Abstract: Traffic generators, methods, and computer readable storage media for testing a network are disclosed. A scheduler may determine a sequence of packets to be transmitted, each packet in the sequence of packets belonging to one of a plurality of flow control groups. A packet generator may generate packets in the determined sequence and output completed packets for transmission over a network under test. The packet generator may include a first processing engine and a last processing engine configured as a pipeline to perform respective sequential stages of a packet generation process, and a first bank of first-in-first-out (FIFO) queues including a plurality of FIFO queues corresponding to the plurality of flow control groups. The first processing engine may store first packet forming data associated with each flow control group in the corresponding FIFO queue of the first bank of FIFO queues.

Abstract: A method and system for measuring a convergence time of a network. Test traffic including a plurality of packet groups may be transmitted and received via the network. The network may be instructed to redirect packets belonging to a selected packet group from a first port of the network to a second port of the network. A first test port unit coupled to the first port may determine an arrival rate for the selected packet group and store a below threshold timestamp when the arrival rate first falls below a predetermined threshold rate. A second test port unit coupled to the second port may determine an arrival rate for the selected packet group and store an above threshold timestamp when the arrival rate first equals or exceeds the predetermined threshold rate. The convergence time may be determined based on the below threshold timestamp and the above threshold timestamp.

Abstract: Apparatus, method, and storage medium for testing a network. A network card may include four transmit engines and four receive engines to respectively generate and process packets at a data rate of 10 GHz. The network card may be configured in a first mode to also include four 10 GHz network interface units coupled to respective ones of the four 10 GHz transmit engines and the four 10 GHz receive engines. The network card may be configured in a second mode to also include a coherent multiplexer to combine packets generated by the four 10 GHz transmit engines into test traffic at a 40 GHz data rate, a packet distribution engine to accept packets at a 40 GHz data rate and distribute the accepted packets between the four 10 GHz receive engines, and a 40 GHz network interface unit coupled to the coherent multiplexer and the packet distribution engine.

Abstract: Methods, traffic receivers, and computer readable storage media for testing network connections are disclosed. A traffic receiver coupled to a network under test may receive a packet. A packet group identification number (PGID and a sequence number (SN) may be extracted from the received packet. Data associated with the PGID may be retrieved from a memory, the data including a next expected sequence number (NESN), a start of run (SOR), a number of in-order packets (NIO) and a number of duplicate packets (NDP). When SN is equal to NESN, NESN and NIO may be incremented. When SN is less than NESN and SN is greater than or equal to SOR, NDP may be incremented. When SN is greater than NESN, SOR may be set to SN, NESN may be set to SN plus one, and NIO maybe incremented. Updated data may be stored in the memory.

Abstract: Traffic generators, methods, and computer readable storage media for testing a network are disclosed. A scheduler may determine a sequence of packets to be transmitted, each packet in the sequence of packets belonging to one of a plurality of flow control groups. A packet generator may generate packets in the determined sequence and output completed packets for transmission over a network under test. The packet generator may include a first processing engine and a last processing engine configured as a pipeline to perform respective sequential stages of a packet generation process, and a first bank of first-in-first-out (FIFO) queues including a plurality of FIFO queues corresponding to the plurality of flow control groups. The first processing engine may store first packet forming data associated with each flow control group in the corresponding FIFO queue of the first bank of FIFO queues.

Abstract: Methods, systems, and computer readable media for generating test packets in a network device using value lists caching are disclosed. In one method, value lists are stored in dynamic random access memory of a network test device. Each value lists includes values for user defined fields (UDFs) to be inserted in test packets. Portions of each value lists are read into per-port caches. The UDF values are drained from the per-port caches using per-port stream engines to generate and send streams of test packets to one or more devices under test. The per-port caches are refilled with portions of the value lists from the DRAM and a rate sufficient to maintain the sending of the stream engine packets to the one or more devices under test.

Abstract: Port units, methods, and computer readable storage media for testing a network are disclosed. A traffic generator may generate and transmit test traffic over a network under test, the test traffic including a plurality of interleaved packet streams, each traffic stream associated with one of a plurality of flow control groups. A traffic receiver may receive flow control packets from the network under test. The traffic generator may be configured to stop transmission of all packet streams associated with one or more paused flow control groups when the traffic receiver receives a flow control packet identifying the one or more paused flow control groups.

Abstract: There is disclosed a method of capturing packets and packet receivers to capture packets. A plurality of packets may be received form a network. A timestamp may be attached to each received packet. The timestamped received packet may be distributed among a plurality of capture engines. Each of the plurality of capture engines may store, in a respective capture memory of a plurality of capture memories, at least some timestamped received packets determined to match one or more of a plurality of predetermined capture criteria. A list in timestamp order of contiguous packets stored in the plurality of capture memories may be prepared.

Abstract: An apparatus and machine readable storage medium for performing a binary search of an ordered list containing 2N values, where N is an integer greater than one. The apparatus may include a pipeline having N stages numbered 1 to N in sequence. Stage M of the pipeline, where M is in integer from 1 to N, may include a memory storing 2M-1 values from the ordered list, a comparator to compare the key to a value read from the memory based on comparison results from previous stages in the pipeline, and a result storage register to store a comparison result from the comparator and the comparison results from the previous stages in the pipeline.

Abstract: A method and system for measuring a convergence time of a network. Test traffic including a plurality of packet groups may be transmitted and received via the network. The network may be instructed to redirect packets belonging to a selected packet group from a first port of the network to a second port of the network. A first test port unit coupled to the first port may determine an arrival rate for the selected packet group and store a below threshold timestamp when the arrival rate first falls below a predetermined threshold rate. A second test port unit coupled to the second port may determine an arrival rate for the selected packet group and store an above threshold timestamp when the arrival rate first equals or exceeds the predetermined threshold rate. The convergence time may be determined based on the below threshold timestamp and the above threshold timestamp.

Abstract: Apparatus, method, and storage medium for testing a network. A network card may include four transmit engines and four receive engines to respectively generate and process packets at a data rate of 10 GHz. The network card may be configured in a first mode to also include four 10 GHz network interface units coupled to respective ones of the four 10 GHz transmit engines and the four 10 GHz receive engines. The network card may be configured in a second mode to also include a coherent multiplexer to combine packets generated by the four 10 GHz transmit engines into test traffic at a 40 GHz data rate, a packet distribution engine to accept packets at a 40 GHz data rate and distribute the accepted packets between the four 10 GHz receive engines, and a 40 GHz network interface unit coupled to the coherent multiplexer and the packet distribution engine.

Abstract: There are disclosed an apparatus, a machine readable media, and methods for testing a network. The apparatus may include a statistics engine coupled to a memory. The statistics engine may extract a packet group identifier (PGID) from a packet received from the network and retrieve traffic statistics associated with the PGID from the memory. The retrieved traffic statistics may include a packets-per-interval count and a packets-per-interval threshold, the packets-per-interval count indicating a number of packets received within a time interval of a sequence of time intervals. At the start of each new time interval, the statistics engine may set a flag indicating whether or not the packets-per-interval count for the previous time interval was equal to or greater than the packets-per-interval threshold. The flag may be saved in the memory as part of the traffic statistics associated with the extracted PGID.

Abstract: There is disclosed a scheduler for a traffic generator and a method of scheduling traffic. A working memory may stores N respective timer values for N count-down timers, where N is an integer greater than one. An arithmetic and logic unit (ALU) may update each timer value in rotation every N cycles of a clock. A temporal interpolator may delay output data from the ALU by a selectable delay period of 1 to N cycles of the clock.

Abstract: Methods, traffic receivers, and computer readable storage media for testing network connections are disclosed. A traffic receiver coupled to a network under test may receive a packet. A packet group identification number (PGID and a sequence number (SN) may be extracted from the received packet. Data associated with the PGID may be retrieved from a memory, the data including a next expected sequence number (NESN), a start of run (SOR), a number of in-order packets (NIO) and a number of duplicate packets (NDP). When SN is equal to NESN, NESN and NIO may be incremented. When SN is less than NESN and SN is greater than or equal to SOR, NDP may be incremented. When SN is greater than NESN, SOR may be set to SN, NESN may be set to SN plus one, and NIO maybe incremented. Updated data may be stored in the memory.

Abstract: There are disclosed an apparatus, a machine readable media, and methods for testing a network. The apparatus may include a statistics engine coupled to a memory. The statistics engine may extract a packet group identifier (PGID) from a packet received from the network and retrieve traffic statistics associated with the PGID from the memory. The retrieved traffic statistics may include a packets-per-interval count and a packets-per-interval threshold, the packets-per-interval count indicating a number of packets received within a time interval of a sequence of time intervals. At the start of each new time interval, the statistics engine may set a flag indicating whether or not the packets-per-interval count for the previous time interval was equal to or greater than the packets-per-interval threshold. The flag may be saved in the memory as part of the traffic statistics associated with the extracted PGID.

Abstract: Port units, methods, and computer readable storage media for testing a network are disclosed. A traffic generator may generate and transmit test traffic over a network under test, the test traffic including a plurality of interleaved packet streams, each traffic stream associated with one of a plurality of flow control groups. A traffic receiver may receive flow control packets from the network under test. The traffic generator may be configured to stop transmission of all packet streams associated with one or more paused flow control groups when the traffic receiver receives a flow control packet identifying the one or more paused flow control groups.

Abstract: There is disclosed a method of capturing packets and packet receivers to capture packets. A plurality of packets may be received form a network. A timestamp may be attached to each received packet. The timestamped received packet may be distributed among a plurality of capture engines. Each of the plurality of capture engines may store, in a respective capture memory of a plurality of capture memories, at least some timestamped received packets determined to match one or more of a plurality of predetermined capture criteria. A list in timestamp order of contiguous packets stored in the plurality of capture memories may be prepared.

Abstract: There is disclosed a method of capturing packets and packet receivers to capture packets. A timestamp may be attached to each packet received from a network. Each timestamped packet may be routed to a capture engine of a plurality of capture engines. Each of the plurality of capture engines may save at least some packets determined to match one or more of a plurality of predetermined capture criteria. A list of contiguously captured packets in time-stamp order may be prepared.

Abstract: A traffic generator may include a scheduler to provide packet forming data defining a packet; a background engine to retrieve a packet template, the packet template including a first checksum mask, a first pre-sum, and a first address; a fill engine to generate content for variable-content fields of the packet for a payload portion of the packet in accordance with the packet forming data and the packet template; and a checksum engine. The checksum engine may include an accumulator that calculates a payload checksum for the payload portion of the packet and first logic circuits that compute a first checksum based on the first pre-sum, the first mask, and at least some of the payload checksum and the variable-content fields. Insertion logic may insert the first checksum into the packet at a position indicated by the first address.

Abstract: There is disclosed a scheduler for a traffic generator and a method of scheduling traffic. A working memory may stores N respective timer values for N count-down timers, where N is an integer greater than one. An arithmetic and logic unit (ALU) may update each timer value in rotation every N cycles of a clock. A temporal interpolator may delay output data from the ALU by a selectable delay period of 1 to N cycles of the clock.