An improved system for accessing data within a distributed data storage network (“DDSN”) is disclosed. In a system implementing the disclosed invention, traffic is routed to individual slice servers within the DDSN in accordance with objective criteria as well as user-defined policies. In accordance with one aspect of the disclosed invention, when a data segment is written to a DDSN, the segment is divided into multiple data slices, which are simultaneously transmitted to different slice servers. In accordance with another aspect of the disclosed invention, when a data segment is read from a DDSN, a list of slice servers, each containing a data slice that could be used to reconstruct the requested data segment, is assembled, and sorted in accordance with a preference rating assigned to each of the slice servers. Sufficient data slices to reconstruct the data segment are then read in accordance with the preference ranking of the slice servers.

Smart access to a dispersed data storage network

A billing process is disclosed for an information dispersal system or digital data storage system. The original data to be stored is separated into a number of data 'slices' or shares (22, 24, 26, 28, 30, and 32). These data subsets are stored on separate digital data storage devices (34, 36, 38, 40, 42, and 44) as a way of increasing privacy and security. A set of metadata tables are created, separate from the dispersed file share storage, to maintain information about the original data size of each block, file or set of file shares dispersed on the grid.

Billing system for information dispersal system

A block-based interface to a dispersed data storage network is disclosed. The disclosed interface accepts read and write commands from a file system resident on a user's computer and generates network commands that are forwarded to slice servers that form the storage component of the dispersed data storage network. The slice servers then fulfill the read and write commands.

Block based access to a dispersed data storage network

A system, method, and apparatus for implementing a plurality of dispersed data storage networks using a set of slice servers are disclosed. A plurality of information records are maintained, with each information record corresponding to a dispersed data storage network. The information record maintains what slice servers are used to implement the dispersed data storage network, as well as other information needed to administer a DDSN, such as the information dispersal algorithm used, how data is stored, and whether data is compressed or encrypted.

Virtualized data storage vaults on a dispersed data storage network

An architecture for a line card in a network routing device is provided. The line card architecture provides a bi-directional interface between the routing device and a network, both receiving packets from the network and transmitting the packets to the network through one or more connecting ports. In both the receive and transmit path, packets processing and routing in a multi-stage, parallel pipeline that can operate on several packets at the same time to determine each packet's routing destination is provided. Once a routing destination determination is made, the line card architecture provides for each received packet to be modified to contain new routing information and additional header data to facilitate packet transmission through the switching fabric. The line card architecture further provides for the use of bandwidth management techniques in order to buffer and enqueue each packet for transmission through the switching fabric to a corresponding destination port. The transmit path of the line card architecture further incorporates additional features for treatment and replication of multicast packets.

Pipelined packet switching and queuing architecture

A distributed memory switching hub interconnecting heterogeneous local area networks operating at different transmission speeds for receiving, storing and forwarding frames of data The distributed memory switching hub employs a distributed memory architecture in which memory storage for frames of data received and to be transmitted is located at each low speed LAN port of the distributed memory switching hub A distributed memory architecture renders unnecessary the need for a central programmable processor or shared common memory to store and forward frames received by the distributed memory switching hub

Distributed memory switching hub

A packet switching device having a central shared memory and a number of medium access controllers each coupled to a communications medium to exchange data packets, and a controller coupled to each medium access controller via a data path to exchange data packets with the media access controller. The controller has a number of data path controllers each connected to each medium access controller to exchange a corresponding portion of the data packets with the medium access controller. The data path controllers each have a number of buffers to hold the portion of the data packets exchanged with the corresponding medium access controller. Each data path controller has a selector that selects the buffer from which to exchange the portion of the data packets with the central shared memory and control logic that controls the selector to concurrently select the buffer corresponding to the same medium access controller.

Data path architecture for a LAN switch

A network interconnect device (100) and message exchange protocol for forwarding data among packet forwarding devices (105) are provided. According to one aspect of the present invention, data is forwarded between a first and second packet forwarding device (105) coupled to an interconnect device (100). The interconnect device (100) receives a menu message from the first packet forwarding device that indicates one or more types of data that are awaiting transmission on the first packet forwarding device (105). Based upon the menu message, the interconnect device (100) transmits an order message selecting a type of data of the one or more types of data awaiting transmission to the first packet forwarding device (105). The interconnect device (100) receives a message from the first packet forwarding device (105) containing data of the type selected by the order message. The interconnect device (100) then forwards the data to the second packet forwarding device.

Network interconnect device and protocol for communicating data among packet forwarding devices

A repeater in a LAN maintains a count of collisions and retransmission attempts for each node coupled to the repeater since that node's last successful packet transmission. The count is used to prioritize which of the nodes involved in a subsequent collision will be allowed to continue transmitting. The time at which data packets from the nodes arrive at the repeater will vary according to the propagation delay attributed to the varying lengths of the communication medium between each of the nodes and the repeater. For the repeater to arbitrate among the nodes that begin transmitting, it is useful to receive the data packets from each node at the same time. The repeater automatically equalizes the transmission delay. The repeater buffers the data packet received from each node until sufficient time has elapsed to begin receiving a data packet from each node that is attempting to transmit a data packet during the current arbitration interval. For each node, the repeater maintains a slot time counter. The backoff time following a collision is measured in increments of slot time, so using the slot time counter for a node allows the repeater to predict when it will receive a data packet from a node that is currently backed off. When a node has an opportunity to attempt transmitting a data packet at each slot time, the repeater determines if that node is going to attempt to transmit a data packet before deciding which node will be allowed to transmit a data packet.

Method and apparatus for predicting and controlling data transmission in a CSMA/CD LAN

A message exchange protocol for interconnecting packet forwarding devices through an intermediate network interconnect device is provided. According to one aspect of the present invention, a method is provided for communicating data between packet forwarding devices. The presence of an interconnect device that is coupled between a first packet forwarding device and a second packet forwarding device is detected by recognizing a configuration sequence, for example. After the link between the interconnect device and the first packet forwarding device is established, the first packet forwarding device receives a command from the interconnect device requesting the types of data that are pending on the first packet forwarding device. Responsive to the command, the first packet forwarding device transmits a "menu" including information indicating the availability of one or more types of data that are awaiting transmission to the interconnect device. An "order" is received by the first packet forwarding device from the interconnect device. The order includes information identifying a type of data being requested by the interconnect device. Responsive to the order, the first packet forwarding device transmits a message which contains data of the type identified by the order to the interconnect device.

Herb Schneider

Papers

Distributed memory switching hub

Data path architecture for a LAN switch

Network interconnect device and protocol for communicating data among packet forwarding devices

Method and apparatus for predicting and controlling data transmission in a CSMA/CD LAN

Protocol for communicating data between packet forwarding devices via an intermediate network interconnect device