Abstract: A method is provided for allocating bandwidth to a subscriber in a service provider domain that is part of a packet switched network such as the Internet, for example. In accordance with the method, a number of shares of bandwidth are assigned to the subscriber based on an agreement between the subscriber and a service provider. A subscriber identifier and the number of shares assigned thereto are distributed to the routers in the domain of the service provider. The routers will in turn allocate bandwidth to packets they receive based on the number of shares assigned to the subscriber transmitting or receiving the packet. The subscriber may include one or more different user terminals that aggregate traffic onto a single datastream. The shares assigned to the user may denote absolute amount of bandwidth, or alternatively, may denote a relative bandwidth allocation.

Abstract: A method and apparatus is provided that yields improved performance by modulating the optical phase and polarization of an optical signal with a periodic waveform having harmonic content that is more complex than that associated with a simple sinusoidal waveform. A phase modulator receives an optical signal onto which data has been modulated at a predetermined frequency. The phase modulator modulates the phase of the optical signal in a continuous manner with the periodic waveform with complex harmonics where the fundamental phase modulation frequency is equal to the same predetermined frequency at which the data is modulated onto the optical signal.

Abstract: A temporary self-adherence of the individual components in a stack of semiconductor components is accomplished by the use of adhesive bodies either separate from the solder preforms used in the stack or included within the solder in the form of a tacky paste. The adhesive bodies may comprise relatively high-purity water, and adhesion of the adjoining parts is achieved by the surface tension of the water. During a single heating step, preferably performed in a protective, non-oxidizing atmosphere, the water is completely evaporated while the solder preforms are heated to form the desired solder joints.

Abstract: A communications system is provided which supports asynchronous transfer mode (ATM) communications. An ATM multiplexer is located at a customer's premises and connected to customer premises voice and data equipment. A central office ATM multiplexer is connected to various different networks in the existing network infrastructure. The central office ATM multiplexer is preferably connected to networks such as a low-speed packet-switched network, a public circuit-switched network, a private line network, and a high-speed packet-switched network. The ATM multiplexer located at the customer premises preferably supports dynamic bandwidth allocation. Additional features provided by the communications system include the ability to provide different voice encoding schemes for different users based on calling party or called party information.

Abstract: A facility is provided for enhancing an operations support system so that, based on data generated as a result of an event occurring in an associated telecommunications network, the operations support system can predict the likelihood of the event occurring again in the network.

Abstract: Increased network security is provided by monitoring in real time one or more characteristics or attributes of telephone calls that are placed through the network and notifying the network customer (i.e., the party responsible for paying for the telephone calls), in real time, when the attributes are indicative of abnormal or fraudulent network usage. The network customer, once notified of the abnormal usage, is in a position to take steps to minimize unauthorized network usage. For example, the network customer can selectively block network usage, deny access to the network on a call-by-call basis, or trace the call to catch the unauthorized user while the call is still in progress.

Abstract: A lightwave communication system includes an optical distribution system for routing optical signals and a plurality of optical transmitters coupled to the optical distribution system. At least one of the optical transmitters has an amplified light emitting diode for generating an optical spectrum. At least one optical receiver is optically coupled to the optical distribution system.

Abstract: A method for forming an optical grating within a waveguide integrated on a substrate includes the step of depositing on a substrate successive layers of material constituting a waveguide such that the waveguide has a periodically varying width along a portion of its longitudinal axis. The deposition may be accomplished by depositing by selective area epitaxy at least some of the successive layers through a mask having a periodically varying width along at least one edge. The successive layers deposited through the mask may constitute a plurality of quantum well layers separated from each other by barrier layers which collectively form a multiple quantum well stack.

Abstract: A method is provided for reducing the polarization shift between different modes of an optical signal propagating in an optical grating having a plurality of waveguides extending in a common plane. The method includes the step of imparting curvature to the optical grating along a line that traverses the plurality of waveguides in a direction that is substantially perpendicular to the direction in which the optical signal propagates. The curvature varies in a nonuniform manner along the line to which it is imparted. The curvature may vary in a substantially linear manner along this line, which in some cases may define a symmetry axis of the grating. Sufficient curvature may be imparted to substantially eliminate the polarization shift. The curvature may be imparted by flexing the optical grating at two contact points respectively located near a longest and shortest of the plurality of waveguides.

Abstract: A method for reducing the inherent polarization shift caused by birefringence between the TE and TM modes of an optical signal propagating in an optical grating which has a plurality of waveguides includes the step of: irradiating the waveguides of the optical grating for different periods of time to induce a compensating polarization shift that substantially reduces the inherent polarization shift. If desired, a compensating polarization shift may be induced which not only reduces but also substantially eliminates the inherent polarization shift.

Abstract: A method and apparatus are described for reducing, in communication signals received by a local network from a remote network (FAR-IN signals), that energy content that is attributable to echoes of signals transmitted into the local network (NEAR-IN signals). This is achieved, in part, by generating a time-varying TEMPLATE signal which represents the smoothed energy content of NEAR-IN signals delayed according to the echo path and attenuated by an estimated echo transmission loss. A non-linear processor passes the FAR-IN signal substantially without attenuation if it exceeds the threshold derived at least in part from the TEMPLATE, but attenuates the FAR-IN signal if it lies within a defined range below the threshold.

Abstract: A semiconductor device is provided that includes an optical cavity that is designed to provide a prescribed resonant optical wavelength. The optical cavity includes a mirror structure deposited on top of a substrate and a multi-layer region such as an electroabsorptive region, for example, deposited over the mirror structure. A partial antireflective coating is deposited over the multi-layer region. The mirror structure and the multilayer region have a thickness variation sufficient to yield a resonant optical wavelength that deviates from the prescribed resonant wavelength. The partial antireflective coating has a non-uniform thickness variation that causes the resonant optical wavelength to shift substantially toward the prescribed resonant optical wavelength.

Abstract: The use of subscriber identifiers in a voice directed telecommunications system employing automatic speaker recognition is enhanced such that a group of subscribers may share the same identifier.

Abstract: Timing jitter problems are effectively eliminated in a soliton transmission system realized by deploying a series of optical filters in groups whose group average center frequency intentionally differs from the group average center frequency of other optical filter groups. The center frequency of the series of optical filter groups is translated along the desired length of the system in a predetermined manner such as frequency increasing, frequency decreasing, and combinations of both. This creates a transmission environment which is substantially opaque to noise while remaining perfectly transparent to solitons. By arranging the optical filters in groups, it is possible to simplify the system design by reducing the number of filters having different nominal center frequencies.

Abstract: An optical filter is formed from an optical frequency routing device having N inputs and N outputs, where N>1. A plurality of waveguides each couple one of the outputs to one of the inputs of the frequency routing device in a consecutive order to form a series of optically transmissive feedback loops. As a result of this arrangement, an input signal composed of a plurality of multiplexed optical frequencies directed to an input of the routing device is first demultiplexed to yield a sequence of demultiplexed frequency components which are directed to the outputs of the routing device. The demultiplexed frequencies may be rerouted back to the inputs of the routing device via the optical feedback loops between the outputs and the inputs. A remaining output that is not incorporated into one of the feedback loops is provided for receiving the resulting multiplexed output signal.

Abstract: A method and apparatus is provided for modulating the polarization of an optical signal. A polarization modulator receives an optical signal onto which data has been modulated at a predetermined frequency. The polarization modulator modulates the state of polarization of the optical signal at a frequency phase locked and equal to the same predetermined frequency at which the data is modulated onto the optical signal. The polarization modulation is performed so that the average value of the state of polarization over each modulation cycle is substantially equal to zero.

Abstract: An optical frequency translator includes a frequency routing device formed on a semiconductive wafer between two reflective facets forming a laser cavity. Waveguides associated with the device each contain an integrated optical amplifier selectively acting as a gate preventing the flow of optical energy through a respective waveguide or as a gain-providing element which amplifies optical energy flowing through a respective waveguide. When a selective one of the optical amplifiers is activated with bias current the optical energy produced by this current operates in conjunction with the optical energy of the input signal so that lasing action occurs between the reflective facets. The lasing action occurs along a predetermined path determined by the optical amplifier or amplifiers that are activated. The lasing action in this particular path is supported at a particular selected frequency. This particular frequency is the frequency to which the input signal is to be translated.

Abstract: A semiconductor laser has been developed which is capable of efficiently transmitting a predetermined number of modes to an external fiber or waveguide. The laser includes an active gain region disposed in a laser cavity that is formed in a semiconductor material. A lens and a waveguide are also located in the laser cavity. The lens receives optical energy generated by the active gain region and directs this energy into one end of the waveguide. The waveguide transmits the optical energy from the laser to an external fiber or waveguide. The waveguide may be either a single mode waveguide or a multimode waveguide that selects a predetermined number of modes from among all the modes generated by the active region. If a single mode waveguide is employed, the output energy is composed of the fundamental frequency generated by the active region. If a multimode waveguide is employed, the output energy is composed of the predetermined modes selected by the waveguide.