Astute Networks, Inc.

Burroughs, Inc.

Xlnt Designs, Inc.

Intel Corporation

Tele Digital Development, Inc.

Ikanos Communications, Inc.

Fazil Ismet Osman

Simon John Knee

Brian David Petry

Ronald S Perloff

Robert M Grow

Christopher H Bracken

Vitek Zaba

David L Isaman

John L Bell

Ralph O Wickwire

Michael Anello

Roger S Moyers

Sally Cordes

Lawrence J Pollack

Robert J Peyser

Michael F Harris

A system and method of processing data and managing protocol timers in a stateful protocol processing system configured to process multiple flows of messages is disclosed herein. The method includes receiving a first plurality of messages of a first of the flows comporting with a first stateful protocol. The method further includes assigning a first protocol processing core to process event information derived from the first plurality of messages. A first flow timer associated with the first of the flows is set, and a first timeout expiration event is generated upon expiration of the first flow timer. The first timeout expiration event is then forwarded to the first protocol processing core, and a first flow state associated with the first flow is retrieved in response thereto.

System and method for timer management in a stateful protocol processing system

A method, system, and apparatus for processing messages according to one or more stateful protocols in a data communication system. Messages belonging to various communication flows (such as TCP transport layer 'connections') are processed according to a selected stateful protocol. Messages belonging to a single unified flow are distributed among different protocol processing cores (PPCs) at different times. Assignment of flows to PPCs is typically modifiable at the level of specific individual flows, permitting flexible load balancing between PPCs. The architecture of the system facilitates the method by providing a mix of pipelined and parallel processing structures.

High data rate stateful protocol processing

A system and method of processing data in a stateful protocol processing system ('SPPS') configured to process a multiplicity of flows of messages is disclosed herein. The method includes receiving a first plurality of messages belonging to a first of the flows comporting with a first stateful protocol. In addition, a second plurality of messages belonging to a second of the flows comporting with a second stateful protocol are also received. Various events of at least first and second types associated with the first flow are then derived from the first plurality of received messages. The method further includes assigning a first protocol processing core to process the events of the first type in accordance with the first stateful protocol. A second protocol processing core is also assigned to process the events of the second type in accordance with the first stateful protocol.

Multi-protocol and multi-format stateful processing

A method of flow control implemented by a system disposed to execute a protocol stack and an application is disclosed herein. The method includes configuring the system to operate in a push mode pursuant to which the protocol stack initiates the forwarding, to the application, of a first sequence of data packets received by the protocol stack. The system may also be configured to operate in a pull mode pursuant to which the application initiates the forwarding, to the application, of a second sequence of data packets received by the protocol stack. In a particular implementation the system may be configured to transition from the push mode to the pull mode, or vice-versa, in response to receipt at the protocol stack of a data packet bearing a specified sequence number.

System and method for flow control within a stateful protocol processing system

A system and method for managing shared state using multiple programmed processors within a stateful protocol processing system is disclosed herein. The disclosed method includes receiving a first message of a first flow comprised of a first plurality of messages, and deriving a first event from the first message. A first flow state characterizing the first flow is then retrieved. A first workspace portion of the first flow is assigned to a first protocol processing core, and a second workspace portion of the flow state is assigned to a second protocol processing core. The method further includes processing the first event using the first and second protocol processing cores. The first flow state may be defined at least in part by a plurality of protocol layers, in which case the first workspace portion and the second workspace portion correspond to different ones of such layers.

System and method for managing shared state using multiple programmed processors

A method and apparatus for facilitating failover of a stateful protocol connection is disclosed herein. The disclosed method includes receiving data sent by a first external entity in accordance with the stateful protocol connection. Acknowledgment of receipt of the data is withheld until a predefined operation involving the data has been performed. The method further includes transferring state information relating to the stateful protocol connection to a standby system. Once the predefined operation involving the data has been performed, the acknowledgment of receipt of the data is sent to the first external entity. This enables the stateful protocol connection to be failed over to the standby system with minimal or any data loss. In a particular implementation the predefined operation comprises committing the data to an application and receiving a send acknowledgment command from the application. In other implementations the predefined operation may comprise sending the data to a host entity and receiving confirmation that it has been received at the host.

System and method for facilitating failover of stateful connections

A switching fabric for transmitting digital data from a plurality of sources to a plurality of destinations is described. The switching fabric includes a plurality of input ports, a plurality of output ports and a plurality of switching sections. Each of the input ports receives data frames and partitions the received data payload of at least some of the frames into a plurality of associated data cells. Each of the output ports are coupled to at least one destination associated with the headers of the data frames. Each of the switching sections may be coupled to each of the input ports and each of the output ports for transmitting each of selected ones of the data cells from the at least one input port to one or more of the coupled output ports.

Switching fabric including a plurality of crossbar sections

An apparatus and method that allows a layer,&ldquo;spanning&rdquo; switch to switch data packets between subnets based upon layer,packet addresses. The &ldquo;spanning&rdquo; switch on a subnet can offer itself as a destination for data packets crossing to another subnet. Through a configuration process, a layer,switch is taught how to forward data packets between two stations on different subnets. The switch can then teach the two stations how to communicate via the layer,switch. The layer,switch is allocated a &ldquo;virtual&rdquo; IP address on each subnet for each station that wants to be involved in cross-subnet communications. More particularly, the invention includes a method for switching data packets between subnets of a network having frame and packet addresses, comprising the steps of: configuring a switching device coupled to each subnet to have a virtual packet address on each subnet associated with a packet address of a station on another subnet; providing a designated station on each subnet with the virtual packet address on such subnet and with an address for the associated station on another subnet; providing a frame address of a destination station on another subnet in response to requests from a designated station on a subnet relating to transmitting data packets to the destination station; and switching data packets from such designated station to the destination station through the switching device in response to the presence of the frame address in such data packets. The invention includes related apparatus and computer programs.

Switcher for spanning subnetworks

A method and apparatus for coupling a signal from one node to another node prepares a signal for transmission, performs error checking on such signal while simultaneously transferring such signal within a transmitting node, transmits the signal from the transmitting node, receives and formats the signal at a receiving node, including an identifying portion and a data portion, and directly stores the data portion in memory that is directly accessible by a user process executing in the receiving node while simultaneously performing error checking.

Method and apparatus for assisting data bus transfer protocol

A high performance bus and bus interface device for interconnecting numerous devices without using dedicated high current drivers at each device. The bus is synchronous and divided into a plurality of primary local busses and at least one global bus. Data can be transferred from a first device over a first primary local bus through a first global transceiver, over the global bus to a second global transceiver, and then to a second device through a second primary local bus. The bus is driven to a known state at the end of each burst of data transmitted by a device, before the bus is relinquished to another device. Buffers are provided in each device on the primary local bus which can be accessed by other devices. Buffer management includes: (1) determination by each transmitting device of buffer availability at each receiving device; (2) 'claiming' use by the transmitting device of a buffer in the receiving device for transfers from the transmitting device, including locking out other devices from writing to that buffer; (3) capability of the transmitting device to move received data to the buffer in the receiver; and (4) notification to all devices that the transfer is complete. The bus is used to transfer data between ports of a LAN bridge or switch. A dedicated lookup bus allows address lookup logic to be accessed without arbitrating for the data bus. A distributed CAM is used to perform address lookup functions.

Synchronous bus and bus interface device

Ring network security system with encoding of data entering a subnetwork

A system for securing communications between devices connected to a ring network. In accordance with the present invention, when a message frame is passed around the ring network, a gate keeper circuit associated with at least one port of a hub determines whether the message frame is intended for any of the nodes connected to that port. If the message frame is not intended for any of the nodes connected to that port, the message frame is encoded before it exits the hub through the port to traverse the subnetwork connected to the port, and decoded after it reenters the hub through the port. If and only if at least one node on the subnetwork connected to the port is intended to receive the message frame, then each node connected to that port can read the message frame.

A circuit which operates on input signals representing multiformatted sequences of idle characters, voice characters, and data characters comprises: a first state machine consisting essentially of a logic array, a register, and a counter. One section of the register is coupled to receive the input signals and another section of the register together with the counter is coupled to receive respective signals from the logic array. The logic array has input terminals coupled to receive signals from the register and the counter, and in response, generate control signals indicating in which format and which location therein each character is being received. Second, third, and fourth state machines are coupled to receive respective subsets of the control signals from the first state machine. The second, third, and fourth state machines are adapted to perform transmit and receive operations on the voice and data characters in response to the subset of control signals it receives; and each subset of the control signals is smaller in number than the input terminals of the logic array.

Circuit employing intercoupled state machines for transmitting and

A method of transmitting isochronous and nonisochronous data in a computer network in which multiple stations have respective input and output ports that are serially coupled together to form a loop includes the steps of: transmitting nonisochronous data from one station of the network and passing it through the remaining stations; periodically inserting into the nonisochronous data a lead control character followed by a trail control character and circulating the control characters twice around the network; increasing, in any station of the network that has isochronous data to send, the distance between the lead and trail control characters and sending isochronous data immediately before the trail control character as it passes through the station; subsequently decreasing the distance between the lead and trail control characters in each station of the network that performs the sending step by removing, from immediately behind the first lead control character to enter the station after the sending step begins, the same number of characters that it sent before the trail control character.

Method of inserting and removing isochronous data into a sequence of

A dynamic re-programmable logic array is disclosed which has an AND array disposed for receiving n input signals, an OR array providing k output signals on k output lines and m term lines and m bit lines coupling the AND and OR arrays, wherein the array comprises new and improved random access AND and OR arrays incorporating programmable charge storage elements. Refresh logic is also provided for periodically restoring the charge programmed on the charge storage elements.

Growing community of inventors

Escondido, CA, United States of America

Fazil Ismet Osman