Abstract: Disclosed are a time synchronization method and system. The method comprises: an NE1 and the upstream nodes of the NE1 are classified into the first level, and the downstream nodes of the NE1 are classified into the second level, where the first level priority of the first level is higher than the second level priority of the second level; an NE3 connected to the NE1 through a PTP synchronization link in the downstream node receives a first device priority of the NE1 and the first level priority from the NE1; and after the NE3 receives the second device priority of an NE2 and the second level priority sent by the NE2 in the downstream nodes which is connected to the NE1 through the 1PPS+TOD synchronization link, determines that a clock parameter of the NE1 is optimal, and synchronizes the local clock to the NE1.

Abstract: Provided are a synchronization track reference signal transmission processing, receiving processing method and apparatus. According to the transmission processing method, a base station configures, for a new carrier, subframe pattern information used for a synchronization track reference signal (STRS), wherein the subframe pattern information is used for describing at least one subframe for transmitting the STRS in a radio frame; and the base station transmits the configured subframe pattern information to user equipment. By applying the technical solution, the technical problems of being unable to transmit the STRS in a new carrier since there is not technical solution regarding how to transmit the STRS in the related technologies, etc. are solved, thereby achieving the transmission of the STRS in the new carrier.

Abstract: The present invention is designed to provide a communication system, a local area base station apparatus, a mobile terminal apparatus and a communication method that can provide highly efficient local area radio access. In a communication system in which a mobile terminal apparatus performs radio communication with a wide area base station apparatus that covers a wide area, using a first carrier frequency, and performs radio communication with a local area base station apparatus that covers a local area, using a second carrier frequency, the wide area base station apparatus allocates different frequencies between the uplink and the downlink in the first carrier frequency and communicates with the mobile terminal apparatus, and the local area base station apparatus dynamically switches between the uplink and the downlink in the second carrier frequency on a per time basis based on the communication environment, and communicates with the mobile terminal apparatus.

Abstract: Provided is a method and an apparatus for controlling inter-cellular interference in a heterogeneous network (HetNet) system, in which a macro cell and femto cells coexist. The apparatus for controlling inter-cellular interference overbears a control channel of the macro cell. The control apparatus determines an interference candidate resource, which is subject to inter-cell interference control, on the basis of the control channel. The control apparatus transmits an interference control message including information on the interference candidate resource.

Abstract: Technology for reducing signal interference is disclosed. Semi-static signaling can be received at a user equipment (UE) from a neighboring evolved node (eNB). The semi-static signaling can include potential configurations of signal parameters used at the neighboring eNB. The UE can receive dynamic signaling from the neighboring eNB that includes a subset of the potential configurations of signal parameters used at the neighboring eNB. Signal interference that is caused by the neighboring eNB can be reduced using the semi-static signaling and the dynamic signaling.

Abstract: A method for generating a virtual codebook of low peak to average power ratio (PAPR) sequences includes generating a plurality of low PAPR combination block sequences, with each low PAPR combination block sequence including at least one of a plurality of sparse codebook, and applying time domain hopping to the plurality of low PAPR combination block sequences, thereby producing a virtual codebook. The method also includes storing the virtual codebook.

Abstract: Methods and systems for a polarization immune wavelength division multiplexing demultiplexer are disclosed and may include, in an optoelectronic transceiver having an input coupler, a demultiplexer, and an amplitude scrambler: receiving input optical signals of different polarization via the input coupler, communicating the input optical signals to the amplitude scrambler via waveguides, configuring the average optical power in each of the waveguides utilizing the amplitude scrambler, and demultiplexing the optical signals utilizing the demultiplexer. The amplitude scrambler may include phase modulators and a coupling section. The phase modulators may include sections of P-N junctions in the two waveguides. The demultiplexer may include a Mach-Zehnder Interferometer. The demultiplexed signals may be received utilizing photodetectors. The input coupler may include a polarization splitting grating coupler.

Abstract: An optical transmission apparatus includes: a variable optical attenuation section configured to independently adjust, for each wavelength, attenuation of light of a plurality of wavelengths and adjust output optical power of wavelength multiplexed light that is output to an optical transmission line by adjustment of the attenuation; and a control section configured to stop, in accordance with control in which a wavelength included in the wavelength multiplexed light in a first wavelength band is wavelength-shifted to a second wavelength band that is different from the first wavelength band, adjustment of attenuation performed on the first wavelength band by the variable optical attenuation section.

Abstract: A method includes profiling user-network interface (UNI) ports including Optical channel Data Unit flex (ODUflex) in a network; and adapting, using a max-flow routing criterion, network-network interface (NNI) ports comprising ODUflex based on the profiling. A network includes a plurality of network elements; a plurality of links interconnecting the plurality of network elements, wherein the plurality of links includes Layer 0 Dense Wave Division Multiplexing (DWDM) bandwidth and Layer 1 Optical Transport Network (OTN) bandwidth; and a control plane operating between the plurality of network elements; wherein the Layer 0 DWDM bandwidth and the Layer 1 OTN bandwidth is statistically multiplexed using the control plane and manager based on monitoring bandwidth usage thereon over time.

Abstract: An optical line terminal (OLT) coupled to a plurality of optical network units (ONUs) through a passive optical network (PON). The OLT includes a transceiver configured to communicate via a management channel of a communication network with a plurality of OLTs. The communication includes sending or receiving a notification, wherein the notification includes the following: a source OLT identifier associated with a source OLT sending the notification, wherein the source OLT is configured to communicate over a first channel at a first wavelength of the PON; a destination OLT identifier associated with a destination OLT receiving the notification, wherein the destination OLT is configured to communicate over a second channel at a second wavelength of the PON; and an ONU identifier associated with a first ONU associated with the notification.

Abstract: A method, device, and system for secure end-to-end audio recognition is disclosed. A client device launches an application that connects with a server. The client device and server exchange cryptographic keys and establish a secure connection and a shared cryptographic key. The server transmits an encrypted audio prompt to the client device. The client device decrypts the encrypted audio prompt and stores the decrypted audio prompt in secure memory inaccessible to the operating system using an audio engine of the client device. The audio engine then retrieves the audio and renders it for the user through the speakers of the client device. The client device captures the user's audio response with a microphone and stores the audio response in the secure memory. The stored audio response is encrypted and transmitted to the server.

Abstract: Provided are processes for suppressing jamming signals that may include use of a signal processing circuit. A signal processing circuit can be configured to obtain a jamming signal and a feedback signal, process the jamming signal and the feedback signal to determine a cancellation signal for use in suppressing the jamming signal, and output the cancellation signal to a radio-frequency transmitter. The signal processing circuit may be further configured to obtain a transmission signal, determine a jamming channel from the jamming signal and a feedback channel from the feedback signal, and combine the transmission channel, jamming channel, and feedback channel to determine a transfer function, where the transfer function is configured to determine the cancellation signal.

Abstract: A transmitter may be operable to generate a sequence of symbols which may comprise information symbols and one or more pilot symbols. The transmitter may transmit the information symbols at a first power and transmit the one or more pilot symbols at a second power. In instances when a particular performance indicator is below a determined threshold, the first power may be set to a first value and the second power may be set to zero value. In instances when the particular performance indicator is above the determined threshold, the first power may be set to a second value and the second power may be set to a non-zero value. A value of the first power and a value of the second power may be based on an applicable average power limit determined by a communications standard with which the transmitter is to comply.

Abstract: A communication technique for energy efficient Ethernet (EEE) employs a systematic block forward error correcting code (FEC). The technique aligns a low power idle (LPI) refresh signal with the FEC frame. The refresh signal includes a known reference sequence, FEC systematic symbols, and FEC parity symbols. The technique may apply shortened FEC encoding and decoding on the partial data symbols and the parity symbols.

Abstract: A 4B5B encoder converts an inputted 4-bit data into a pattern of a 5-bit data in which (i) the number of bits of consecutive “0” data values is permitted to be maximum two, and, simultaneously, (ii) maximum one bit of head end two bits is permitted to have a “0” data value and maximum one bit of tail end two bits is permitted to have a “0” data value. A 5N-bit command encoder converts a command into a command pattern in which the number of bits contained in consecutive “0” data values is permitted to be maximum two. The data after the conversion and the command after the conversion are converted into NRZI codes by an NRZI encoder.

Abstract: A receiving circuit for a digital television is provided. The receiving circuit of the digital television, adapted to process a digital television signal to generate transmission data, includes: a front-end circuit, configured to process the digital television signal to generate an interleaved signal; a setting unit, configured to provide a setting value associated with a digital video standard of the digital television signal; a frequency de-interleaving and time de-interleaving circuit, configured to select a frequency de-interleaving scheme and a time de-interleaving scheme corresponding to different digital video standards according to the setting value, and to process the interleaved signal to generate a de-interleaved signal; a quadrature amplitude modulation (QAM) demapping circuit, configured to demap the de-interleaved signal to generate a demapped signal; and a decoder, configured to decode the demapped signal to generate the transmission data.

Abstract: A bit interleaver, a bit-interleaved coded modulation (BICM) device and a bit interleaving method are disclosed herein. The bit interleaver includes a first memory, a processor, and a second memory. The first memory stores a low-density parity check (LDPC) codeword having a length of 64800 and a code rate of 4/15. The processor generates an interleaved codeword by interleaving the LDPC codeword on a bit group basis. The size of the bit group corresponds to a parallel factor of the LDPC codeword. The second memory provides the interleaved codeword to a modulator for quadrature phase shift keying (QPSK) modulation.

Abstract: Methods and apparatus for implementing notification by network elements of packet drops. In response to determining a packet is to be dropped, a network element such as a switch or router determines the source of the packet and returns a dropped packet notification message to the source. Upon receipt of notification, networking software or embedded hardware on the source causes the dropped packet to be retransmitted. The notification may also be sent from the network element to the destination computer to inform networking software or embedded logic implemented by the destination computer that the packet was dropped and notification to the source has been sent, thus alleviating the destination from needing to send a Selective ACKnowledge (SACK) message to inform the source the packet was not delivered.

Abstract: A method for allocating resources in a mobile communication system is provided. The resource allocation method includes determining whether a transmission time of response information indicating presence/absence of an error in received data overlaps a transmission time of channel state information; and when the transmission times overlap each other, allocating, to the response information, a resource block for the channel state information, cyclic shift values in a frequency domain, and orthogonal sequences having orthogonality in a time domain.

Abstract: Soft buffer management circuitry is provided for use in a device of a wireless communication system. The soft buffer management circuitry has input circuitry for receiving information relating to an aggregated carrier comprising a plurality, NDU/ULcells, of configured component carriers. Control circuitry is provided for prioritizing allocation of storage in the soft buffer depending on a carrier index value indicating a prioritization of a corresponding component carrier relative to the other configured component carriers. The buffer is partitioned into a number min (NC, NDL/ULcells) partitions, where NC gives a number of carriers for which soft buffer storage is to be prioritized. A UE comprising the soft buffer management circuitry and a soft buffer management method are also provided.

Abstract: An electro-optic device includes: an electro-optic panel displaying a display image with illumination light emitted from an illumination device; a display control circuit controlling the electro-optic panel to display a right-eye image during a right display period and display a left-eye image during a left display period; a glasses control circuit controlling a right-eye shutter of stereoscopic vision glasses so as to maintain an open state during the right display period, controlling a left-eye shutter of stereoscopic vision glasses so as to maintain an open state during the left display period, and controlling both the right-eye shutter and the left-eye shutter so as to maintain a close state during a blocking period; and an illumination control circuit controlling the illumination device to vary an intensity of the illumination light in a pulsed shape during the blocking period.

Abstract: Disclosed and recited herein are devices, systems, methods, and programs by which data is transmitted and, when receipt of the transmitted data has not been acknowledged, an impulse noise occurrence may be diagnosed at the transmitter based on flag streams associated with data transfer units corresponding to the transmitted data. Characteristics of the impulse noise occurrence may be diagnosed based on, at least, a number of consecutive error bits in at least one of the flag streams associated with the data transfer units corresponding to the transmitted data.

Abstract: According to one embodiment of the invention, a non-transitory computer readable medium for configuring a noise floor of a network device based on the detection of a non-Wi-Fi signal is described. One embodiment of the non-transitory computer readable medium comprises instructions that detect a non-Wi-Fi signal, determine a noise floor based on at least one attribute of the non-Wi-Fi signal and configure the noise floor of the network device such that the network device receives signals with a signal strength above the noise floor value.

Abstract: In a cable network, embodiments detect and remediate a non-responsive customer premise equipment (CPE) device in a customer's premise with minimal or no interaction with a customer. Embodiments may detect and remediate a non-responsive CPE device without rebooting the non-responsive CPE device or the associated cable modem. Embodiments include troubleshooting a data link layer (e.g., Open System Interconnection (OSI) layer 2, or media access control (MAC) layer) and a network layer (e.g., OSI layer 3, or Internet layer) between a service operator network and the non-responsive CPE device. Embodiments include a guided integration and a proactive integration method, computer program product, and system to reduce and/or eliminate the need for a customer service representative to reboot a cable modem, and/or for a customer to reboot a non-responsive CPE device resulting in a fast and less disruptive service experience for the customer.

Abstract: Filterbank windowing and Fourier transformation are used to distinguish sub-bands of interest from other sub-bands of an input signal. The sub-bands of interest are selected and then subjected to additional windowing and Fourier transformation.

Abstract: Wireless device, computer readable medium, and methods for signaling a resource allocation in a high-efficiency (HE) signal field are disclosed. A HE wireless local area network (HEW) device may include circuitry configured to: generate a HE signal (HE-SIG) field comprising one or more resource allocations each comprising an identical allocation subfield, an allocation or no allocation subfield, if the identical allocation subfield indicates the resource allocation is not identical, an allocation size if the identical allocation subfield indicates the resource allocation is not identical, and a station identification (ID), if the allocation or no allocation subfield indicates there is an allocation. The circuitry is further configured to transmit the HE-SIG field to one or more HEW stations. The allocation size may be based on a number of basic allocation units. The resource allocations may be allocated from a left side of a bandwidth to a right side of a bandwidth.

Abstract: A method for a terminal to receive a signal in a wireless communication system according to one embodiment of the present invention comprises a step for confirming whether a configuration change exists for a cell-specific reference signal (CRS) of a neighboring cell, and if the CRS configuration is changed for a neighboring cell, the method for receiving s signal comprises the steps of: receiving system information of the neighboring cell and acknowledging the changed CRS configuration thereby; and receiving s signal from a serving cell by means of the changed CRS configuration of the neighboring cell.

Abstract: A method and apparatus are provided for transmitting uplink signals including feedback for use in scheduling at different evolved Node Bs (eNBs) without intermodulation interference, especially in cases where the User Equipment (UE) is connected to an inter-duplex inter-eNB system in which the cooperation between eNBs is very slow or non-existent.

Abstract: It is presented a method for obtaining a capability of channel spacing between component carriers used in carrier aggregation for a user equipment, UE. The method is performed in a network node and comprises the step of: determining, from a plurality of alternatives, the capability of channel spacing for the UE based on signalling between the UE and the network node, the channel spacing capability comprising at least one of the alternatives of: a multiple of 300 kHz, a multiple of 15 kHz and any other channel spacing. A corresponding network node and UE are also presented.

Abstract: Techniques are disclosed for ACK/NAK bit bundling in carrier aggregation scenarios. Such measures exemplarily comprise generating a set of acknowledgement bits confirming receipt of payload data of a radio frame in a carrier aggregation mode aggregating a primary and at least one secondary carrier, said radio frame being divided into a plurality of downlink subframes and uplink subframes, each of said downlink subframes comprising at least one codeword per carrier, each of said acknowledgement bits is allocated to one of said codewords of one of said downlink subframes, and applying spatial domain bundling and/or time domain bundling on said set of acknowledgement bits distinctive for each of said primary and said at least one secondary carrier, wherein said spatial domain bundling is an AND operation of all acknowledgement bits allocated to each codeword of one carrier of said primary and said at least one secondary carrier and one downlink subframe.

Abstract: A dual band spectrum allocation system and method for wireless data communications uses discrete bands for upstream and downstream data communications. A preferred embodiment uses unlicensed UNII bands for license-free data transmissions from a subscriber to a hub, and uses relatively interference free licensed bands for data transmissions from a hub to subscribers, thereby allowing use of greater bandwidth, simplifying system licensing and reducing filtering requirements for subscribers.

Abstract: The present invention relates to a wireless communication system. More particularly, the present invention relates to a method and to an apparatus for transmitting an SRS in a multi-antenna system. The method comprises the steps of: acquiring specific information for discriminating a first antenna group and a second antenna group from among a plurality of antennas, wherein said first antenna group includes one or more antennas which are set to a turned-on state to perform communication with a base station, and said second antenna group includes one or more other antennas which are set to a turned-off state; transmitting an SRS to the base station if a predetermined condition is satisfied, under the condition that the second antenna group is set to the turned-off state; and setting the second antenna group to a turned-off state after the transmission of the SRS.

Abstract: A method and apparatus for transmitting a downlink reference signal in a wireless communication system supporting multiple antennas are discussed. A method for transmitting Channel State Information-Reference Signals (CSI-RSs) for eight or less antenna ports includes selecting one of a plurality of CSI-RS Resource Element (RE) groups defined on a data region of a downlink subframe and mapping CSI-RSs for the eight or less antenna ports to the selected CSI-RS RE group, and transmitting the downlink subframe in which the CSI-RSs for the eight or less antenna ports are mapped.

Abstract: A controlling base station sends, to a wireless communication device, control data related to communication between a communication base station and the wireless communication device. The control data is transmitted in accordance with a communication specification and is transmitted to allow reception by the wireless communication device of the control data within a data channel having a frequency and time allocated by the communication specification for the wireless communication device to receive data transmissions from the communication base station.

Abstract: The present invention relates to a wireless communication system. More particularly, the present invention relates to a method for performing processes in which a terminal determines control channel allocation, as well as to an apparatus for the method. The method comprises the following steps: monitoring, on a first carrier, a first search space, containing a control channel candidate set, for control channels having no carrier indication information; and monitoring, on a second carrier, a second search space, containing a control channel candidate set, for control channels having carrier indication information. If the terminal is set to monitor a plurality of control channel candidates which have the same radio network temporary identifier (RNTI), the same information size, and the same first control channel element (CCE) in the first search space and in the second search space, the control channels are received only in the first search space on the first carrier.

Abstract: A method for transmitting ACK/NACK (Acknowledge/Negative ACK) information at a user equipment in a wireless communication system, and a user equipment therefore are discussed. The method according to one embodiment includes generating an ACK/NACK payload for a plurality of carriers, the ACK/NACK payload including a plurality of concatenated ACK/NACK sets. Each ACK/NACK set is associated with a respective one of the plurality of carriers and has one or more ACK/NACK bits. The method further includes transmitting the ACK/NACK payload through a PUCCH (Physical Uplink Control Channel) or PUSCH (Physical Uplink Shared Channel). The ACK/NACK payload includes an ACK/NACK bit for a semi-persistent scheduled downlink signal. The ACK/NACK bit for the semi-persistent scheduled downlink signal is positioned at an end of a corresponding ACK/NACK set, not an end of the ACK/NACK payload.

Abstract: A method for transmitting, by a user equipment, uplink control information, and a user equipment therefore are discussed. The method according to one embodiment includes determining respective first acknowledgement, negative acknowledgement or discontinuous transmission (ACK/NACK/DTX) responses for four downlink (DL) subframes of a first carrier and respective second ACK/NACK/DTX responses for four DL subframes of a second carrier; and transmitting ACK/NACK information representing the first and second ACK/NACK/DTX responses through the first or second carrier in an uplink (UL) subframe. For a same sequence of the first ACK/NACK/DTX responses for the four DL subframes of the first carrier, a same ACK/NACK information is transmitted when a sequence of the second ACK/NACK/DTX responses for the DL subframes of the second carrier is ‘ACK, ACK, ACK, ACK’ and when the sequence of the second ACK/NACK/DTX responses for the DL subframes of the second carrier is ‘ACK, DTX, DTX, DTX’.

Abstract: Systems, methods, and devices for high-efficiency wireless frequency division multiplexing are provided. A method includes determining, at an access point, a performance characteristic for each wireless device in a set of wireless devices associated with the access point. The method further includes categorizing each wireless device in the set into at least a first and second subset of wireless devices based on the performance characteristic. The method further includes receiving communications from the first subset of wireless devices on a first set of wireless frequencies. The method further includes receiving communications from the second subset of wireless devices on a second set of wireless frequencies, the second set of wireless frequencies being a subset of the first. The first set of wireless devices have a higher performance characteristic than the second set of wireless devices.

Abstract: According to one embodiment of the present invention, there is provided a method for aggregating a plurality of cells. According to the method, a first cell may determine whether to add one or a plurality of second cells for user equipment. Here, a maximum number of cells are determined depending on a number of cells that belong to the first cell and the one or the plurality of second cells and whose reference configuration has been set as a specific Time Division Duplex (TDD) UL-DL configuration and a number of cells that have been actually set as the specific TDD UL-DL configuration. Also, the first cell may transmit a configuration for adding one or a plurality of second cells to the user equipment based on the determined maximum number of cells.

Abstract: A system of operating a wireless device in a wireless communication network includes selecting, by the wireless device, a preferred operating mode for use by the wireless device, the selection being made from at least a full duplex operating mode in which the wireless device can transmit and receive simultaneously on the same frequency band and a non full duplex operating mode; and transmitting a signal indicating the selected preferred operating mode to a network entity.

Abstract: A method and apparatus for allocating resources in a base station (BS) in a carrier aggregation (CA) system is provided. The method and apparatus includes configuring a first cell and a second cell for a first user equipment (UE), identifying at least one second subframes of the first cell, the at least one second subframe being associated with feedback information to be received in a first subframe of the first cell, and at least one third subframes of the second cell, determining whether there is a downlink (DL) data transmission in the at least one third subframe of the second cell, and determining to allocate the other frequency resources, which are other than a frequency resource used for transmission of the feedback information in the first subframe, to a second UE, if there is no DL data transmission in the at least one third subframe of the second cell.

Abstract: A communications system receiver is described providing automatic timing adjustment of receive data sampling. A concurrently received clock signal is used as both a reference for generation of internal receiver timing signals, and as an exemplar for adjustment of those timing signals to optimize received data sample timing.

Abstract: This disclosure provides a clock recovery circuit for a multi-lane communication system. Local clocks are recovered from the input signals using respective local CDR circuits, and associated CDR error signals are aggregated or otherwise combined. A global recovered clock for shared use by the local CDR circuits is generated at a controllable oscillation frequency as a function of a combination of the error signals from the plurality of receivers. A voltage- or current-controlled delay line can also be used to phase adjust the global recovered clock to mitigate band-limited, lane-correlated, high frequency jitter.

Abstract: A method for providing network time synchronization using a redundant grandmaster includes sensing a loss of the grandmaster. A sync message is generated according to a sensed result. The generated sync message is transmitted through a clock master port.

Abstract: An electronic system, comprising a first semiconductor device, a second semiconductor device, a clock circuit, and a plurality of independently adjustable calibration circuits connected in each of the plurality of serial data paths. The first semiconductor device may comprise a plurality of Serializer-Deserializer interfaces. The second semiconductor device may comprise a plurality of serial data interfaces coupled to the plurality of Serializer-Deserializer interfaces to provide a plurality of serial data paths between the first semiconductor device and the second semiconductor device. The plurality of Serializer-Deserializer interfaces and the plurality of serial data interfaces may be clocked from a clock signal derived from the clock circuit. The plurality of independently adjustable calibration circuits may be configured to compensate for timing differences across the plurality of serial data paths.

Abstract: A communication device includes a reception buffer configured to receive a pulse signal cyclically transmitted from a transmission source device via a transmission line; a branch circuit configured to generate a branch pulse signal by branching the pulse signal; a delay circuit configured to add a predetermined delay time to the generated branch pulse signal; and a transmission buffer configured to transmit the branch pulse signal to which the predetermined delay time was added to the transmission source device via the transmission line.

Abstract: An elastic gear First-In-First-Out (FIFO) buffer architecture is disclosed. The proposed elastic gear FIFO buffer uses a frequency monitor unit to control clock frequency compensation. By using an independent frequency monitor unit, the data latency and FIFO buffer size are best optimized. An elastic gear FIFO could be utilized in applications where clock compensation and asynchronous data width conversion are desired or required.

Abstract: Disclosed is a function masking apparatus in a symmetric cryptographic algorithm for preventing side channel attacks, including: a controller creating lookup tables for one or more internal functions included in a high security and light weight (HIGHT) algorithm, respectively based on a plurality of non-linear functions, a plurality of linear functions, and a plurality of constants which are randomly generated; and a storage unit storing the lookup tables for one or more internal functions included in the generated HIGHT algorithm.

Abstract: Methods and systems are provided for securely authenticating data of an integrated circuit. By authenticating data having keystream blocks inserted between ciphertext portions, it becomes more difficult to mount successful authentication-based attacks.

Abstract: In representative embodiments, a rule-based certificate cryptographic key material comprising containing a rule set defining validity conditions is associated with cryptographic key material assigned to an entity for use in authenticated communications. The validity of the cryptographic material changes state based on whether the entity is compliant or non-compliant with the rule set. This is accomplished in a representative embodiment by suspending the validity of the cryptographic key material when the entity is non-compliant with the rules and reinstating the validity of the cryptographic key material when the entity becomes compliant. A rules compliance service determines the validity of the cryptographic material in part using updates sent by the entity. Entities can delegate the update to a delegate device. Encryption can be used to preserve privacy.