摘要:
An optical memory and an optical random and pseudo-random pattern generator for ultra-high-speed time-domain multiplexing multi-access networks are described. The optical memory and pattern generators include an optical ring resonator, an optical amplifier, a bistability generator, an optically-controlled stabilizing element, and a coupling element. Such devices are capable of storing high data rates for long periods of time.
摘要:
A switching device includes an ingress memory system having a VOQ-based design to provide an infrastructure for enabling fine-grained QoS and SLAs.
摘要:
A method and apparatus for a communications network that executes a medium access control (MAC) protocol that permits multiple access to a shared medium or shared switching fabric. The MAC protocol uses a bandwidth allocator to regulate access to the network by sending a permission message to a node, allowing it to transmit to a specific set of nodes for a specific length of time. The medium and switching fabric can carry one or more protocols, each of varying framing format and native bitrate. The switching fabric provides a connection-oriented bufferless data transport service that preserves frame ordering. An illustrative embodiment uses a slotted master/slave time-division multiplexed access (TDMA) scheme to allow flexible provisioning of network bandwidth.
摘要:
A pseudorandom sequence generator including a first feedback shift register having at least one input and at least one output and a first controller having an output in communication with the at least one input of the first feedback shift register; the first feedback shift register operating at a first speed S1 and the first controller operating at a second speed S2. In one embodiment the first speed S1 of the first feedback shift register is an integer multiple of the second speed S2 of the first controller. In another embodiment the first feedback shift register includes a shift register having an input, an output, and at least one tap; and a feedback function generator having a first input in communication with the at least one tap of the shift register, a second input in communication with the output of the first controller, and an output in communication with the input of the shift register; the feedback function generator includes at least one feedback function.
摘要:
An optical bit rate for communication systems. The optical bit rate converter converts an ultra-high speed optical data stream to a lower rate optical data stream. In one embodiment, the optical bit rate converter converts the ultra-high speed optical data stream to a lower rate optical data stream that can be detected and processed electronically. The optical rate converter includes a buffer presenting a repeating optical data bit pattern, an optical sampler presenting an optical sampling bit stream, and an optical correlator. The optical correlator has a first input in communication with the output of the buffer and a second input in communication with the output of the optical sampler. The optical correlator produces a rate-converted optical data bit stream at its output in response to the repeating optical data bit pattern produced by the buffer and the optical sampling bit stream produced by the optical sampler. In one embodiment, the buffer has a data input and stores an optical data bit stream received from a high speed optical data source. In another embodiment, the optical bit rate converter time dilates the repeating optical data bit pattern received from the buffer. In yet another embodiment, the optical bit rate converter demultiplexes the repeating optical data bit pattern received from the buffer. The invention also relates to a method for rate-converting an ultra-high speed optical data stream to a lower rate optical data stream.
摘要:
A method and apparatus for a communications network that executes a medium access control (MAC) protocol that permits multiple access to a shared medium or shared switching fabric. The MAC protocol uses a BANDWIDTH_ALLOCATOR to regulate access to the network by sending a permission message to a NODE, allowing it to transmit to a specific set of NODEs for a specific length of time. The medium and switching fabric can carry one or more protocols, each of varying framing format and native bitrate. The switching fabric provides a connection-oriented bufferless data transport service that preserves frame ordering. An illustrative embodiment uses a slotted master/slave time-division multiplexed access (TDMA) scheme to allow flexible provisioning of network bandwidth.
摘要:
A system for simultaneously transmitting and receiving multiple data messages on a unidirectional ring having a plurality of nodes coupled thereto is described. This technique utilizes a medium access (MAC) protocol for a multi-gigabit-per-second local-area optical wavelength division multiplexed (WDM) network that is particularly well suited for high-performance computing environments that need a network that provides quality of service and the ability to enforce service level agreements. The protocol uses an asynchronous, unslotted, tokenless, and collision-free access scheme that is arbitrated by a centralized scheduler. The embodiment is based on a folded-bus unidirectional ring that is passively optically tapped by the nodes to both transmit data onto the network and to receive data from the network. The system includes a scheduler based on a master/slave protocol that provisions and regulates data flow on the network, and uses a dedicated out-of-band control wavelength to broadcast scheduler directives to the nodes in the network.
摘要:
A modulated cavity including a cavity; a modulation source; and a modulator located with said cavity and in electrical communication with said modulation source. The modulation source overdrives the modulator with a period of modulation T.sub.mod substantially equal to T.sub.roundtrip (n+(p/q)).sup.-1. n, p, and q are integers. T.sub.roundtrip is the period of a pulse making one round-trip in the cavity. In one embodiment of the invention p and q are relatively prime. In another embodiment of the invention the optical response of the modulator includes the qth harmonic of (1/T.sub.mod). In yet another embodiment of the invention p/q is an integer. In still yet another embodiment of the invention p/q is a rational number.
摘要:
Interferometric fiber optic gyroscope. The gyroscope includes a pulsed light source for generating light pulses and a sense coil for receiving and trapping the light pulses travelling in clockwise and counter clockwise directions for a selected number of times around the sense coil. A detector receives the counter propagating light pulses to determine the phase shift between the two counter propagating light pulses, the phase shift being proportional to rotation rate of the sense coil.
摘要:
A fiber-optic networking system that can survive a break in the fiber and restore full connectivity to all nodes in the network. The network can detect the presence of a cut in the fiber, locate the cut, recover from the cut, and restore the communication capacity that was available before the cut. The network is also capable of automatically determining the existence and identity of the nodes in the network, the distance of the node from the headend, and the executing procedures to handle both planned and unplanned (i.e., during a fault) removal of nodes from the network.