摘要:
A distributed memory computer system periodically performs memory copy among a plurality of computers by using general-purpose communication control devices and a transmission line of the CSMA/CD type. A master computer periodically generates a synchronizing packet, and transmits data for memory copy and normal data in a time slot immediately after the transmission of the synchronizing packet. Each computer other than the master computer transmits the data for memory copy and the normal data in its own time slot after the elapse of a predetermined time. The respective computers complete their transmissions within predetermined times. Since the time slots are assigned to the respective computers, the number of computers which may compete with each other on a transmission line can be restricted and each computer can be assured a periodic opportunity to transmit data.
摘要:
A network interface apparatus connected between a LAN adaptor possessed by a computer and a transceiver provided on a network includes a buffer memory for storing data, a first control circuit for communicating with the LAN adaptor, a second control circuit for communicating with the transceiver, and a processor for controlling the first and second control circuits to control the transfer of data between the LAN adaptor and the transceiver. The processor causes the buffer memory to store transmit data transmitted from the LAN adaptor and transmits the stored transmit data in the buffer memory to the transceiver in a transmission time zone which is allotted beforehand. The transmission time zone is determined by the processor on the basis of the reception of a synchronizing packet which is transferred on the network. Receive data received from the transceiver is selected by the processor so that only the selected receive data is sent to the LAN adaptor. A reference for the selection may include a protocol type, a port number on TCP/IP or the like.
摘要:
Communication control equipment for connecting a computer system to a network and supporting the computer system to set a plurality of connections on the network and perform parallel communication between computers. The communication control equipment includes an interface circuit for the computer system, a microprocessor for performing communication control processing, a local memory for storing programs and work data, a buffer memory for temporarily storing transmission and reception data, a DMA transfer unit for performing data transfer between a memory in the computer system and the buffer memory and protocol header transfer between the buffer memory and the local memory, a network controller for controlling transmission and reception of data to the network, and a header retrieval unit for predicting a protocol header of a frame to be next received in correspondence to each of a plurality of connections and retrieving a header corresponding to a protocol header of a received frame transferred by the DMA transfer unit.
摘要:
A network system having a plurality of interconnected networks each having a policy server. The policy server sets a quality-guaranteed path in the network according to a policy held in the policy server. The policy server includes: a policy holding unit to hold a policy defining a quality that can be guaranteed in its own network, or local network, for an inter-network communication; a policy publicizing unit to make public the policy held in the policy holding unit to the policy servers of other networks; a guaranteed quality calculation unit to calculate, from a policy publicized by a policy server of a network on a path between the local network and other network, a quality that can be guaranteed for the path between the local network and the other network; and a quality-guaranteed path setting unit to provide a quality-guaranteed path, the quality-guaranteed path having a guaranteed quality within the quality calculated by the guaranteed quality calculation unit for the path between the local network and the other network.
摘要:
Out of viewers of the same content, multi-user talking service is provided to only viewers who wish to enjoy the content in a large number of people. Only when an address of a terminal 4, 5 that has transmitted a request for participation in multi-user talking is registered in a viewer management DB (which manages viewers of contents), a content distribution/multi-user talking service center 1 registers the above-mentioned address into a participant management DB (which manages participants in multi-user talking) associating the address with identification information of a content that is registered in association with the address in question in the viewer management DB. Then, for each content, respective pieces of talking data received from addresses registered in association with identification information of said content in the participant management DB are synthesized to generate multi-user talking data, and generated multi-user talking data is transmitted to each of said addresses.
摘要:
There is provided an ATM controller which can support setting or alteration of protocol processing, and more greatly reduce the load (overhead) of software processing. The ATM controller performs the processing of an ATM layer and an AAL layer between a terminal and an ATM network, and comprises cell transmit control means for transferring a packet from a terminal side to an ATM network side while segmenting the packet into data cells, cell reception control means for reassembling data cells received from the ATM network side into a packet and transferring the packet to the terminal side, a rewritable memory for storing a firmware, and a microprocessor for performing a cell analysis and the processing corresponding to the analysis result.
摘要:
Switches create and manage routes with route control protocols such as BGP-4, PNNI, etc. and a route management apparatus is notified of the information of the routes, created by these protocols, and the route management apparatus verifies the validity of a route of which the apparatus is notified by a switch based on the route information of the whole network composed of the plurality of pieces of information given by respective switches and the management policy set by a network manager. In the verification of validity, it is confirmed that the transmitted data are able to arrive at the destination securely and the set route is not against the management policy, and the route-usage-permission-notice of a route confirmed of its validity by the route management apparatus is transmitted to respective switches. Thereby, in the route control of a network using a route control protocol, it is made possible to prevent the occurrence of an abnormal route caused by the difference in the speed of operations of respective switches or an erroneous setting of a switch.
摘要:
Disclosed herein is a computer system which comprises a plurality of input/output devices, an adapter device coupled to the plurality of input/output devices and a main processing unit for supplying an input/output request to each of the plurality of input/output devices through the adapter device. A plurality of input/output commands are respectively issued to the plurality of input/output devices from the main processing unit as one input/output start command. The adapter device specifies to which input/output devices the plurality of input/output commands included in the one input/output start command correspond. Further, the adapter device supplies input/output commands to the specified input/output devices respectively.
摘要:
Messages are transferred among a plurality of nodes by segmenting each of the messages into a plurality of packets on a transmission loop, and a receiver circuit which reassembles the segmented packets into the original message by the use of message buffers is comprised in each of the nodes, to detect whether or not a packet having arrived is from a registered mate, so that when the mate of the packet is not registered, the packet having arrived is registered anew in an empty field in any of the message buffers, thereby to perform message buffering, and that when no empty field exists, the packet having arrived is returned as being unreceivable, whereupon the sending mate having received the packet resends it.
摘要:
A resistor is provided with a plurality of turn parts whose corners have an obtuse flexional angle in order to improve the relative resistance precision. A ladder resistor can be formed with a plurality of such resistors connected in series, and various electronic devices are formed employing the ladder resistor.