Ixia

Keysight Technologies Singapore (Holdings) Pte. Ltd.

Michael D Hutchison

Earl Chew

Chiat Earl Chew

Christopher M Kowalski

Gerald Raymond Pepper

Noah Steven Gintis

Robert Brian Luking

Laura Choy

Tom Keddie

Lai Fun Choy

A method for transmitting and coherently detecting data transmitted over electrical lanes that experience different amounts of skew includes, at a traffic generation or forwarding device, self calibrating transmit and receive-side components of the traffic generation or forwarding device to account for skew between electrical lanes and setting per-electrical lane delays based on the calibration. Data to be transmitted to a network device is generated. The data to be transmitted is spread, using one of the transmit-side components, over a first number of electrical lanes. The data is multiplexed from the electrical lanes onto a second number of optical lanes, the second number being different from the first number. Data is transmitted to and received from the network device over the optical lanes. Transmitted data is reconstructed from the received data using the receive-side components.

Methods, systems, and computer readable media for providing traffic generation or forwarding device that compensates for skew between electrical lanes in a manner that allows coherent detection of transmitted data

Methods, systems, and computer readable media for precise measurement of switching latency of packet switching devices are disclosed. One method includes steps implemented in a network equipment test device including at least one processor. The method includes transmitting frames to a device under test. The method further includes receiving one of the transmitted frames from the device under test. The method further includes determining a measured latency of the device under test based on a difference between a time that the one frame was transmitted to the device under test and a time that the one frame was received from the device under test. The method further includes determining an indication of backlog latency of the device under test caused by the device under test inserting a virtual lane marker in traffic transmitted to the network equipment and reporting the indication of the backlog latency.

Methods, systems, and computer readable media for precise measurement of switching latency of packet switching devices

There are disclosed a system, a test head and a method for testing a device under test. Two or more test heads may be mated directly with respective connectors on the device under test. Each test head may include a traffic generator including a stateless packet builder to generate stateless traffic for transmission to the device under test, and a traffic receiver including a stateless packet analyzer to accumulate traffic statistics on stateless traffic received from the device under test. A server coupled to the two or more test heads via respective communications links, may generate stateful traffic for transmission to the device under test by the two or more test heads, and may process stateful traffic received from the device under test by the two or more test heads.

Distributed network test system

Methods and test systems for reporting transmit bandwidth contention. A histogram representing transmit bandwidth demand for a network device may be built, the histogram including a plurality of bins representing for a plurality of contiguous time intervals of equal duration including a current time bin and plural future time bins. The histogram may be displayed and periodically updated.

Measuring and displaying bandwidth contention

An impairment unit and method of emulating network impairments is disclosed. The impairment unit may receive network traffic and transmit impaired network traffic. Received packets may be stored in a memory physically partitioned into a plurality of memory blocks and logically partitioned into a plurality of buffers. At least one buffer may be associated with each of a plurality of predefined impairment classes. One or more buffer may be a limited-length queue. Memory blocks may be assigned to buffers on an as-needed basis. A classifier may determine respective impairment classes of the received packets. A number of memory blocks assigned to each limited-length queue may be limited to a respective predetermined maximum. An enqueue manager may store each received packet and associated metadata in the buffer associated with the respective impairment class. The enqueue manager may discard received packets if the associated limited-length queue is full.

Network impairment unit for concurrent delay and packet queue impairments

An impairment unit, method, and machine readable storage media for emulating network impairments. A first network interface may receive network traffic including a plurality of received packets. A classifier may determine an impairment class of each received packet based on test information contained within a payload portion of each received packet, the impairment class of each received packet being one of a plurality of impairment classes, each impairment class uniquely associated with a corresponding one of a plurality of impairment profiles. An impairment engine may impair each of the plurality of impairment classes in accordance with the corresponding impairment profile to provide impaired network traffic. A second network interface may transmit the impaired network traffic to the network.

Traffic item impairment emulation

An impairment unit, method, and machine readable storage media for emulating network impairments. An impairment unit may include a network interface to receive network traffic from a network and to transmit impaired network traffic to the network. An impairment engine may generate the impaired traffic based on the received network traffic, the impaired network traffic including at least some duplicate packets. The impairment engine may determine a bandwidth available for transmission of duplicate packets based on the received network traffic and may constrain the total length of the duplicate packets to fit within the available bandwidth.

Network impairment unit with bandwidth-constrained packet duplication

An apparatus to generate test traffic for testing a network. A scheduler may provide packet definition data for a sequence of packets, each packet associated with a respective flow control group. A channelized schedule FIFO (first-in first-out) queue may store the packet definition data. The channelized schedule FIFO queue may include multiple parallel channels, each channel dedicated to storing packet definition data associated with a corresponding flow control group. A plurality of non-channelized packet builder lanes may build packets in accordance with packet definition data read from the channelized schedule FIFO. A channelized output FIFO buffer may store packets built by the plurality of packet builder lanes. The channelized output FIFO buffer may include multiple parallel channels, each channel dedicated to storing packets associated with a corresponding flow control group. An output multiplexor may interleave packets from the channelized output FIFO buffer to form the test traffic.

Parallel traffic generator with priority flow control

Impairment units and methods for impairing network traffic. An impairment unit may receive packets from a network and determine an impairment class of each packet from a plurality of impairment classes. Input logic may determine whether or not each received packet will be reordered. A received packet not to be reordered may be stored in a normal traffic FIFO queue uniquely associated with the impairment class of the received packet. A received packet to be reordered may be stored in a reorder traffic FIFO queue uniquely associated with the impairment class of the received packet. Output logic may select a sequence of packets from head ends of the plurality of normal traffic FIFO queues and the plurality of reorder traffic FIFO queues to provide outgoing traffic. A transmitter may transmit the outgoing traffic to the network.

Growing community of inventors

Richmond, CA, United States of America

Michael D Hutchison