, eleven consecutive vertical offset zero code words are represented by a single block code word. This provides enhanced data compression and reduces the amount of image data stored or transmitted and concomitantly lowers the cost for operation of the image data storage or transmission apparatus.

Method and apparatus for block coding vertical mode codes for enhanced

A method and apparatus for selecting a reference scan line for two-dimensional image coding preferably compatible with known facsimile transmission equipment are disclosed. Selection of a reference scan line in accordance with the method and apparatus of the invention allows data compression for facsimile transmission so that the cost for use of the communication link is reduced. More than one previous scan line is considered as a candidate reference scan line. A reference scan line is selected from among a plurality of previous scan lines, for example, the immediately preceding ten scan lines. The preselected or adaptively selected scan line among the multiple prior scan lines, more particularly, the previous scan line which is most similar to the current scan line to be coded, is selected as the reference scan line. The reference scan line is then fed with the current scan line to be coded to a two-dimensional data compression coding process so as to yield optimum data compression. This reduces the amount of image data transmitted and lowers the cost of operation of the facsimile transmission apparatus. The method and apparatus are particularly effective for compressing image data representing screened pictorial images.

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Woodside, CA, United States of America

Lawrence G Roberts