Spirent Communications, Inc.

Argosystems, Inc.

William Thomas Hatley

Thomas R McBeath

Jocelyn Kunimitsu

Craig Fujikami

Paul L Master

Carl Uyehara

Roy Liang Chua

Walter J Scheuermann Ii

Jon Kanji Otaguro

Margaret J Goodman

Various aspects of the disclosed technology relate to the generation for test purposes of test traffic, in a manner compliant with advanced flow control.

Methods and apparatuses for enhanced transmission selection-capable simulated traffic generation

Some aspects of the technology relate to the generation for test purposes of test packet ingredients by a microprocessor, ongoing with the generation for test purposes of test packets incorporating the test packet ingredients by a high-speed FPGA. Some aspects of the technology relate to the generation of outgoing test packets incorporating the test packet ingredients, at a programmable logic device such as an FPGA. These aspects are implemented as an apparatus, a method, computer readable medium, and a data structure.

Methods and apparatuses for generating network test packets and parts of network test packets

Embodiments of the invention relate to generating simulated network traffic. In some embodiments, simulated network traffic may be generated using a specification of a sequence of frames to be transmitted from the network testing device. The specification may specify at least two frames including a first frame and a second frame. The specification may further specify a first interframe gap associated with the first frame and a second interframe gap, having a different length from the first interframe gap, associated with the second frame. In some embodiments, the specification may specify an interframe gap for each frame in the sequence of frames. This information may be used to determine the relative transmit time of each frame to be transmitted. Because the specification identifies an interframe gap for each frame in the sequence, in some embodiments, multi-frame burst network traffic may be generated.

Methods and apparatus for generating simulated network traffic

Information is added to an encapsulated payload in a data field of a frame subsequently to placing a checksum into a checksum field of a header encapsulating the payload, wherein the checksum has been determined from byte values of the header and the payload, yet having the checksum remaining detectable as valid upon interpretation of the header and the payload. A signature field that contains the information is inserted into the data field. The signature field has a checksum cheater subfield. A one's complement of a checksum determined from byte values of the information is then placed into the checksum cheater subfield. Accordingly, the checksum in the checksum field of the header remains valid.

Signature field in a latency measurement frame

Timestamp information can be placed in a frame that includes a first portion processable at a selected layer of a protocol stack and a second portion processable at a lower protocol layer of the protocol stack subsequently to the processing of the first portion, wherein the first portion is contained within the second portion and wherein a numerically computed error detection code for the second portion is computed during processing of the second portion. A timestamp signature having a timestamp subfield of initialized data and a corrector subfield of initialized data is embedded in the first portion during processing thereof at the selected protocol layer. A numerical constant functionally equivalent to the numerically computed error detection code is determinable from the initialized data in the timestamp subfield and the corrector subfield. The data in said timestamp subfield is modified with timestamp information subsequently to processing of the second portion at the lower protocol layer. The data in the corrector subfield is then modified such that the numerical constant as determinable from the modified data in the timestamp subfield and the corrector subfield remains unchanged, whereby the numerically computed error detection code computed at the lower protocol layer remains valid.

Method and apparatus for placing a timestamp in a frame

Processor methods and apparatus for adaptable network processing having speed advantages often associated with hardware implementations of network processing code or logic, as is often achieved using ASICs, for example, but at the same time having reconfigurability advantages often associated with software implementations of this code or logic. Methods and apparatus are described for adaptable hardware devices, such as a field programmable gate array (FPGA) or a circuit using FPGAs, to execute network processing code or logic. Methods and apparatus are described for using a software based device to program adaptable hardware devices to implement desired network processing code or logic.

Growing community of inventors

San Jose, CA, United States of America

William Thomas Hatley