摘要:
In one implementation, computer executable instructions are provided to identify a group of instructions corresponding to a code block for an executable module. The instructions increment a counter associated with the code block to indicate the code block has been tested.
摘要:
An iterative method is provided for progressively building an end-to-end entanglement between qubits in first and second end nodes (91, 92) of a chain of nodes whose intermediate nodes (90) are quantum repeaters. At each iteration, a current operative repeater (90) of the chain merges an entanglement existing between qubits in the first end node (91) and the operative repeater, with a local entanglement formed between qubits in the operative repeater and its neighbour node towards the second end node (92). For the first iteration, the operative repeater is the neighbour of the first end node (91); thereafter, for each new iteration the operative repeater shifts one node further along the chain toward the second end node (92). A quantum repeater adapted for implementing this method is also provided.
摘要:
In order to facilitate alignment of a QKD transmitter and QKD receiver, the transmitter is provided with a retro-reflector for returning to the receiver a photon beam originating at the latter. The transmitter is arranged to polarization modulate the retro-reflected beam. The transmitter is provided both with an intensity detector for generating an indication of retro-reflected photon intensity, and an intensity-dependent controller for controlling the QKD transmitter in dependence on the detected photon intensity. In one embodiment, this control involves aborting operation of the QKD transmitter upon an unexpectedly high photon intensity being detected; in another embodiment, the intensity indication is used to control the attenuation of the retro-reflected beam so as stabilize the average retro-reflected photon count per unit time.
摘要:
A method includes executing a hypervisor (165) with computing hardware (105) to implement a virtual machine (175); responsive to detecting a removable storage medium (115) communicatively coupled to the computing hardware (105), executing a virtualized migration control appliance (180) through the hypervisor (165) separate from the virtual machine (175); and blocking the virtual machine (175) from accessing data (185) stored by the removable storage medium (115) with the virtualized migration control appliance (180) if at least one governing policy prohibits the virtual machine (175) from accessing the data (185).
摘要:
A method for conducting a privacy ensured computerized poll includes, in a computerized anonymizing system (100), receiving a list (404) of invited participants (418) of said computerized poll, said list (404) comprising at least one address (202, 204) for each said participant (418). With said computerized anonymizing system (100), assigning each invited participant (418) in said poll at least one character string (410, 412) and transmitting to each invited participant (418) said at least one character string (410, 412) assigned to said participant (418) using said at least one address (202, 204). With said computerized anonymizing system (100), generating a list (408) comprising an entry for each said at least one character string (410, 412) assigned to one of said invited participants (418) and shuffling an order of said entries, and providing said shuffled list (408) to a poll initiator (402).
摘要:
Various method and system embodiments of the present invention are directed to executing bit-commitment protocols. In one embodiment of the present invention, a method for executing a bit-commitment protocol for transmitting a bit from a first party to a second party comprises preparing a three qubits are entangled in a W-state, and storing a first of the three qubits in a first storage device controlled by the first party, a second of the three qubits is stored in a second storage device controlled by the second party, and a third of the three qubits is stored in a third storage device controlled by a third party. The bit is revealed to the second party by transmitting the first and third qubits to the second party and measuring the states of the three qubits to which of the entangled W-states the three qubits are in.
摘要:
In order to facilitate alignment of a QKD transmitter and QKD receiver, the transmitter is provided with a retro-reflector for returning to the receiver a photon beam originating at the latter. The transmitter is arranged to polarization modulate the retro-reflected beam. The transmitter is provided both with an intensity detector for generating an indication of retro-reflected photon intensity, and an intensity-dependent controller for controlling the QKD transmitter in dependence on the detected photon intensity. In one embodiment, this control involves aborting operation of the QKD transmitter upon an unexpectedly high photon intensity being detected; in another embodiment, the intensity indication is used to control the attenuation of the retro-reflected beam so as stabilize the average retro-reflected photon count per unit time.
摘要:
Secret random data is distributed to a plurality of devices to provision them with new one-time pad data for use in interacting with apparatus holding the same one-time pad data. This distribution is effected by provisioning a first device with a block of secret random data that is, or will become, available to the apparatus. Part of the secret random data is then distributed from the first device to one or more other devices in a hierarchical distribution pattern headed by the first device. Each device, other than those at the bottom of the distribution hierarchy, retains part of the secret random data it receives and passes on the remainder. Each device uses that part of the secret random data it has retained to provide the device with new one-time pad data. A method is also provided for tracking service usage based on the. distributed one-time pad data.
摘要:
A quantum key distribution (QKD) system is provided that makes use of a quantum signal of polarized photons and comprises a QKD device and complimentary QKD apparatus. The QKD device has a QKD subsystem comprising one of a QKD transmitter and receiver for inter-working with a complimentary QKD receiver or transmitter of said apparatus. The device also has an alignment subsystem arranged to wirelessly interact with the QKD apparatus to enable generation of user feedback and/or adjustment signals for use in aligning the QKD transmitter and receiver such that the QKD transmitter is pointing at the QKD receiver and the polarization axes of the QKD transmitter and receiver are aligned.
摘要:
An iterative method is provided for progressively building an end-to-end entanglement between qubits in first and second end nodes (91, 92) of a chain of nodes whose intermediate nodes (90) are quantum repeaters. At each iteration, a current operative repeater (90) of the chain merges an entanglement existing between qubits in the first end node (91) and the operative repeater, with a local entanglement formed between qubits in the operative repeater and its neighbor node towards the second end node (92). For the first iteration, the operative repeater is the neighbor of the first end node (91); thereafter, for each new iteration the operative repeater shifts one node further along the chain toward the second end node (92). A quantum repeater adapted for implementing this method is also provided.