Abstract: Disclosed is a method of tracing a program that comprises: providing a relational database data structure defining a plurality of fields configured to store program trace information; executing a program comprising a plurality of functions including calling a function from the program; extracting first trace data of the function and storing the first trace data in a portion of the plurality of fields; and after executing the program, extracting second trace data associated with the first trace data and storing the second trace data in remaining portions of the plurality of fields.

Abstract: A method of controlling a non-volatile memory device includes comparing the number of banks that are in operating states with a threshold value. If the number of the banks is smaller than the threshold value, data stored in a standby bank is read. If there is no bank having data to be read, a standby bank is programmed. If the number of the banks is equal to or greater than the threshold value or if the reading or the programming is performed, it is determined whether there is a reading or programming command to be performed. If there is the reading or programming command to be performed, the process is repeated from the comparing step. The programming may include programming of a most significant bit (MSB) page or a least significant bit (LSB) page.

Abstract: A method for scaling a dynamic voltage of a CPU is achieved by setting a voltage setting point for each of a plurality of code segments of a program, and profiling workload by measuring a workload variation of each of the code segments based on data that changes whenever measured, selecting a plurality of combinations, each having a plurality of voltage setting points, and calculating workload estimators corresponding to the voltage setting points of each of the selected combinations based on the workload variation measured in the workload profiling operation, selecting an optimal combination that consumes a least energy of the CPU based on the workload estimators, and determining whether a real time constraint is satisfied when an operating voltage is set based on the workload estimator corresponding to each of the voltage setting points of the optimal combination during runtime, and setting the operating voltage based on a result of the determination.

Abstract: Provided is a data flow management device managing a plurality of data flows. The data flow management device transmits data flows received from a plurality of sources to be transmitted to a plurality of destinations. The data flow management device includes a plurality of buffers outputting data flows received from the sources; and a transmitting unit transmitting the data flows output from the buffers to the destinations. The buffers do not output at a same time any two data flows received from two different sources to be transmitted to a same destination.

Abstract: Disclosed is a method of tracing a program that comprises: providing a relational database data structure defining a plurality of fields configured to store program trace information; executing a program comprising a plurality of functions including calling a function from the program; extracting first trace data of the function and storing the first trace data in a portion of the plurality of fields; and after executing the program, extracting second trace data associated with the first trace data and storing the second trace data in remaining portions of the plurality of fields.

Abstract: A method for scaling a dynamic voltage of a CPU is achieved by setting a voltage setting point for each of a plurality of code segments of a program, and profiling workload by measuring a workload variation of each of the code segments based on data that changes whenever measured, selecting a plurality of combinations, each having a plurality of voltage setting points, and calculating workload estimators corresponding to the voltage setting points of each of the selected combinations based on the workload variation measured in the workload profiling operation, selecting an optimal combination that consumes a least energy of the CPU based on the workload estimators, and determining whether a real time constraint is satisfied when an operating voltage is set based on the workload estimator corresponding to each of the voltage setting points of the optimal combination during runtime, and setting the operating voltage based on a result of the determination.

Abstract: An edge router for interfacing an optical label switched core IP network with client networks, which may be electronically switched and operate with different protocol. The core network has a limited number of ports, each with an edge router, which receives packets from one or more associated client networks and queues them according to egress port on the core network and optionally additionally according to attribute of service. When a queue has exceed a maximum packet length or a timeout limit assigned to the queue, the packets including their headers are assembled into a super packet for transmission across the core network in optical form, preferably using optical routers incorporating wavelength conversion of payloads and switching according to an attached label. The edge router at the egress port disassembles the super packet into constituent packets for respective destinations on the client network.

Abstract: An ultra-low latency optical router with a peta-bit-per-second total aggregate switching bandwidth, that will scale to a total connectivity of 1000 by 1000, and beyond by modular upgrades, that utilizes advanced optical technologies to achieve such high capacity with two to three orders of magnitude less volume and power requirements than the electrical router counter part, that serves as a universal engine to other optical routers being developed by vendors and researchers today, that can function in the context of circuit-switching, flow-switching, burst-switching, and packet-switching, that uses advanced wavelength conversion technology to effectively achieve three methods of contention resolution in the router: deflection in wavelength, deflection in space, and buffering in time, and that interfaces a local network to the Supernet.

Abstract: An all-optical regenerating circuit including a wavelength converter based on a Mach-Zehnder interferometer. The input signal is amplified and the interferometer adjusted to place the input signal across an entire monotonic portion of a sinusoidal transfer function to the wavelength-converted output signal. Retiming is effected by wavelength converters including pulsed laser sources of the output wavelength. A multi-wavelength regenerator may be integrated on a chip including two arrayed waveguides and an array of tunable lasers on parallel waveguides therebetween.

Abstract: An ultra-compact, room-temperature, continuous-wave infrared source that can rapidly tune over a very wide spectral range. The targeted spectral overages are 3 &mgr;m to 4 &mgr;m, 4 &mgr;m to 6 &mgr;m, 6 &mgr;m to 8 &mgr;m, and 8 &mgr;m to 12 &mgr;m. The spectral width of the infrared idler is expected to be ˜10 MHz. In particular, the invention is a monolithically integrated device which requires no external pump lasers or bulk optics for its operation. The invention uses difference-frequency-generation in a highly nonlinear optical semiconductor waveguide with which high power semiconductor lasers are integrated to internally provide the tunable pump and signal waves.

Abstract: An ultra-low latency optical router with a peta-bit-per-second total aggregate switching bandwidth, that will scale to a total connectivity of 1000 by 1000, and beyond by modular upgrades, that utilizes advanced optical technologies to achieve such high capacity with two to three orders of magnitude less volume and power requirements than the electrical router counter part, that serves as a universal engine to other optical routers being developed by vendors and researchers today, that can function in the context of circuit-switching, flow-switching, burst-switching, and packet-switching, that uses advanced wavelength conversion technology to effectively achieve three methods of contention resolution in the router: deflection in wavelength, deflection in space, and buffering in time, and that interfaces a local network to the Supernet.

Abstract: An ultra-low latency optical router with a peta-bit-per-second total aggregate switching bandwidth, that will scale to a total connectivity of 1000 by 1000, and beyond by modular upgrades, that utilizes advanced optical technologies to achieve such high capacity with two to three orders of magnitude less volume and power requirements than the electrical router counter part, that serves as a universal engine to other optical routers being developed by vendors and researchers today, that can function in the context of circuit-switching, flow-switching, burst-switching, and packet-switching, that uses advanced wavelength conversion technology to effectively achieve three methods of contention resolution in the router: deflection in wavelength, deflection in space, and buffering in time, and that interfaces a local network to the Supernet.

Abstract: Method and corresponding apparatus for extraction and rewriting of subcarrier multiplexed (SCM) signals such as optical header labels from a SCM/mixed baseband optical signal, amd routing of the baseband optical signal on the basis of the extracted header information. The method comprises applying an SCM/mixed baseband signal to a fiber Bragg grating (FBG) filter from which is extracted a modulated signal at information-bandwidth limited photoreceivers tapped to an optical signal path via an optical circulator (OC), causing the SCM optical signal to be stripped from the baseband optical signal. The method further comprises directing the baseband signal through a wavelength converting router in accordance with the information in the extracted SCM signal and writing a new SCM signal onto the baseband signal.

Abstract: An edge-emitting laser formed in an opto-electronic chip and having an emission wavelength determined by dielectric interference filter formed on opposing facets between which said laser extends. The two interference filter are each respective Fabry-Perot etalon filters having two interference mirrors sandwiching a resonant dielectric cavity layer so that the filter manifests a flat reflectance spectrum with a deep reflectance notch in its center. The two filters are fabricated with wavelengths of their notches differing by about 2%. The sum of the two filter transmittances represents round-trip cavity loss and has a double-peaked shape with a sharp minimum between the two notch wavelengths. The wavelength of the sum minimum determines the lasing wavelength without the need for a Bragg grating being incorporated within the chip. The invention can be applied to multi-wavelength edge-emitting lasers including multiple laser stripes by applying filters of different wavelengths to the ends of different stripes.

Abstract: An optical signaling header technique applicable to optical networks wherein packet routing information is embedded in the same channel or wavelength as the data payload so that both the header and data payload propagate through network elements with the same path and the associated delays. The header routing information has sufficiently different characteristics from the data payload so that the signaling header can be detected without being affected by the data payload, and that the signaling header can also be removed without affecting the data payload. The signal routing technique can be overlaid onto the conventional network elements in a modular manner using two types of applique modules. The first type effects header encoding and decoding at the entry and exit points of the data payload into and out of the network; the second type effects header detection at each of the network elements.

Abstract: A wavelength-interchanging cross-connect for use as an optical switch within a wavelength-division multiplexing (WDM) communications network in which multiple optical carrier signals at different optical wavelengths are switched in an all-optical process according to their wavelength. The cross-connect of the invention further allows the optical wavelength of the signal being switched to be changed to another WDM wavelength. The cross-connect includes a series of multi-wavelength 2.times.2 spatial optical switches. One serial path is directly connected between the spatial switches. The other serial path leads through intermediate wavelength-interchanging modules that interchange the carrier wavelengths of at least one pair of signals. Preferably, the wavelength interchanging is performed by difference frequency generation relying on second-order non-linear susceptibilities and a pump signal providing parametric gain.

Abstract: A waveguide having alternating regions of different crystallographic orientations, thereby providing quasi-phase-matching for a non-linear frequency conversion, in which two wafers with epitaxial layers thereon are bonded together having different, preferably opposed, crystallographic orientations. One wafer is etched away, and a grating is etched such that one part of the grating has the orientation of one wafer and the other part has the orientation of the other wafer. Thereafter, a waveguide structure is epitaxially deposited upon the differentially oriented template so that the waveguide is differentially oriented in its axial direction. Thereby, quasi-phase-matching non-linear effects can be achieved.

Abstract: A waveguide having alternating regions of different crystallographic orientations, thereby providing quasi-phase-matching for a non-linear frequency conversion, in which two wafers with or without epitaxial layers thereon are bonded together having different, preferably opposed, crystallographic orientations. One wafer is etched away, and a grating is etched such that one part of the grating has the orientation of one wafer and the other part has the orientation of the other wafer. Thereafter, a waveguide structure is epitaxially deposited upon the differentially oriented template so that the waveguide is differentially oriented in its axial direction. Thereby, quasi-phase-matching non-linear effects can be achieved. Several important devices can thereby be achieved, including a coherent optical source using frequency doubling and a frequency converter useful in wavelength division multiplexed communication, as well as others.

Abstract: An asymmetric Fabry-Perot modulator (AFPM) is disclosed having an operating wavelength in the 1.5 .mu.m region used for long-haul optical transmission. The AFPM includes electro-absorption material consisting of an Al.sub.x In.sub.y Ga.sub.1-x-y As multiple quantum well structure. An amplitude modulated optical signal is produced by modulating the bias voltage across the electro-absorption material between zero bias and the matching voltage that gives zero reflectivity from the cavity formed by the electro-absorption material and top and bottom reflectors. An amplitude modulated optical signal having a negative chirp parameter is produced by coating the top of the modulator with a high-reflectivity coating to reduce the voltage required to achieve the matching condition and then modulating the electro-absorption material between the matching voltage and a higher voltage.

Abstract: An all-optical wavelength converter comprising an optical waveguide of regions having differing non-linear optical susceptibilities such that the regions are quasi phase matched. An optical pumping signal is introduced in the waveguide, either input from the outside or is locally generated from a lasing active layer in the waveguide. Light having a first frequency is input to the waveguide and interacts with the optical pumping signal via the non-linear susceptibility to create light having a second frequency. Each of the regions has a length of one coherence length. That is, the input light and the pump light fall out of phase by 180.degree. in one coherence length. The modulation of the non-linear susceptibility can be accomplished, by disordering the anisotropic material forming the non-linear waveguide, by inverting the anisotropic crystal structure, or by launching an acoustic wave onto the waveguide so that the compression of the material periodically varies the non-linearities.