Abstract: In a wireless packet switching telecommunications network, voice services are provided by having a compressor/decompressor in each mobile station to provide each voice packet with a compressed header. Voice data and signalling data are sent separately and in different data formats to the air interface. The compressed header may be an M bit and a cyclically reset timeclick_number, which is decompressed by use of a wallclock which counts reset cycles to reinstate the voice packet headers. Alternatively, RTP agents are provided at the compression and decompression points, and voice packets are sent without headers over a “high quality” network such as a frame relay or ATM network. Compression state of a voice packet header can be established by sending call setup information over an out-of-band channel between compression points in a mobile station and in the network.

Abstract: Linux's NAT (Network Address Translator) implementation, IP Masquerade, includes a VPN Masquerade feature that provides interoperation of NAT with IKE and ESP tunnel mode within the IPSec security protocol suite. VPN Masquerade uses heuristics to route packets from a server on the Internet to a client on a local network that shares access to the Internet with other clients over a common access link through a router running NAT. VPN Masquerade, however, is susceptible to crashes, collisions and race conditions that can disable IPSec communication. These are prevented, or recovery from such is automatically effected, by sending over a tunnel a control packet, a “ping”, from the client at one end of the tunnel to the server at the other end of the tunnel, and then waiting to send any packets other than a control packet over the tunnel until a responsive control packet is received from the server.

Abstract: An apparatus in one example comprises a management component that handles information storage to one or more storage locations of a database. The one or more storage locations comprise one or more available locations that are free of allocation to any particular variable. The management component maps one or more variables of one or more client applications to respective one or more selected locations of the one or more available locations.

Abstract: The probability of a time out and the resulting waste of channel capacity in a communication system is decreased by controlling the length of the time out period so as to minimize the number of time outs that occur. The length of the time out is based on the sum of the average channel delay and four times the deviation in the channel delay. A delay is introduced into the communication channel so as to increase the deviation in the channel delay. This results in an increase in the length of time required for a time out. As a result, the number of time outs is drastically decreased which in turn decreases the number of wasteful ramp up times that results in a more efficient use of channel capacity.

Abstract: A driver, e.g., for use with electro-optic (E/O) modulators. The driver is configured to generate a driving signal based on an electronic NRZ input data signal and an input clock signal. The driver converts the NRZ input data signal to an RZ format and produces an amplified RZ signal that can be applied to an E/O modulator. The amplification gain of the driver is adjustable to enable interfacing with different modulators. In one embodiment of the invention, the driving signal is generated based on a comparison between the NRZ input data signal and an offset clock signal generated from the input clock signal. The width of pulses in the driving signal, e.g., corresponding to logical “ones,” may be tuned by, e.g., changing the DC offset of the clock signal. The driver may be implemented as an ASIC configured to operate at the data rate of, e.g., 10 GBit/s.

Abstract: Method and apparatus for fault localization in an optical network using time trend correlation of end node performance parameters and intermediate node performance parameters, such as QoS and quasi-Q factors, respectively. The method and apparatus are bit-rate and protocol independent, enabling testing for each channel of a diverse dense wavelength division multiplexed traffic system using a single set of hardware.

Abstract: An optical device having a semiconductor optical amplifier (SOA) coupled to an optical filter, which device may be used for optical performance monitoring. One embodiment of the invention provides an optical regenerator/monitor (RM), in which an SOA is used both for optical regeneration of a communication signal applied to the RM and for evaluation of the quality of that signal. The RM has (i) a 2R regenerator, which includes the SOA and an optical filter, and (ii) a relatively simple signal processor configured to receive optical signals from two or more sampling points located at the regenerator. In one configuration, the processor evaluates the quality of the communication signal by comparing optical power tapped from the input and output of the regenerator. The RM, so configured, can be used, for example, to monitor chromatic dispersion and/or optical noise in the communication signal.

Abstract: The per antenna capacity of each of the transmitter antennas in a MIMO system are individually determined from measurable information at the receiver end. Specifically, the channel capacity for each individual transmitter antenna is calculated at the receiver end as a function of measurable channel coefficients (also known as channel state information), the measurable average signal-to-noise ratio, and the number of transmitter antennas. Once the per antenna capacity of each transmitter antenna is individually determined at the receiver end, the maximum transmission rate for each data stream transmitted by each transmitter antenna is determined from that individual capacity either at the receiver end and fed back to the transmitter end, or is determined at the transmitter end from the individual transmitter antenna capacities that are fed back by the receiver end to the transmitter end. A modulation scheme that supports each maximum transmission rate is then determined based on some defined criteria.

Abstract: In the method, a detector retrieves certain signal samples from a data frame that are accumulated in a buffer of a base station receiver. The detector generates a first metric representing a first signal sample and a second metric representing a second signal sample, and calculates a sum of the first and second metrics and a difference between the first and second metrics. A calculator uses the sum to calculate at least one threshold value, and a comparator compares the difference to the calculated threshold value to determine an on-time error for the frame. Based on the determined on-time error, an adjuster adjusts timing for the on-time error, and feeds back an on-time error correction to the buffer for subsequently received data frames.

Abstract: A monolithic waveguide/MEMS switch is disclosed that has a waveguide portion and a MEMS mirror portion fabricated on a single substrate, such as a as a silicon-on-insulator wafer. The monolithic waveguide/MEMS switch adjusts the phase of an optical signal by varying the position of one or more moveable mirrors. The mirror portion includes a mirror having a reflective surface that is attached to at least one MEMS actuator to achieve in-plane motion of the mirror (moves parallel to a plane of said at least one waveguide). In one implementation, the MEMS actuator is embodied as a known comb drive actuator. The phase adjustment techniques of the present invention may be employed in various optical devices, including wavelength selective optical switches that support multiple optical channels.

Abstract: The invention proposes a device for high-frequency and/or radio-frequency tuning comprising within one IC-package a first variable capacitor (C1) and at least one second capacitor (C2), each of the at least one second capacitor (C2) being fixed or variable respectively, at least one signal path connected to the first variable capacitor (C1) and providing at least one input and one output port (rf-port1, rf-port2) and at least one controllable switching means (SC2) for individually connecting and disconnecting at least one of the at least one second capacitor (C2) into the signal path or from the signal path, in particular in parallel to the first variable capacitor (C1).

Abstract: The invention comprises a method and apparatus for managing adjunct access and leased facilities in network management systems. The invention advantageously provides a continuous circuit by opportunistically using cross connect links to represent the connection of managed and non-managed portions of a circuit.

Abstract: The message waiting notification update system is operable in the serving Mobile Switching Center and, upon receipt of a message-waiting acknowledgement from the mobile subscriber station, updates the local copy of the subscriber's data in the Visited Location Register and forwards this information to the subscriber's Home Location Register. The Home Location Register stores this received data for use when the next successive Registration Notification is received from a new serving Mobile Switching Center or in response to the subscriber initiating a local access. When the serving Mobile Switching Center receives a Registration Notification message return result from the subscriber's Home Location Register and the message waiting notification count is the same as the count previously sent to the Home Location Register, the serving Mobile Switching Center does not have to transmit a message waiting notification over the forward control channel to the mobile subscriber station.

Abstract: A complete User Datagram Protocol (CUDP) is disclosed that reduces packet loss. Channel frame error information is used with a packet level forward error correction (FEC) coding technique to accommodate wireless multimedia traffic. Each packet, as well as the channel frame error information, is forwarded to a given application. The CUDP protocol further assists the FEC decoding process by forwarding the locations of corrupted frames to the FEC decoder. Maximal Distance Separable (MDS) codes can be applied to a group of packets, to achieve additional robustness. An MDS decoder utilizes the frame error information to recognize the erasures within each packet. The error information can be represented as a set of LTU error indicators associated with each packet (for FEC decoders requiring an erasure indicator). The error indicators point to the starting and ending location of the erroneous data. The error information can also be represented as a reformatted packet (for FEC decoders Recognizing Erasures).

Abstract: A flexible Boundary Scan test system is disclosed. The system includes an interpreter module operable to execute a program element selected from a plurality of program elements that include at least one instruction type having an interface to identify and execute selected functions wherein each of the selected functions has associated therewith at least one data information item. In one aspect of the invention, selected ones of the functions are composed of a plurality of functions. In another aspect of the invention, the instruction includes parameters and adornments for determining the selected function execution.

Abstract: In the method of determining an airlink modulation and coding scheme, at least one link quality indicator is compensated, and a modulation and coding scheme is read from a table using the compensated link quality indicator. In one embodiment, the at least one link quality indicator includes bit error probability (BEP).

Abstract: A telecommunication network and method of billing a first subscriber associated with a first party to a call for variable call charges normally billed to a second subscriber associated with a second party is provided. The method includes: providing a charge-all mode, connecting the call between the first and second parties, determining whether charge-all mode has been arranged for the first subscriber, determining whether charge-all mode has been arranged for the second subscriber, and, if charge-all mode has been arranged for at least one, but not both, of the first and second subscribers, billing the subscriber associated with the at least one subscriber for variable charges associated with the call. The telecommunication network includes a first network serving the first party and adapted to provide charge-all mode to the first subscriber and a second network serving the second party and adapted to provide charge-all mode to the second subscriber.

Abstract: A monolithic waveguide/MEMS switch is disclosed that has a waveguide portion and a MEMS mirror portion fabricated on a single substrate, such as a as a silicon-on-insulator wafer. The monolithic waveguide/MEMS switch adjusts the phase of an optical signal by varying the position of one or more moveable mirrors. The mirror portion includes a mirror having a reflective surface that is attached to at least one MEMS actuator to achieve in-plane motion of the mirror (moves parallel to a plane of said at least one waveguide). In one implementation, the MEMS actuator is embodied as a known comb drive actuator. The phase adjustment techniques of the present invention may be employed in various optical devices, including wavelength selective optical switches that support multiple optical channels.

Abstract: An orthogonal heterodyne in-band optical signal-to-noise-ratio (OSNR) monitoring method and apparatus that use the polarization characteristics of two narrow bandwidth filtered optical spectral components which is not only insensitive to the effects of polarization mode dispersion (PMD) and inter-channel cross-phase modulation (XPM) induced nonlinear polarization scattering, but also independent of bit rate and modulation format. The monitoring method is demonstrated for both linear and nonlinear systems.

Abstract: An InP on-chip polarization splitter is proposed base on an arrayed waveguide grating that is composed of waveguides having birefringence. The present invention also performs channel filtering and demultiplexing that is useful in WDM/DWDM applications. The required waveguide structure is formed using active-passive monolithic integration platforms, providing the integration of the polarization splitter with active devices as well as passive devices.