Abstract: A method and associated system for mitigating a Distributed Denial of Service (DDoS) attack on a target device including, receiving a plurality of data packets at a mitigation device, counting a number of occurrences of each destination address signature within each of a plurality of consecutive data packet windows, classifying each data packet window of the plurality of consecutive data packet windows as a potential attack window if the number of occurrences of any one destination address signature within the data packet window exceeds a destination address signature threshold value. The method further includes, determining a total number of potential attack windows within a sliding time window and limiting the transmission of the plurality of data packets from the mitigation device if a total number of potential attack windows within the sliding time window exceeds a potential attack window threshold value.

Abstract: Various electronic devices may benefit from appropriate power conservation techniques and tools. For example, low power techniques may benefit small form-factor pluggable applications. An apparatus can include a packet parsing functionality that includes a first order shallow packet parser configured to operate at line rate and a second order deep packet parser configured to operate only on received filtered packets and received packets destined for a management and/or central processing port. The apparatus can also include a microprocessor configured to manage the apparatus and configured to operate at a low duty cycle. The apparatus can further include a packet generator configured to be active only when generating certain packets of interest. The packet parsing function, the microprocessor, and the packet generator can be configured to provide data from a host port of a small form-factor pluggable device toward an optical port of the small form-factor pluggable device.

Abstract: With the increasing usage of mobile devices for communication, the need for wireless base-stations deployed in strategic locations is becoming increasingly important. The increased bandwidths being transmitted between the base-station and the mobile device has mandated that enhanced transmission formats and techniques be deployed, and, in order to operate correctly, these techniques require a tight synchronization in both time/phase, and in frequency, between the various base-stations serving a general area. Due to the need to establish the geographic location of the mobile device with a high degree of accuracy, it is also necessary to establish the location of the serving base-stations with a high degree of accuracy.

Abstract: Apparatuses and methods for sensing rotations are provided. One embodiment of the apparatus includes a cell containing alkali and active nuclear magnetic resonance (NMR) isotope(s) atoms, a magnet providing a first magnetic field, a light source, and optics which circularly polarize light to generate a pump beam for optically pumping the alkali atoms and, together with a second magnetic field orthogonal to the first magnetic field or a modulation of the light, causing the alkali and the NMR isotope atoms to precess about the first magnetic field. The apparatus further includes a partial reflector opposite the light source and configured to, in conjunction with a first linear polarizer, generate a reflected linearly-polarized probe beam from a portion of the pump beam, and one or more polarizing beam splitters configured to split light of the probe beam incident thereon into orthogonally polarized components that are detected and used to determine rotations.

Abstract: Various electronic devices may benefit from appropriate power conservation techniques and tools. For example, low power techniques may benefit small form-factor pluggable applications. An apparatus can include a packet parsing functionality that includes a first order shallow packet parser configured to operate at line rate and a second order deep packet parser configured to operate only on received filtered packets and received packets destined for a management and/or central processing port. The apparatus can also include a microprocessor configured to manage the apparatus and configured to operate at a low duty cycle. The apparatus can further include a packet generator configured to be active only when generating certain packets of interest. The packet parsing function, the microprocessor, and the packet generator can be configured to provide data from a host port of a small form-factor pluggable device toward an optical port of the small form-factor pluggable device.

Abstract: The present invention generally relates to methods and apparatus for precision time transfer wherein the inherent packet delay variation and possible asymmetry introduced in networks is avoided or mitigated. In one embodiment, the timing functions of a master device may be placed closer to a slave device using a Remote Time-Stamp Generator, located in the network between the master and the slave, and whose time reference serves as a proxy for the time reference of the master. Time-of-traversal of packets at the remote time-stamp generator may be used as proxies for the time-of-departure and the time-of-arrival of certain messages at the master. Such proxy times may be used to synchronize the slave with the master, particularly if the master and the Remote Time-Stamp Generator are both synchronized with a Global Navigation Satellite System (GNSS) source.

Abstract: With the increasing usage of mobile devices for communication, the need for wireless base-stations deployed in strategic locations is becoming increasingly important. The increased bandwidths being transmitted between the base-station and the mobile device has mandated that enhanced transmission formats and techniques be deployed, and, in order to operate correctly, these techniques require a tight synchronization in both time/phase, and in frequency, between the various base-stations serving a general area. Due to the need to establish the geographic location of the mobile device with a high degree of accuracy, it is also necessary to establish the location of the serving base-stations with a high degree of accuracy.

Abstract: The notion of a “PTP aware” path is one current proposed approach to reduce asymmetry effects. In a fully PTP aware path there is the notion of on-path support mechanisms such as boundary clocks and transparent clocks at every switching or routing node. However, on-path support methods only address time-transfer errors introduced inside network elements and any asymmetry in the transmission medium, such as, for example, the fiber strands for the two directions of transmission, cannot be compensated for by on-path support mechanisms. Furthermore, in a real operational network, which may traverse different operational domains administered by different entities, full on-path support is a difficult challenge. In certain managed network scenarios full on-path support can be contemplated. Nevertheless, the universal asymmetry compensation method described herein mitigates the asymmetry in a network path, without requiring on-path support mechanisms such as transparent clocks and boundary clocks.

Abstract: A method of providing forward error correction on an Ethernet point-to-point link, constituted of: receiving at one end of the point-to-point link an input data stream, wherein the input data stream is a 10 bit symbol encoded serial data stream at a first data rate; decoding the 10 bit encoded data stream to a 9 bit symbol data stream; increasing the data rate of the 9 bit symbol data stream to a second data rate; for each segment of a predetermined number of 9 bit symbols generating a respective plurality of parity symbols; combining the segments and the generated respective plurality of parity symbols into FEC appended segments; encoding the FEC appended segments into an output 10 bit symbol encoded data stream; and transmitting the output 10 bit encoded stream on the point-to-point link at the second data rate.

Abstract: The notion of a “PTP aware” path is one current proposed approach to reduce asymmetry effects. In a fully PTP aware path there is the notion of on-path support mechanisms such as boundary clocks and transparent clocks at every switching or routing node. However, on-path support methods only address time-transfer errors introduced inside network elements and any asymmetry in the transmission medium, such as, for example, the fiber strands for the two directions of transmission, cannot be compensated for by on-path support mechanisms. Furthermore, in a real operational network, which may traverse different operational domains administered by different entities, full on-path support is a difficult challenge. In certain managed network scenarios full on-path support can be contemplated. Nevertheless, the universal asymmetry compensation method described herein mitigates the asymmetry in a network path, without requiring on-path support mechanisms such as transparent clocks and boundary clocks.

Abstract: A clock at a first network element that is connected to a second network element over an optical fiber link is aligned in time/phase using packet protocols such as PTP. The invention discloses how to correct the asymmetry error inherent in traditional packet-based time-transfer methods.

Abstract: In one aspect, a method of determining a geographical location of a base station is provided. The base station is within a coverage area of a master base station and requests geographical location information from the master base station through a first Precision Time Protocol (PTP) management message. The base station receives the geographical location information from the master base station through a second PTP management message. In addition, the base station determines the geographical location of the base station from the geographical location information included in the second PTP management message.

Abstract: Apparatuses and methods for sensing rotations are provided. One embodiment of the apparatus includes a cell containing alkali and active nuclear magnetic resonance (NMR) isotope(s) atoms, a magnet providing a first magnetic field, a light source, and optics which circularly polarize light to generate a pump beam for optically pumping the alkali atoms and, together with a second magnetic field orthogonal to the first magnetic field or a modulation of the light, causing the alkali and the NMR isotope atoms to precess about the first magnetic field. The apparatus further includes a partial reflector opposite the light source and configured to, in conjunction with a first linear polarizer, generate a reflected linearly-polarized probe beam from a portion of the pump beam, and one or more polarizing beam splitters configured to split light of the probe beam incident thereon into orthogonally polarized components that are detected and used to determine rotations.

Abstract: The present invention generally relates to methods and apparatus for precision time transfer wherein the inherent packet delay variation and possible asymmetry introduced in networks is avoided or mitigated. In one embodiment, the timing functions of a master device may be placed closer to a slave device using a Remote Time-Stamp Generator, located in the network between the master and the slave, and whose time reference serves as a proxy for the time reference of the master. Time-of-traversal of packets at the remote time-stamp generator may be used as proxies for the time-of-departure and the time-of-arrival of certain messages at the master. Such proxy times may be used to synchronize the slave with the master, particularly if the master and the Remote Time-Stamp Generator are both synchronized with a Global Navigation Satellite System (GNSS) source.

Abstract: In one aspect, a method of determining a geographical location of a base station is provided. The base station is within a coverage area of a master base station and requests geographical location information from the master base station through a first Precision Time Protocol (PTP) management message. The base station receives the geographical location information from the master base station through a second PTP management message. In addition, the base station determines the geographical location of the base station from the geographical location information included in the second PTP management message.