摘要:
In a method of identifying matching packets at different locations in a network, a first plurality of packets is received at a first location in the network, and a first subset thereof is selected in accordance with a filter. A second plurality of packets is received at a second location in the network, and a second subset thereof is selected in accordance with the same filter. Each packet in the first and second subsets is parsed to extract invariant header fields from an outermost IP header inwards, until a minimal set of invariant header fields is obtained for that packet, or until it is determined that a minimal set is not obtainable for that packet. A packet signature is computed from the minimal set for each packet having a minimal set, and the packet signatures are compared to identify matching packets in the first and second subsets.
摘要:
A method of providing topology information about a network to a topology manager is disclosed. The network includes a plurality of sensors each having a sensor ID, and the method includes performing the following steps at each of the plurality of sensors: receiving a stream of packets and identifying a topology trace packet in the stream of packets, wherein the topology trace packet has a destination address and an ID of a previous sensor, including the sensor ID in the topology trace packet, sending the topology trace packet to the destination address, forming a report message so as to include the sensor ID, the previous sensor ID, sending the report to the topology manager; and, providing network addresses of adjacent nodes to the topology manager.
摘要:
In the methods and devices of the present disclosure, a dummy compensation word is added to the data packet such that the UDP checksum value need not be modified from any previous value, regardless of changes to the UDP payload. Because the UDP checksum value is not modified in embodiments of the present disclosure, there is no delay waiting for a UDP checksum value to be calculated and no need for additional buffers to store the data packet contents because of UDP checksum calculations. The dummy compensation word is calculated so that the unmodified value maintained in the checksum is the checksum for the data packet including the dummy compensation word. By placing the compensation word in the data packet after the last word in the UDP payload, there is no, or very minimal, processing delay and data packet buffering hardware is significantly reduced.
摘要:
A programmable transceiver for a network element includes a programmable circuit including internal logic and control logic. Interfaces connect the programmable circuit to a network and a network element. The control logic facilitates programming of the internal logic responsive to an in-band program signal while the programmable circuit services network traffic received via at least one of the interfaces.
摘要:
In a printed article, pigment flakes are magnetically aligned so as to form curved patterns in a plurality of cross-sections normal a continuous imaginary line, wherein radii of the curved patterns increase along the imaginary line from the first point to the second point. When light is incident upon the aligned pigment flakes from a light source, light reflected from the aligned pattern forms a bright image which appears to gradually change its shape and move from one side of the continuous imaginary line to another side of the continuous imaginary line when the substrate is tilted with respect to the light source.
摘要:
An optical filter, a sensor device including the optical filter, and a method of fabricating the optical filter are provided. The optical filter includes one or more dielectric layers and one or more metal layers stacked in alternation. The metal layers are intrinsically protected by the dielectric layers. In particular, the metal layers have tapered edges that are protectively covered by one or more of the dielectric layers.
摘要:
The invention relates to bi-directional long-cavity semiconductor lasers for high power applications having two AR coated facets (2AR) to provide an un-folded cavity with enhanced output power. The lasers exhibit more uniform photon and carrier density distributions along the cavity than conventional uni-directional high-power lasers, enabling longer lasers with greater output power and lasing efficiency due to reduced longitudinal hole burning. Optical sources are further provided wherein radiation from both facets of several 2AR lasers that are disposed at vertically offset levels is combined into a single composite beam.
摘要:
An optically variable device may be manufactured by aligning magnetic flakes on a surface of an adhesive layer by applying the flakes onto the adhesive layer surface in presence of a magnetic field, and curing the adhesive layer having magnetic flakes adhered to the adhesive layer. When cured, the adhesive layer holds the magnetic flakes oriented, enabling subsequent encapsulation of the oriented magnetic flakes in a coating layer on the adhesive layer, without a substantial loss of orientation of the magnetic flakes.
摘要:
A signal leakage in a cable network may be detected by using a test device to obtain a spectrum of an electromagnetic wave propagating in vicinity of the cable network, and automatically detecting QAM channels in the obtained spectrum by detecting characteristic spectral roll-offs at boundary frequencies between QAM channels of the cable network. A test device may be used to determine which QAM channels are currently active on the cable network, thereby facilitating automatic QAM signal leakage detection.
摘要:
A network testing device may be linked to a dedicated remote server e.g. a could-based server having a unique, pre-determined address. The testing device may be configured to cease operating, become locked or limited in testing functionality after a number of startup cycles, days of use, a certain date, etc. Once the testing device is locked, the testing device may be re-activated only by establishing a connection to the server. A database of network testing devices currently in use may be provided. Once a testing device is lost or stolen, the database may be remotely updated to prevent reactivation of that testing device, so as to render the lost or stolen testing device useless for an unauthorized operator of the testing device.