3183 results about "Timestamping" patented technology

The present invention includes a client computer, a first server computer, and a second server computer. The first server provides an authorization ticket containing a time stamp to the client computer when the client computer is authorized to access the first server. An elapsed time counter is started at the client computer when access is provided to the first server. When a request is received at the client computer to access the second server, the client computer determines the session length based upon the elapsed time counter. The client computer calculates a hash value for the authorization ticket, the session length, and a secret shared with the second server computer. The client computer transmits a login request to the second server including the authorization ticket, the session length, and the hash. The second server decrypts the authorization ticket and retrieves a copy of the shared secret. The second server executes a hash function on the authorization ticket, the session length, and the shared secret. The second server then compares the computed hash to the hash value received from the second client application. If the two hash values are identical, the second server retrieves the time stamp from the authorization ticket and adds the session length to the time stamp. The second server then compares the resulting value to the current time. If the resulting value and the current time are within a preset threshold value, the client computer is provided.

Remote frequency synchronization is achieved between two or more nodes in a packet-switched network using differential timestamps. A line is fit to multiple differential time values using a minimum delay principle. Frequency synchronization and/or absolute time synchronization between the two nodes may be achieved using one or both of uplink and downlink differential time values and fitting one or both of first and second lines to differential time values by different means of the minimum delay principle.

Mechanisms and methods for traversing trees are disclosed. A novel data structure for modeling a node that includes a unique node counter also is described. In certain embodiments of the inventions the unique node counter is a timestamp of sufficient granularity to render each timestamp in the tree unique. A node counter, in conjunction with the lineage of a specified continuation node may be used to locate an appropriate starting point within a tree in a continuation call when the specified continuation node no longer exists in the tree.

The invention provides an effective recording and playing method and system. The recording and playing method and system are characterized in that in an online teaching process or an online meeting, operation of functions of multimedia whiteboard by a user, speech/voice of the user, communication voice with other users and/or tutoring voice and the like are recorded to respectively form different data streams; and a united timestamp can be generated by an online teaching system to mark various data streams rather than completely recording the whole event in a form of streaming media so that network users can conveniently download various data steams which need to be played via a network from a Cloud server or a local area network server anytime anywhere; after obtaining the data streams, clients of user terminals can obtain the data streams on line according to the timestamp and organically combine and play the data streams to the users, thus finishing the on-demand browsing.

An apparatus comprising a first circuit and a second circuit. The first circuit may be configured to embed one or more timestamp chunks into a compressed bitstream in response to one of a video data signal and an audio data signal. The second circuit may be configured to generate an output signal in response to decoding the compressed bitstream. Each of the one or more timestamp chunks comprises an error correction mechanism configured to detect and correct errors on the compressed bitstream prior to decoding the compressed bitstream.

The location of unmodified wireless assets in a wireless communication network may be identified using time differences of arrivals of a communication sequence at different network receivers. Time-stamping devices may include correlator circuits in parallel with signal decoders to time-stamp communication sequences. Cellular wireless networks may be frequency-multiplexed to increase spatial time-stamping density. Tags may be attached to passive assets to provide location identification information to network devices. Locations of assets broadcasting standard 802.11 radio frequency structures may be identified. Noise inherent in correlating a communication sequence may be reduced by using a selected correlation function.

A method is provided that includes: receiving a plurality of estimated position points, each estimated position point including a timestamp, where each estimated position point is an estimate of a position of a vehicle at a time respective timestamp; receiving on or more path events, where each of the one or more path events includes a timestamp and data from at least one sensor of the vehicle; generating a path from the plurality of estimated position points, where the estimated position points are arranged in order of ascending time represented by the respective timestamp; and interpolating between two of the estimated position points to determine a location corresponding to one of the one or more path events, where the timestamp of the one of the one or more path event corresponds to a time that is between the times represented by the timestamps of the two estimated position points.

A mechanism for ensuring the physical location of data processing devices as a security check is provided. With this mechanism, security data is transmitted to data processing devices via an electrical network and is used to perform a security check to determine if the data processing device may operate. The data processing devices may be limited such that they may only power-up, boot-up, or remain operational when they are coupled to the electrical network. Thus, they must be physically located such that they may gain access to the electrical network. In addition, a security check may be used to control which data processing devices may communicate data packets with one another over the data network. When a data packet is received by a data processing device, security data in the data packet is compared against a local history of security data received by the recipient of the data packet via the electrical network. If matching security data is found in the history for the same time represented by an associated timestamp, then the sending data processing device and the receiving data processing device are determined to be present on the same electrical network and may communicate with one another.

The invention requests to protect a time synchronization method applicable to a wireless sensor network and relates to a wireless network communication technology. The time synchronization method comprises the steps: time source equipment generates beacon frames and broadcasts and sends the beacon frames periodically; non-time source equipment obtains time stamps in the transmitting and receiving process of the beacon frames, obtains frequency deviation and time deviation of an equipment clock and a time source equipment clock according to calculation of a plurality of collected time stamps, compensates a local clock and realizes synchronization with a time source; and time synchronization is carried out step by step, and finally the time synchronization of the whole network is realized. Considering the application environment of the equipment and different requirements for time synchronization, a multi-stage and multilevel synchronization mechanism for combining broadcast synchronization, matching synchronization and monitoring synchronization is adopted. The non-time source equipment can apply synchronization of time synchronization command frames according to different requirements, the equipment without applying the time synchronization command frames can monitor and receive the time synchronization command frames similarly and finish synchronization, so that the whole communication overhead and energy consumption of the network are reduced and the normal operation of the network is guaranteed.

A method and system for controlling data delivery and reception, which alleviate the processing workloads imposed on management systems and reduce the hardware and software resources required in management systems. Each time a status message arrives from network subsystems, a data storage unit in a management system stores the received information, together with a reception timestamp. At regular intervals, or on an on-demand basis, a data requesting unit in a terminal station issues a data delivery request message to the management system, including a reception time specification to qualify the data records to be delivered. In response to the request, a data retrieval unit in the management system searches its local data storage to extract the requested data records whose reception timestamps are not earlier than the given reception time specification. The data records found are then supplied to a data transmission unit. The data transmission unit delivers them to the requesting terminal station, affixing a transmission timestamp. In the requesting terminal station, a timestamp storage unit saves the transmission timestamp received, while a reception processing unit applies a series of processing operations to the received message to make it suitable for the terminal station.

A method for measuring and reporting performance parameters in a network having at least one originator for generating test protocol data units, and multiple reflectors for relaying the test protocol data units along successive segments of a test path in the network. The method generates the test protocol data units at the originator and transmits the test protocol data unit along a test path that includes multiple reflectors. Each reflector relays the test protocol data unit to the next reflector along the test path. Measurements of performance parameters are collected from the multiple reflectors in the test protocol data unit by inserting timestamps into the test protocol data unit at the originator and each of the reflectors to identify the departure and arrival times for each test protocol data unit at the originator and each of the reflectors in both the downstream and upstream directions along the test path.

A computer-implemented method is described for authenticating an identity of a user requesting execution of a computerized transaction via a first client computing device. The first device and a second client computing device in proximity each execute applications for communicating with a server. The first and second devices contemporaneously capture voice sequences including at least one audible sound vocalized by the user, and a timestamp indicating when the sound is captured. The identity of the user is validated based upon a determination that the user vocalized the pass phrase, and a difference between the first timestamp and the second timestamp is below a predetermined threshold. The first device executes a computerized transaction with the server computing device upon receiving validation of the identity of the user.

The invention discloses a time synchronization method for a wireless sensor network. The method comprises the following steps of: generating a synchronous data packet, and marking a transmission timestamp in the synchronous data packet; transmitting the synchronous data packet to a child node; receiving the synchronous data packet, and marking a receiving timestamp in the synchronous data packet; and compensating for the clock drift of the child node according to the transmission timestamp and the receiving timestamp in the synchronous data packet. By the time synchronization method and the time synchronization system for the wireless sensor network, clock drift compensation between a parent node and the child node is realized only by transmitting the synchronous data packet to the child node to realize regional time synchronization in a region formed by the parent node and the child node, and compared with conventional all-network time synchronization, the regional time synchronization reduces network energy consumption and also can avoid the energy consumption caused by crosstalk interference as much as possible.

The invention relates to a method for realizing sub-microsecond synchronization accuracy based on a PTP (Precision Time Protocol), belonging to the technical field of communication; in order to obtain high-accuracy synchronization efficiency and save hardware investment cost, the method comprises the following steps: before a master time sends synchronization messages, synchronizing a clock and a clock source of an Ethernet transceiver; obtaining average path delay of links by a delay request information packet delay measuring mechanism or measuring a waiting delay information packet delay measuring mechanism; and performing asynchronous correction on the links so as to realize sub-microsecond synchronization accuracy. In the method, the DP83640 Ethernet transceiver is adopted, network message time stamp can be exactly obtained, the PTP protocol on an AT91RM9200 platform is realized, and sub-microsecond synchronization accuracy can be realized. Via test, the synchronization accuracy can be up to 100ns; and the whole system is low in cost, excellent in openness and expandability, and easy to implement.

The invention discloses a high-precision synchronous multi-channel image acquisition system and a method thereof. The system comprises a time source, a plurality of video acquisition units and a plurality of cameras. The method comprises six steps. According to the high-precision synchronous multi-channel image acquisition system and the method, synchronous time signal synchronization camera shooting is adopted for trigger signals, strict synchronization of shooting moments (exposure moments) of multi-channel cameras is achieved, the shooting moments are strictly synchronous with time of a time source, and the requirement for high-precision multi-channel synchronous image acquisition is met; timestamp information of trigger pulses is recorded, so that timestamps marked by images are the shooting moments, the timestamp marking precision is improved, follow-up information extraction and measurement analysis of multi-channel images are facilitated, and the good economic and social benefits are obtained.

Quality feedback in a streaming service wherein at least one media stream (101) is streamed to a client (601) and a quality feedback value is determined (304) according to at least one quality metric is improved by determining (305) a timestamp relating to said quality feedback value according to at least one timestamp metric, wherein for each of said at least one quality metrics, a corresponding timestamp metric is defined, and wherein each of said at least one timestamp metrics is based on a relative media playback time of said at least one media stream (101), and reporting (306) said quality feedback value and said related timestamp to a server (600). Said relative media playback time is preferably derived from RTP (102) timestamps, from a NPT provided by a RTSP (109), from timestamps of a RTCP or from timestamps of a SIP.

A detector (22) detects an event. First and second time-to-digital converters(TDCs) (70, 72) generate first and second time stamps (TS1, TS2) for the detection of the event. The first TDC and the second TDC are both synchronized with a common clock signal (62) that defines a fixed time offset between the second TDC and the first TDC. An autocalibration circuit (120) adjusts the first TDC and the second TDC to keep the time difference between the second time stamp and the first time stamp equal to the fixed time offset between the second TDC and the first TDC. The detector may be a detector array, and trigger circuitry (28) propagates a trigger signal from a triggering detector of the array of detectors to the first and second TDC's. Skew correction circuitry (132, 134, 136, 142, 60, 162) adjusts a timestamp (TS) based on which detector is the triggering detector.

A debugger inserts instrumentation hooks in a multi-threaded computer program that allow collecting a program trace and that provide timestamps that correspond to the program trace. When a breakpoint in a first thread is encountered, a timestamp corresponding to the breakpoint is retrieved. Execution of the other threads may continue until the debugger is able to halt their execution. Once the execution of all threads has been halted, the program trace for each thread is traced backwards to a point where the timestamp is less than the breakpoint timestamp. Instructions are then executed, one by one, until the execution time of the instructions plus the timestamp is approximately the same as the breakpoint timestamp. The instruction in the program trace display is then highlighted to indicate the instruction that was likely being executed when the breakpoint in the first thread is encountered.

The present invention provides a system and method of calculating a service disruption in a communication network comprising network elements, including nodes connected via links and at least one originating node. Each node is able to detect a failure in an adjacent network element. Upon detection of a failure, a first timestamp is generated. The detecting node generates a release signal which is transmitted, together with the first timestamp, to an originating node which releases the affected connection. The originating node establishes a new connection and initiates a new call. Upon establishing a new connection, a node affected by the failure, which forms a part of the new connection, records a second timestamp. The second timestamp is chosen to reflect, as closely as possible, the actual time of restoration of service in the network. Service disruption is measured as a difference between the first and second timestamps.

A method is disclosed for receiving a plurality of play events associated with a sporting event, wherein each play event of the plurality of play events comprises a timestamp; for each of the play events, associating the play event with a sports team of a plurality of sports teams; for each of the play events, associating with the play event a particular icon from among a plurality of different icons based, at least in part, on the sports team that is associated with the play event; causing to display a bar in a graphical user interface of a mobile computing device, wherein the bar represents at least a portion of a time duration of the sporting event; for each of the play events, causing to display the particular icon at a position in the bar, wherein the position is based, at least in part, on the timestamp of the event.

Methods and apparatus for synchronizing a first clock of a transmit node and a second clock of a receive node in a packet network are provided. Receive time stamps are generated for transferred packets at a receive node in-accordance with the second clock. Propagation delay variation is filtered from receive time stamp intervals through a filter in accordance with a frequency of the second clock. The filtered receive time stamp intervals and transmit time stamp intervals of the transferred packets are input into a phase locked loop to generate a new frequency for the second clock. The filter and the second clock are updated in accordance with the new frequency for synchronization with the first clock of the transfer node.

A communication network includes an SS7 Security Gatekeeper that authenticates and validates network control messages within, transiting, entering and leaving an overlying control fabric such as an SS7 network. The SS7 Security Gatekeeper incorporates several levels of checks to ensure that messages are properly authenticated, valid, and consistent with call progress and system status. In addition to message format, message content is checked to ensure that the originating node has the proper authority to send the message and to invoke the related functions. Predefined sets of templates may be used to check the messages, each set of templates being associated with respective originating point codes and/or calling party addresses. The templates may also be associated with various system states such that messages corresponding to a particular template cause a state transition along a particular edge to a next state node at which another set of templates are defined. Thus, system and call state is maintained. The monitor also includes signaling point authentication using digital signatures and timestamps. Timestamps are also used to initiate appropriate timeouts and so that old or improperly sequenced message may be ignored, corrected or otherwise processed appropriately. The SS7 Security Gatekeeper may be located at the edge of a network to be protected so that all messaging to and from the protected network most egress by way of the Gatekeeper. Alternatively, the SS7 Security Gatekeeper may be internal to the protected network and configured as a “pseudo switch” so that ISUP messaging is routed through the Gatekeeper while actual traffic is trunked directly between the associated SSPs, bypassing the Gatekeeper.