3255 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.

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.

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.

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.

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.