Abstract: A method for identifying, in a system including two or more computing devices that are able to communicate with each other, with each computing device having with a cache and connected to a corresponding memory, a computing device accessing one of the memories, includes monitoring memory access to any of the memories; monitoring cache coherency commands between computing devices; and identifying the computing device accessing one of the memories by using information related to the memory access and cache coherency commands.

Abstract: A processor issues a command to a memory through an electrical memory link and performs a process according to the command through the electrical memory link. The processor issues a routing command to an optical circuit switch (OCS) through an OCS control line. In response to the routing command, the OCS establishes a routing of an optical memory link from the processor to the BDM. In response to the establishment of the optical memory link from the processor to the BDM, the processor (or a BDM (internal/dedicated) controller) switches from performing the process through the electrical memory link to performing a process through the optical memory link (continuously without an interruption between the successive processes). Corresponding systems are also disclosed herein.

Abstract: A system including multiple nodes performing radio communication, wherein each node stores routing information, uses it to determine a transmission path, and performs cut-through transmission by transmitting and receiving packets to and from a node on the determined path through transmission and reception radio waves given a directivity by controlling their phases. In the system, time synchronization and transmission and reception of packet communication records are performed during a certain time period by carrying out the cut-through transmission while controlling phases of the radio waves so that all of the nodes form one or more closed loops. The node transmits and receives packets in accordance with routing information and a time frame assigned to each of the nodes as a time when each node is allowed to transmit and receive a packet, updates the routing information, and shares it with each node.

Abstract: A method of monitoring signals is disclosed, wherein a plurality of command signals and address signals are consecutively expressed, as a measurement target. The method includes setting a strobe timing that has a predetermined initial value; calculating an error rate by monitoring the plurality of command signals, in accordance with the strobe timing; monitoring the plurality of address signals, and calculating a burst rate from a difference between the consecutive plurality of address signals, in accordance with the strobe timing; identifying timing where the calculated error rate and calculated burst rate are both optimized; and in the event the timing where both the calculated error rate and calculated burst rate are optimized cannot be identified, altering a predetermined value of the set strobe timing, and repeating the calculating, monitoring, and identifying.

Abstract: A method of monitoring signals is disclosed, wherein a plurality of command signals and address signals are consecutively expressed, as a measurement target. The method includes setting a strobe timing that has a predetermined initial value; calculating an error rate by monitoring the plurality of command signals, in accordance with the strobe timing; monitoring the plurality of address signals, and calculating a burst rate from a difference between the consecutive plurality of address signals, in accordance with the strobe timing; identifying timing where the calculated error rate and calculated burst rate are both optimized; and in the event the timing where both the calculated error rate and calculated burst rate are optimized cannot be identified, altering a predetermined value of the set strobe timing, and repeating the calculating, monitoring, and identifying.

Abstract: A method of monitoring signals is disclosed, wherein a plurality of command signals and address signals are consecutively expressed, as a measurement target. The method includes setting a strobe timing that has a predetermined initial value; calculating an error rate by monitoring the plurality of command signals, in accordance with the strobe timing; monitoring the plurality of address signals, and calculating a burst rate from a difference between the consecutive plurality of address signals, in accordance with the strobe timing; identifying timing where the calculated error rate and calculated burst rate are both optimized; and in the event the timing where both the calculated error rate and calculated burst rate are optimized cannot be identified, altering a predetermined value of the set strobe timing, and repeating the calculating, monitoring, and identifying.

Abstract: A method of monitoring signals is disclosed, wherein a plurality of command signals and address signals are consecutively expressed, as a measurement target. The method includes setting a strobe timing that has a predetermined initial value; calculating an error rate by monitoring the plurality of command signals, in accordance with the strobe timing; monitoring the plurality of address signals, and calculating a burst rate from a difference between the consecutive plurality of address signals, in accordance with the strobe timing; identifying timing where the calculated error rate and calculated burst rate are both optimized; and in the event the timing where both the calculated error rate and calculated burst rate are optimized cannot be identified, altering a predetermined value of the set strobe timing, and repeating the calculating, monitoring, and identifying.

Abstract: A backplane, a method for making a backplane, and optical communication apparatuses. The backplane includes: a plurality of optical elements each selected from the group consisting of: (i) optical fibers, (ii) optical waveguides, and (iii) a combination thereof, where the plurality of optical elements have the same length, where the plurality of optical elements form at least one bundle, where the elements are bundled at both ends of the at least one bundle such that end portion lengths of the plurality of optical elements differ from each other, thus forming a broadcast-star topology, and where the plurality of optical elements is connected such that communication distance between at least two blades that can be inserted into the back plane is constant.

Abstract: A method, bus controller, and computer program product for arbitrating use of a communication bus for a certain one of a plurality of interconnected nodes that share the bus. The method includes the steps of: presenting a data frame on the transmitter and receiver side of the bus, where the certain node presents at the transmitter side, where the data frame has a embedded clock of a predetermined timing and a header field, synchronizing, by the certain node, with the embedded clock in the data frame at the receiving side of the bus, successively presenting, by the certain node, an idle pattern on the bus determined by a preassigned node ID, emitting light, by the certain node, on the bus at a predetermined timing preassigned to the certain node, and monitoring light emission on the bus that indicates a bus access request from another one of the nodes.

Abstract: A system including multiple nodes performing radio communication, wherein each node stores routing information, uses it to determine a transmission path, and performs cut-through transmission by transmitting and receiving packets to and from a node on the determined path through transmission and reception radio waves given a directivity by controlling their phases. In the system, time synchronization and transmission and reception of packet communication records are performed during a certain time period by carrying out the cut-through transmission while controlling phases of the radio waves so that all of the nodes form one or more closed loops. The node transmits and receives packets in accordance with routing information and a time frame assigned to each of the nodes as a time when each node is allowed to transmit and receive a packet, updates the routing information, and shares it with each node.

Abstract: A system including multiple nodes performing radio communication, wherein each node stores routing information, uses it to determine a transmission path, and performs cut-through transmission by transmitting and receiving packets to and from a node on the determined path through transmission and reception radio waves given a directivity by controlling their phases. In the system, time synchronization and transmission and reception of packet communication records are performed during a certain time period by carrying out the cut-through transmission while controlling phases of the radio waves so that all of the nodes form one or more closed loops. The node transmits and receives packets in accordance with routing information and a time frame assigned to each of the nodes as a time when each node is allowed to transmit and receive a packet, updates the routing information, and shares it with each node.

Abstract: A system and method for handling accesses by nodes connected to a ring network, using time division multiplexing (TDM). The system includes: nodes capable of receiving only an optical signal of a wavelength or positional space allocated to the node, and of transmitting optical signals of wavelengths allocated to other nodes; and a ring network that performs TDM transmission of optical signals. The ring network has slots for transmitting optical signals of individual wavelengths. Information indicates whether an optical signal to be transmitted exists in each of the slots. Nodes include means for updating the information indicating that the optical signal exists and determining means for updating the information and determining, on the basis of the information, whether to transmit the optical signal.

Abstract: Synchronized pseudo-random number outputs are produced at a transmitter and a receiver of a high-speed serial interconnection. At the transmitter, using logic XOR operations, each data word of parallel data is selectively scrambled with one of the pseudo-random numbers and transmitted via a high-speed serial interface. The receiver de-scrambles the received serial data stream and restores the parallel data.

Abstract: A method, bus controller, and computer program product for arbitrating use of a communication bus for a certain one of a plurality of interconnected nodes that share the bus. The method includes the steps of: presenting a data frame on the transmitter and receiver side of the bus, where the certain node presents at the transmitter side, where the data frame has a embedded clock of a predetermined timing and a header field, synchronizing, by the certain node, with the embedded clock in the data frame at the receiving side of the bus, successively presenting, by the certain node, an idle pattern on the bus determined by a preassigned node ID, emitting light, by the certain node, on the bus at a predetermined timing preassigned to the certain node, and monitoring light emission on the bus that indicates a bus access request from another one of the nodes.

Abstract: A backplane, a method for making a backplane, and optical communication apparatuses. The backplane includes: a plurality of optical elements each selected from the group consisting of: (i) optical fibers, (ii) optical waveguides, and (iii) a combination thereof, where the plurality of optical elements have the same length, where the plurality of optical elements form at least one bundle, where the elements are bundled at both ends of the at least one bundle such that end portion lengths of the plurality of optical elements differ from each other, thus forming a broadcast-star topology, and where the plurality of optical elements is connected such that communication distance between at least two blades that can be inserted into the back plane is constant.

Abstract: A system including multiple nodes performing radio communication, wherein each node stores routing information, uses it to determine a transmission path, and performs cut-through transmission by transmitting and receiving packets to and from a node on the determined path through transmission and reception radio waves given a directivity by controlling their phases. In the system, time synchronization and transmission and reception of packet communication records are performed during a certain time period by carrying out the cut-through transmission while controlling phases of the radio waves so that all of the nodes form one or more closed loops. The node transmits and receives packets in accordance with routing information and a time frame assigned to each of the nodes as a time when each node is allowed to transmit and receive a packet, updates the routing information, and shares it with each node.

Abstract: A system and method for handling accesses by nodes connected to a ring network, using time division multiplexing (TDM). The system includes: nodes capable of receiving only an optical signal of a wavelength or positional space allocated to the node, and of transmitting optical signals of wavelengths allocated to other nodes; and a ring network that performs TDM transmission of optical signals. The ring network has slots for transmitting optical signals of individual wavelengths. Information indicates whether an optical signal to be transmitted exists in each of the slots. Nodes include means for updating the information indicating that the optical signal exists and determining means for updating the information and determining, on the basis of the information, whether to transmit the optical signal.

Abstract: A system for detecting and correcting invalid calculation results due to a timing violation. A processor compares results of an instruction simultaneously executed by a first arithmetic pipeline and a second arithmetic pipeline of the processor. In the second arithmetic pipeline, the critical stage of the first arithmetic pipeline is divided to multiple stages. A first result calculated by the first arithmetic pipeline is speculatively executed within the processor. The second arithmetic pipeline calculates a second result. The processor compares the second result to the first result. When the results are identical, the first result is assigned as the final result with a complete status. When the results do not match, the processor replaces the first result with the second result. The processor may then cancel the speculatively executed instruction and issue the second result as a final result. The processor may then restart subsequent instructions using the second result.

Abstract: Synchronized pseudo-random number outputs are produced at a transmitter and a receiver of a high-speed serial interconnection. At the transmitter, using logic XOR operations, each data word of parallel data is selectively scrambled with one of the pseudo-random numbers and transmitted via a high-speed serial interface. The receiver de-scrambles the received serial data stream and restores the parallel data.

Abstract: A node terminal including an internal memory for saving a program transmitted from a server, a CPU for executing the program, a hash value calculating section for performing an operation of the program using a specified hash function when the execution of the program is completed, and a digital signature executing section for digitally signing the program operated using the hash function and the execution result of the program, using a secret key peculiar to the node and saved in a secret key storage, and a microprocessor capable of guaranteeing that the content of a memory is not unjustly falsified during the execution of the program.