Abstract: An application monitor apparatus is provided that enables feedback to be sent to a transmitting terminal without relay processing of application data in the application layer. A packet transmission decision unit outputs to an application monitor unit and a packet transmitting unit only packets for which transmission is authorized by both the application monitor unit and the packet transmitting unit. When monitoring processing of the application monitor unit is slower than the rate of receiving packets at a packet receiving unit, the packet transmission decision unit sends feedback to the packet receiving unit to delay the transmission of packets.

Abstract: A datagram relaying apparatus includes a plurality of protocol terminating units, and a destination determining processor. The destination determining processor includes a path selecting section which determines a transfer destination route for a stream of packets received from any of the protocol terminating units. The path selecting section determines whether or not transfer of the received stream of packets to the transfer destination route is in an inhibition state, and selects another transfer destination route when the transfer of the packet to the transfer destination route is in the inhibition state.

Abstract: A communications apparatus for directly transferring payload data included in a received packet to an application memory area. The communications apparatus comprises an error check unit for checking the payload data for an error, a write processing unit for performing write processing for writing the payload data into the application memory area, and a protocol processing unit for causing the write processing unit to start write processing to write the payload data into the application memory without waiting for the completion of the error check, and upon detection of an error, returning a valid section in the application area that has been overwritten by write processing to an invalid section which has not stored normal data.

Abstract: To provide an engine software cooperation mechanism which avoids stopping the operation of a high-speed engine during timer monitoring processing. This system checks occurrence of a timeout event by directly accessing the content of a session data memory without regard to the locking state of a session. If detecting the state of timeout, the system requests execution of timeout processing via a timer transmission circuit. By timeout processing, the time of timeout and the present time are checked again to confirm whether a timer is not cancelled.

Abstract: A datagram relaying apparatus includes a plurality of protocol terminating units, and a destination determining processor. The destination determining processor includes a path selecting section which determines a transfer destination route for a stream of packets received from any of the protocol terminating units. The path selecting section determines whether or not transfer of the received stream of packets to the transfer destination route is in an inhibition state, and selects another transfer destination route when the transfer of the packet to the transfer destination route is in the inhibition state.

Abstract: A datagram relaying apparatus includes a plurality of protocol terminating units, and a destination determining processor. The destination determining processor includes a path selecting section which determines a transfer destination route for a stream of packets received from any of the protocol terminating units. The path selecting section determines whether or not transfer of the received stream of packets to the transfer destination route is in an inhibition state, and selects another transfer destination route when the transfer of the packet to the transfer destination route is in the inhibition state.

Abstract: A switch apparatus is provided with a plurality of input interfaces, a plurality of intermediate buffers; a plurality of output interfaces; an input-side switch providing connections between the input interfaces and the intermediate buffers; and an output-side switch providing connections between the intermediate buffers and the output interfaces. Each of the plurality of input interfaces is provided with a plurality of pointers for each of the output interfaces, each of the plurality of pointers containing a pointer value indicating one of the intermediate buffers. The plurality of input interfaces are each designed to select one of the plurality of pointers and to forward arriving cells to desired ones of the plurality of intermediate buffers starting from selected one of the plurality of intermediate buffers in response to a pointer value contained in the selected one of the plurality of pointers.

Abstract: A load balanced type switching apparatus includes input stages, intermediate stages connected with the input stages in a mesh manner, and output stages connected with the intermediate stages in a mesh manner.

Abstract: A packet switch scheduling apparatus in a packet communication apparatus is disclosed. Output schedulers select respective input lines, which are to be connected to a crossbar switch, for respective output lines. If previously selected input lines overlap each other, input schedulers select respective output lines for respective input lines, and output canceling information to those output schedulers which correspond to overlapping output lines that have not been selected. When the output schedulers are supplied with the canceling information, the output schedulers increments the value of request counters for the input lines corresponding to the input schedulers which have output the canceling information.

Abstract: A communications apparatus for directly transferring payload data included in a received packet to an application memory area. The communications apparatus comprises an error check unit for checking the payload data for an error, a write processing unit for performing write processing for writing the payload data into the application memory area, and a protocol processing unit for causing the write processing unit to start write processing to write the payload data into the application memory without waiting for the completion of the error check, and upon detection of an error, returning a valid section in the application area that has been overwritten by write processing to an invalid section which has not stored normal data.

Abstract: Methods and apparatuses for improved data transmission control protocols. Acknowledgment streams are used by a sender process to generate various estimates of eligible transmission rates that are fair to other processes competing for bandwidth across a common network. In addition, the acknowledgment streams are used in conjunction with various other standard transmission control protocol metrics to adapt a filter for use on the rate estimates. Additional improvements in throughput may no be had by measuring the overall capacity of the computer network using packet pair dispersion measurements and adaptive network probing. In addition, the methods may be adapted for both packet transmission and video streaming applications.

Abstract: A multi-layer class identifying communication apparatus, includes an input interface connected to input communication lines; a switch circuit; and an output interface connected to output communication lines. The input interface comprises an allocating section which determines a class identifier indicative of one of classes to which an IP packet belongs, from header data of the IP packet received through one of the input communication lines, and allocates an IP-QOS (Internet-Protocol-Quality-of-Service) code to the IP packet. The switch circuit selects one of the output communication lines based on a destination address of the IP packet, such that the IP packet is outputted from the output interface to the selected output communication output interface.

Abstract: An apparatus for scheduling packets for presenting a plurality of classes, includes (a) a buffer which accumulates received packets in each of the classes, (b) a token administrator which judges whether it is allowed to transmit a packet in each of the classes by virtue of a token associated with each of the classes, (c) a scheduler which determines a class to which a packet to be transmitted belongs, based on the judgment carried out by the token administrator, and (d) a controller which reads a packet of the class determined by the scheduler, out of the buffer, and transmits the thus read-out packet. The token administrator includes a single first circuit for carrying out subtraction of a token and a single second circuit for carrying out addition of a token, and carries out subtraction and addition of a token for each of the classes by means of the single first circuit and the single second circuit.

Abstract: An application monitor apparatus is provided that enables feedback to be sent to a transmitting terminal without relay processing of application data in the application layer. A packet transmission decision unit outputs to an application monitor unit and a packet transmitting unit only packets for which transmission is authorized by both the application monitor unit and the packet transmitting unit. When monitoring processing of the application monitor unit is slower than the rate of receiving packets at a packet receiving unit, the packet transmission decision unit sends feedback to the packet receiving unit to delay the transmission of packets.

Abstract: A datagram relaying apparatus includes a plurality of protocol terminating units, and a destination determining processor. The destination determining processor includes a path selecting section which determines a transfer destination route for a stream of packets received from any of the protocol terminating units. The path selecting section determines whether or not transfer of the received stream of packets to the transfer destination route is in an inhibition state, and selects another transfer destination route when the transfer of the packet to the transfer destination route is in the inhibition state.

Abstract: A datagram relaying apparatus includes a plurality of protocol terminating units, and a destination determining processor. The destination determining processor includes a path selecting section which determines a transfer destination route for a stream of packets received from any of the protocol terminating units. The path selecting section determines whether or not transfer of the received stream of packets to the transfer destination route is in an inhibition state, and selects another transfer destination route when the transfer of the packet to the transfer destination route is in the inhibition state.

Abstract: An apparatus for scheduling packets for presenting a plurality of classes, includes (a) a buffer which accumulates received packets in each of the classes, (b) a token administrator which judges whether it is allowed to transmit a packet in each of the classes by virtue of a token associated with each of the classes, (c) a scheduler which determines a class to which a packet to be transmitted belongs, based on the judgment carried out by the token administrator, and (d) a controller which reads a packet of the class determined by the scheduler, out of the buffer, and transmits the thus read-out packet. The token administrator includes a single first circuit for carrying out subtraction of a token and a single second circuit for carrying out addition of a token, and carries out subtraction and addition of a token for each of the classes by means of the single first circuit and the single second circuit.

Abstract: A transfer destination determining apparatus and method performing a load distribution in a network, where a plurality of transfer destination subjects are present as a transfer destination of a datagram, while the same collected flows are transferred to the same transfer destinations, the transfer destinations are allocated with respect to each of the collected flows. This apparatus has an extracting part extracting address and flow discrimination information, in the IP datagram; route solving part determining a transfer path based on the address information. When the determined path is a single path, the transfer destination is uniquely determined and the path is outputted to a post-staged apparatus, whereas when the path is a multi-path having a plurality of transfer destination subjects a multi-path number is outputted to a flow managing means which determines a transfer path corresponding, to a collected flow based on the received flow discrimination information and the multi-path number.

Abstract: A lightwave network data communications system having such an architecture that routing operation within a lightwave network is simplified, and a high-speed transfer process is attained in a large-scale basic network utilizing a wavelength division multiplexing (WDM) technology which accommodates internet traffics from a plurality of subscriber networks.

Abstract: A communication control unit is provided which is capable of retrieving a path regardless of a length of an address to be retrieved, of reducing a scale of its circuit, of achieving a high speed processing of retrieval and of preventing an increase in memory size required. The communication control unit is composed of a retrieval data managing circuit adapted to represent a node of a path tree corresponding to a path table by a split address obtained by setting-off a real address by one byte and a split mask length and to produce an address comparison byte composed of four stages obtained by setting-off a retrieving address by one byte and a next node selection byte, a nex-node selecting circuit adapted to decide a node to be retrieved next based oil the next node selection byte and a path retrieving circuit adapted to compare valid address portion showing a split mask length out of the split address with a split mask length portion of the address comparison byte.