Emc Corporation

The Charles Stark Draper Laboratory, Inc.

Almir D Davis

Christopher S MacLellan

Stephen Lawrence Scaringella

Philip S Babcock, Iv

Jeffrey Kinne

Matthew Sullivan

David Iwatsuki

Avinash Kallat

William Joseph Trinkle, Jr

Donald E Gustafson

Richard T Berthold

Imran Khan

Roger J Wilmarth

William F Baxter

Michael Sgrosso

William J Trinkle

Philip S Babcock

Philip S Iv Babcock

Philip S Babcock Iv

A linear wireless sensor network includes network nodes having monotonically varying network node identifiers along each branch of the network. The network identifiers enable the nodes to forward network packets without use of routing tables. Low duty cycle wireless communication protocols enable network packets to be routed to all nodes of very large networks while consuming very little electrical power. Broadcast, rather than unicast, transmissions between nodes take advantage of favorable signal propagation conditions to forward messages using largest possible hops, skipping over nodes when possible, as well as automatically adapting to time- or spatially-varying conditions. A group of network packets is broadcast and forwarded by a most distant receiving node that received all packets of the group. A receiving node's clock is automatically adjusted, based on which packet(s) of a group of packets was received. A sending node synchronizes near-by receiving nodes. Nodes are provisioned over-the-air, with built-in scheduling. Health and welfare information piggybacks on other network traffic.

Wireless network for sensor array

A linear wireless sensor network includes network nodes having monotonically varying network node identifiers along each branch of the network. The network identifiers enable the nodes to forward network packets without use of routing tables. Low duty cycle wireless communication protocols enable network packets to be routed to all nodes of very large networks while consuming very little electrical power. Broadcast, rather than unicast, transmissions between nodes take advantage of favorable signal propagation conditions to forward messages using largest possible hops, skipping over nodes when possible, as well as automatically adapting to time- or spatially- varying conditions. A group of network packets is broadcast and forwarded by a most distant receiving node that received all packets of the group. A receiving node's clock is automatically adjusted, based on which packet(s) of a group of packets was received. A sending node synchronizes near-by receiving nodes. Nodes are provisioned over-the-air, with built-in scheduling. Health and welfare information piggybacks on other network traffic.

Defects in ferromagnetic materials are detected and characterized by analyzing the items' magnetic fields to find portions of the magnetic fields that differ in characteristic ways from residual magnetic fields generated by non-defective portions of the items. The portions of the magnetic fields that differ in the characteristic ways correspond to locations of the defects. The residual magnetic fields correspond to portions of the items distant from the defects. The defect characterization may include volume of material lost due to each defect and/or width and/or depth of each defect.

System and method of measuring defects in ferromagnetic materials

A data transfer system includes a PCI Express transaction layer having an input for serially receiving posted and non-posted request packets and completion packets; an application layer coupled to the PCI Express transaction layer for receiving posted and non-posted request packets and completion packets from the PCI Express transaction layer; a first transmission interface coupling the application layer to the PCI Express transaction layer; and a second transmission interface coupling the application layer to the PCI Express transaction layer. The PCI Express transaction layer transmits posted and non-posted request packets to the application layer over the first transmission interface and transmits completion packets to the application layer over the second transmission interface.

Method and system for processing packet transfers

A system for arbitrating a transmission of data includes a number K of transmitters, a request signal transmission device, a device valid signal transmission device, and a data valid logic device, wherein a transmitter asserts a request signal to request permission to begin a data transmission and transmits transmission-identifying information to a receiver. The data valid logic device deasserts a data valid signal based on the state of a wait signal, thereby preventing a transmission of data from each of the K transmitters at one clock cycle after a clock cycle at which the data signal is deasserted. An arbitration logic device of the receiver selects one of the number K of transmitters to grant permission to transmit data to the receiver and outputs an arbitration signal to a wait logic device instructing the wait logic device to deassert the wait signal of the selected trnasmitter.

Method and system for arbitrating data transmissions

A data packet arbitration system for routing data transfers from a plurality of clients to a data transmission line is described. The system includes multiple arbitration stages for transferring data from the plurality of clients to the data transmission line. Data transfers are routed through the system based on arbitration logic that prioritizes by function in a primary arbitration stage and by client in a subsequent arbitration stage.

Data packet arbitration system

A data flow management system and method in which an application and its clients are made aware of the available credits for each type of transfer before the transfer is attempted. This enables the clients to transmit packets only when the RX side has issued a sufficient number of credits to insure that the transmission will not be stalled. The invention eliminates the need for FIFO buffers in the PCI-Express core, since the application will not transmit packets to the core until the required number of credits for the particular transfer type is available. Therefore, packet transmissions do not require buffering in the core, as they are only sent when they can be sent all the way through the core to the link. The efficient back-to-back transfer support enabled by this protocol increases the overall throughput and efficiency of the system as transfers through the application interface have fewer gaps therebetween, because the credit management protocol with its back-to-back feature reduces the idle times between packets traversing the application interface. An enhanced Quality of Service feature is also introduced by creating an environment where the low-latency packets can receive a highest attention and the lowest transmission wait time.

Method and system for managing data flow in a data transmission system

A data flow management system and method in which the application and its clients are made aware of the available credits for each type of transfer before the transfer is attempted. This enables the clients to transmit packets only when the RX side has issued a sufficient number of credits to insure that the transmission will not be stalled. The invention eliminates the need for FIFO buffers in the PCI-Express core, since the application will not transmit packets to the core until the required number of credits for the particular transfer type is available. Therefore, packet transmissions do not require buffering in the core, as they are only sent when they can be sent all the way through the core to the link. The efficient back-to-back transfer support enabled by this protocol increases the overall throughput and efficiency of the system as transfers through the application interface have fewer gaps therebetween, because the credit management protocol with its back-to-back feature reduces the idle times between packets traversing the application interface. An enhanced Quality of Service feature is also introduced by creating an environment where the low-latency packets can receive a highest attention and the lowest transmission wait time.

Data transmission method and system using credits, a plurality of buffers and a plurality of credit buses

A data packet routing mechanism including a plurality of clients for issuing read requests to a host device, the read requests each including a TAG field for identifying which of the plurality of clients issued a particular read request, wherein a completion response corresponding to the particular read request, including the TAG field, is issued from the host to the client that sent the read request, the plurality of clients being organized into M groups, each group including a predetermined number of clients; a first level routing device having an input for receiving completion responses from the host and a plurality of outputs for transmitting completion responses; and a plurality of second level routing devices, each being coupled to the plurality of clients in one of the M groups, and having an input for receiving completion responses from the first level routing device and a plurality of outputs, each output for transmitting completion responses to one of the plurality of clients in the group. The TAG field associated with each completion response includes a predetermined number of bitfields, a first bitfield of the TAG field being read by the first level routing device and providing the first level routing device with an identity of the second level routing device to which the completion response is to be transmitted, to which second level routing device the first level routing device transmits the completion response, and a second bitfield of the TAG field being read by the second level router device that receives the completion response from the first level routing device, the second bitfield providing the second level routing device with the identity of the client within the group to which the completion response is to be transmitted, to which the second level routing device transmits the completion response.

Data packet routing mechanism utilizing the transaction ID tag field

A system for detecting transmission errors in a data transmission system includes a receiver for receiving a data packet transmitted thereto by a corresponding transmitter and transmitting the data packet to a destination device and an error detection device for receiving a plurality of protocol signals that control the operation of the transmitter and the receiver. The error detection device applies at least one predetermined rule to the protocol signals, wherein a violation of the at least one rule by the protocol signals indicates that an error in the transmission of the packet has occurred, and asserts an error signal when the at least one rule has been violated by the protocol signals. The system further includes a packet filtering device coupled to receive the error signal from the error detection device and the data packet from the receiver, wherein, upon receiving the asserted error signal, the packet filtering device terminates the transmission of the data packet to the destination device.

Method and system for detecting transmitter errors

A system for transferring data packets between a data packet transfer core and a number of clients of an application layer, including an interface between the data packet transfer core and the application layer for transferring data packets from the packet transfer core to a first client and a second client. The data packet transfer core includes a number of core buffers for receiving data packet transfers input to the data packet transfer core. Each of the number of core buffers include a cut-through data path including a register and a bypass data path, the bypass data path transferring data packets from an input to the register to an output of the register without passing through the register. The system further includes a first data path from the first interface to the first client and a second data path from the interface to the second client, the second data path including an application layer buffer having an input coupled to the interface and an output coupled to the second client, the application layer buffer being for storing data packets transmitted to the second client when data packets are transmitted to the second client at a rate that is faster than the second client is able to receive the data packets. In a first mode of operation, data packets transmitted from the data packet transfer core to the first client are transferred through the bypass data path of at least one of the number of core buffers, over the interface and directly to the first client over the first data path.

Method and system for improving the latency in a data transmission system

Low latency data transmission method and system

A data transfer device is disclosed for writing data to and reading data from a disk drive system through a plurality of ports of the data transfer device. The data transfer device includes a first buffer for serially receiving, from a host system, control portions of data read requests and data write transfers; a second buffer for serially receiving, from the host system, data portions of data write transfers received by the first buffer; and N temporary storage devices, wherein N is a positive integer, coupled to the first buffer and the second buffer, the N temporary storage devices for parallelly receiving and temporarily storing consecutive control portions of the data read transfers and data write transfers from the first buffer. Up to N of the data read transfers and data write transfers are transferred to the disk drive system through the plurality of ports simultaneously.

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Quincy, MA, United States of America

Almir D Davis