A method for performing ONU Management and Control Interface (OMCI) synchronization includes receiving an OMCI message containing a OLT-G entity identifying OLT's vendor identification (ID) and version. The method also includes determining if an OLT vendor identification (ID) matches with a current vendor ID and if an Optical Line Terminal (OLT) version is compatible with current OMCI handlers. When the OLT vendor ID fails to match with the current vendor ID, automatically performing a OMCI handler switching process. The OMCI handler switching process includes setting a current OLT vendor as a new OLT vendor ID, deleting a OMCI configuration previously stored in the flash memory after setting the new OLT vendor ID, and rebooting the ONT to allow the ONT to initialize a OMCI configuration using a new OMCI profile.

Techniques for computer security, and more specifically timestamp-based key generation techniques, are described. Some implementations provide a table of key generation processes that is shared as a secret between a first computing system and a second computing system, both of which have synchronized clocks. Both computing systems use the same technique for selecting a key generation process from the table, such as based on a random number generator seeded with a timestamp. Since the computing systems have synchronized clocks, they both select and use the same key generation process, thereby generating the same encryption key without the need to communicate the key from one system to another. Furthermore, both computing systems may synchronize their clocks to a private time server that maintains a clock that runs faster or slower than standard time. Security is maintained by one or more of restricting access to the time server, using secret key generation processes, and/or using a secret random number generator.

A method for recovering the symbol time by a receiver to decode a sequence of symbols transmitted by a transmitter when the symbol time of the transmitter is biased with respect to the symbol time of the receiver. When a transition is detected between two consecutive symbols, an absolute error on the instant of the current symbol is measured and a statistical model of the bias is updated. A correction may then be applied to the instants of the subsequent symbols depending on the measured absolute error and/or a bias estimated from the statistical model. During periods in which there are no transitions between symbols, an absolute error cannot be measured, but it is still possible to apply a correction to the instants of the subsequent symbols depending on a relative error extrapolated from the statistical model.

A transport framework for heterogeneous data streams includes session management module and a connection management module. The session management module is configured to receive a request to establish a first stream that is used for transmitting or receiving data, where the request includes an express indication as to whether the first stream is reliable or unreliable; construct a first data frame based on application data; handoff the first data frame to the connection management module; and maintain a record for the first data frame that includes whether the first data frame is successfully transmitted to the receiver. The connection management module is configured to receive the first data frame of the first stream from the session management module; receive a second frame from the session management module; encapsulate the first data frame and the second frame in a packet; and transmit the packet to the receiver using an unreliable protocol.

Methods and devices for IQ time skew and conjugation compensation and calibration of a coherent transmitter or transceiver are described. A pilot tone is combined with a digital data signal such that relative powers of the pilot tone in each of two frequency bands of the transmitted data signal may be detected by a pilot tone detector and used to calculate the time skew between I and Q modulation channels of the transmitter. A transmitter DSP applies IQ time skew bias to the data signal to compensate for any calculated IQ time skew. The pilot tone detector also provides the transmitter DSP with the information necessary to detect phase conjugation of the optical signal, which can be corrected by inverting the polarity of the data signal or changing the phase bias point of the optical modulator.

A channel between quantum controller modules (e.g., pulse processors) is operable to communicate high speed data required for processing qubit states that may be distributed across a quantum computer. The latency of the communication channel is deterministic and controllable according to a system clock domain.

A clock generating circuit includes a first frequency multiplier configured to generate a second clock signal having a second frequency based on a first clock signal having a first frequency, and a second frequency multiplier configured to generate a third clock signal having a third frequency based on the second clock signal. The first frequency multiplier includes a circuit configured to control a duty cycle of the first clock signal, a delay circuit configured to receive the duty controlled clock signal, and delay the received signal based on a duty cycle of the second clock signal to output a first delay clock signal, and an XOR gate configured to perform an XOR computation using the duty controlled clock signal and the first delay clock signal to output the second clock signal. The second frequency is greater than the first frequency, and the third frequency is greater than the second frequency.

An apparatus for communication between a sending application and a receiving application of a receiving apparatus includes a processor that is configured to establish a stream for transmitting data between the sending application and the receiving application; receive a first request from the sending application to transmit metadata to the receiving application; receive a second request from the sending application to transmit application data to the receiving application; responsive to a determination that a frame that includes the application data and the metadata has a size that is smaller than or equal to a maximum frame size, construct the frame to include the application data and the metadata; and transmit the frame in a packet to the receiving apparatus.

The various implementations described herein include methods and systems for synchronous audio playback. In one aspect, a method is performed at each of a plurality of electronic devices, each having an audio system, an internal clock, processors and memory storing programs for execution by the processors. Each device is configured for two-way communications with a server and associated with a user account. The device receives an identification of a first device as a common clock device that has a first internal clock being designated as a master clock. The device receives a synchronized audio playback command that includes audio data to be output and a future playback time. In response to receiving the audio data, the device determines a synchronized audio playback time. If the determined synchronized audio playback time has not yet occurred, the electronic device outputs the audio data based on the determined synchronized audio playback time.

Method and system for managing the reception of data frames, scheduled statically and periodically, a frame includes a header provided with an identifier (id) of the frame and an index (index) representing the occurrence of the frame in a hyper-period.