Massachusetts Institute of Technology

Netapp, Inc.

Network Appliance, Inc.

Other

John D Moores

Salil A Parikh

Mark R Parquette

Gene M Ciancaglini

Muriel Medard

Kristin A Rauschenbach

Michael James Rydeen

James A Hart

Michael M Garofalo

Donald Proulx

William Proulx

Stephen R Chinn

Guy Oliveira

Steven Lumetta

Paul Marichal

Michael Lupinacci

Richard A Barry

Steven G Finn

Naimish S Patel

Agnes H Chan

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.

Multi-protocol network interface card

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.

Multiple access protocol system and related techniques for multi-gigabit optical wavelength division multiplexed local area networks

A switching device includes an ingress memory system having a VOQ-based design to provide an infrastructure for enabling fine-grained QoS and SLAs.

Network switching device ingress memory system

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.

Fault tolerant optical data communication network having auto discovery

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.

Integrated system and method for controlling telecommunication network data communicated over a local area network and storage data communicated over a storage area network

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.

Optical bit rate converter

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 S,and the first controller operating at a second speed S,. In one embodiment the first speed S,of the first feedback shift register is an integer multiple of the second speed S,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.

Pseudorandom noise sequence generator

A polarization desensitizing method and apparatus including a polarization analyzer separating a polarized input pulse into two orthogonally polarized components separated in time; and a nonlinear switch integrating the power of the two orthogonally polarized components over a predetermined time and producing an output pulse having a predetermined polarization. In one embodiment the polarization desensitizer includes a polarization analyzer in communication with a data source providing data pulses; a pulse generator; and a polarization converting switch in communication with both the polarization analyzer and the pulse generator, the polarization converting switch producing output pulses of a known polarization in response to the data pulses.

Polarization desensitizer

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.

Rational-harmonic apparatus and technique

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.

Growing community of inventors

Groton, MA, United States of America

John D Moores