Abstract: A software trusted platform module (sTPM) operates in a hypervisor, receives trust assurances from specialized hardware, and extends this trust such that the hypervisor performs trust attestation. The hypervisor receives a startup sequence validation from a TPM, or Trusted Platform Module. The TPM performs bus monitoring during a boot sequence of the computer system, records the startup sequence from the bus, and performs a hash on the sequence. The TPM performs an authentication exchange with the hypervisor such that the hypervisor authenticates the attestation of the computer system from the TPM, and the hypervisor, now delegated with trust assurances from the TPM, provides assurances to users via an authentication chain. The ATCB then performs the attestation of the computer system according to the attestation protocol much faster than the TPM. In this manner, the hypervisor operates as a software delegate of the TPM for providing user assurances of trust.

Abstract: A communications device with integrated case temperature measurement includes a case having at least one thermally conductive wall and a circuit board at least partially disposed within the case. At least one electronic component is mounted on the circuit board and a temperature sensor is mounted on the circuit board. At least one thermally conductive protrusion extends from the wall and is thermally coupled to the temperature sensor.

Abstract: A communications device with integrated case temperature measurement includes a case having at least one thermally conductive wall and a circuit board at least partially disposed within the case. At least one electronic component is mounted on the circuit board and a temperature sensor is mounted on the circuit board. At least one thermally conductive protrusion extends from the wall and is thermally coupled to the temperature sensor.

Abstract: A software trusted platform module (sTPM) operates in a hypervisor, receives trust assurances from specialized hardware, and extends this trust such that the hypervisor performs trust attestation. The hypervisor receives a startup sequence validation from a TPM, or Trusted Platform Module. The TPM performs bus monitoring during a boot sequence of the computer system, records the startup sequence from the bus, and performs a hash on the sequence. The TPM performs an authentication exchange with the hypervisor such that the hypervisor authenticates the attestation of the computer system from the TPM, and the hypervisor, now delegated with trust assurances from the TPM, provides assurances to users via an authentication chain. The ATCB then performs the attestation of the computer system according to the attestation protocol much faster than the TPM. In this manner, the hypervisor operates as a software delegate of the TPM for providing user assurances of trust.

Abstract: The case temperature measurement device for an optoelectronic transceiver includes a case with at least one thermally conductive wall, at least one optical component at least partially disposed within the case, circuitry electrically coupled to the optical component. The circuitry includes a temperature sensor coupled to the circuitry. The case temperature measurement device also includes at least one protrusion formed on the wall of the case of the optoelectronic transceiver. The protrusion is thermally coupled to temperature sensor via a thermal pad. A method for estimating case temperature of the optoelectronic transceiver based on an internal temperature measurement and knowledge of the relationship between the measured internal temperature and the actual case temperature, and compensating for the effects of variable heat sources within the transceiver upon this estimate.

Abstract: A temperature control system is provided for efficiently controlling the temperature of an optical transmitter such as a laser diode. The temperature control system of the present invention reduces power consumption and achieves a higher efficiency by employing a voltage controller and a high-efficiency DC-DC step-down converter between the TEC controller, which drives the thermoelectric cooler, and the microcontroller, which governs the optical transmitter operation. The voltage controller converts an analog voltage command signal into a current-based command signal, which is then sent to the DC-DC step-down converter. The DC-DC converter produces a stepped-down voltage which it supplies to the TEC controller. The TEC controller receives the stepped-down voltage input from the DC-DC converter and outputs a corresponding current signal to the thermoelectric cooler.

Abstract: The case temperature measurement device for an optoelectronic transceiver includes a case with at least one thermally conductive wall, at least one optical component at least partially disposed within the case, circuitry electrically coupled to the optical component. The circuitry includes a temperature sensor coupled to the circuitry. The case temperature measurement device also includes at least one protrusion formed on the wall of the case of the optoelectronic transceiver. The protrusion is thermally coupled to temperature sensor via a thermal pad. A method for estimating case temperature of the optoelectronic transceiver based on an internal temperature measurement and knowledge of the relationship between the measured internal temperature and the actual case temperature, and compensating for the effects of variable heat sources within the transceiver upon this estimate.

Abstract: A temperature control system is provided for efficiently controlling the temperature of an optical transmitter such as a laser diode. The temperature control system of the present invention reduces power consumption and achieves a higher efficiency by employing a voltage controller and a high-efficiency DC-DC step-down converter between the TEC controller, which drives the thermoelectric cooler, and the microcontroller, which governs the optical transmitter operation. The voltage controller converts an analog voltage command signal into a current-based command signal, which is then sent to the DC-DC step-down converter. The DC-DC converter produces a stepped-down voltage which it supplies to the TEC controller. The TEC controller receives the stepped-down voltage input from the DC-DC converter and outputs a corresponding current signal to the thermoelectric cooler.

Abstract: Techniques for controlling the operation of a laser diode to maintain optimum operating characteristics (i.e., fairly constant output power and extinction ratio) despite the fact that the threshold current and slope efficiency vary greatly over a the desired range of operating temperature. A laser driving circuit includes a bias current generator, a temperature-dependent modulation current generator, and a switching element for switching the modulation current on and off in accordance with a desired input pattern. The modulation current is caused to vary with temperature in a manner that compensates for the fact that the laser diode's slope efficiency varies with temperature.