Abstract: The present invention provides a communication network comprising a host network, a plurality of base stations, at least a mobile host capable of establishing links to the base stations, and a hierarchy-network of plural routers which are improved in transferring performances for ensuring continuous operations with a reduced load without packet loss.

Abstract: In order to more efficiently use port resources, which are finite global address resources assigned to an address translation device, the address translation device holds a session-port assignment table showing a correspondence between an existing session and a local endpoint (port resource) in the address translation device, and a port assignment rule indicating port usage about assignable ports. An address translation unit translates address information of a packet received according to the correspondence between the existing session and the port resource shown in the session-port assignment table, and assigns the port according to the port usage indicated by the port assignment rule for a packet for opening a new session. An assignment rule update unit changes a ratio of the port usage in the port assignment rule while the correspondence between the existing session and the port resource in the session-port assignment table is not changed.

Abstract: The present invention provides a communication network comprising a host network, a plurality of base stations, at least a mobile host capable of establishing links to the base stations, and a hierarchy-network of plural routers which are improved in transferring performances for ensuring continuous operations with a reduced load without packet loss.

Abstract: A computer system has: a virtual machine operating on a physical machine; and a management block operating on the physical machine and managing the virtual machine. The virtual machine has a specific function processing module that performs specific function processing with respect to a packet for transmission and a received packet. The management block has a virtual switch that relays a packet transmitted and received by the virtual machine. The virtual switch has an offload processing block that performs the specific function processing if the specific function processing is offloaded to the management block. If the specific function processing is offloaded from the virtual machine to the management block, the specific function processing module notifies the management block of processing information required for the specific function processing, and the offload processing block executes the specific function processing based on the processing information received from the virtual machine.

Abstract: A server includes a processor, a network adapter connected to the processor and a route switcher. The processor includes a virtual machine and a virtual switch relaying packets exchanged between the virtual machine and an exterior. The network adapter has a transfer function of transmitting and receiving packets to and from the virtual machine not through the virtual switch. The route switcher dynamically switches a flow of the packets transmitted and received by the virtual machine between first and second route pattern flows. And, the route switcher instructs the transfer function to process the first route pattern flow instructs the virtual switch to process the second route pattern flow.

Abstract: A module train determination block determines a module block being composed of at least one of a plurality of control application modules having different network control functions respectively. A plurality of attached data prepared for the plurality of control application modules are used. Each of the plurality of attached data indicates an operational parameter being referred or rewritten when the operation determined by a corresponding control application module is executed. The module train determination block refers to each attached data and determines a module train whose consistency is insured. A scheduling block executes the module train in turn and generates a single entry setting data indicating a sequence of the operation which corresponds to a sequence of network control devices.

Abstract: Access routers (100-1 and 100-2) perform packet transfer using an IP address and a port number between a global network allowing mutual access using the IP address and a network other than the global network. Port resource assigning device (400) manages the port number in units of IP addresses, and, when performing the packet transfer, assigns the port number managed by means of the IP address preliminarily provided for access routers (100-1 and 100-2). Access routers (100-1 and 100-2) perform packet transfer using the IP address preliminarily provided for access router (100-1 and 100-2) and the port number assigned by port resource assigning device (400).

Abstract: From a time point of last confirmation of operation of the working device 51 until a time point of next confirmation, the standby device 52 receives the same packet as that whose transfer processing is executed by the working device from the interface units 521-1˜521-n, processes the packet by the transfer unit 522 and holds the processed packet in the accumulation units 525-1˜525-n. The device monitors an operation state of the working device 51 by an advertisement transmitted by the working device 51 and upon reception of the advertisement, responsively abandons the packet held in the accumulation units 525-1˜525-n. When determining that the working device 51 stops by non-arrival of an advertisement for a predetermined time period, the device sends out the packet held in the accumulation units 525-1˜525-n and switches processing so as to itself operate as a working device.

Abstract: The present invention provides a communication network comprising a host network, a plurality of base stations, at least a mobile host capable of establishing links to the base stations, and a hierarchy-network of plural routers which are improved in transferring performances for ensuring continuous operations with a reduced load without packet loss.

Abstract: In order to more efficiently use port resources, which are finite global address resources assigned to an address translation device, the address translation device holds a session-port assignment table showing a correspondence between an existing session and a local endpoint (port resource) in the address translation device, and a port assignment rule indicating port usage about assignable ports. An address translation unit translates address information of a packet received according to the correspondence between the existing session and the port resource shown in the session-port assignment table, and assigns the port according to the port usage indicated by the port assignment rule for a packet for opening a new session. An assignment rule update unit changes a ratio of the port usage in the port assignment rule while the correspondence between the existing session and the port resource in the session-port assignment table is not changed.

Abstract: Load balancing manager assigns to each cluster member a filter rule so as to divide traffic processing by a predetermined rule. According to the assigned rule, each cluster member obtains a packet multicast by a neighbor node, on a data link with the neighbor node. Each cluster member detects a session of the obtained packet to perform predetermined processing such as recording and updating of a state and application of a firewall packet filter.

Abstract: An apparatus that analyzes execution paths of a target program includes a setting unit, a detecting unit, a determining unit, and a plurality of buffers. The setting unit stores a condition for determining whether or not to record events caused by execution of the target program. The detecting unit detects input and output data and events which are caused by execution of the target program. The determining unit determines whether or not to record the events based on the condition. The plurality of buffers store the events correlated with the input and output data if the determining unit determines to record the events.

Abstract: A protocol process to a reception traffic is executed by cluster members of a current use system and a backup system. The backup system discards the reception traffic subjected to the protocol process and only the current use system transfers the reception traffic to an AP. The AP makes an application process redundant in an independent method. The cluster member in charge of the protocol process to the reception traffic is determined by using a data in a lower layer and the cluster member in charge of the application process is determined by using a data in a higher layer after the protocol process.

Abstract: Distribution processing control unit determines a main processing range and a sub-processing range whose charges are taken by a cluster member to which the unit belongs. Among packets multicast to a cluster system, a filter hands over packets matching with the main processing range and the sub-processing range to a session processing unit. The session processing unit conducts session processing (including processing of updating session information stored in a holding unit). Thereafter, when the packet matches with the main processing range, the session processing unit hands the packet over to a packet forwarding unit and when the packet matches with the sub-processing range, abandons the packet. When a cluster member in charge of main processing of a packet whose sub-processing is taken charge of by the cluster member in question develops a failure, a failure recovery unit changes the sub-processing range to the main processing range.

Abstract: The present invention provides a communication network comprising a host network, a plurality of base stations, at least a mobile host capable of establishing links to the base stations, and a hierarchy-network of plural routers which are improved in transferring performances for ensuring continuous operations with a reduced load without packet loss.

Abstract: From a time point of last confirmation of operation of the working device 51 until a time point of next confirmation, the standby device 52 receives the same packet as that whose transfer processing is executed by the working device from the interface units 521-1˜521-n, processes the packet by the transfer unit 522 and holds the processed packet in the accumulation units 525-1˜525-n. The device monitors an operation state of the working device 51 by an advertisement transmitted by the working device 51 and upon reception of the advertisement, responsively abandons the packet held in the accumulation units 525-1˜525-n. When determining that the working device 51 stops by non-arrival of an advertisement for a predetermined time period, the device sends out the packet held in the accumulation units 525-1˜525-n and switches processing so as to itself operate as a working device.

Abstract: Each of cluster members (1-1) constituting a cluster system which functions as a router includes a session processor (15) and session state synchronization unit (16). If the session state of a session to which a packet input via a spare processing packet filter (13) belongs is not held in a session state holding unit (18), the session processor (15) newly registers the session state. When receiving a transfer rejection notification containing a session identifier of an unauthorized packet from a paired current cluster member, the session state synchronization unit (16) deletes a session state represented by the session identifier from the session state holding unit. If a cluster member which performs spare processing in a certain partial range has failed, the session state of this cluster member can be restored on a new cluster member added instead of the faulty cluster member, without largely increasing the communication cost.

Abstract: The present invention provides a communication network comprising a host network, a plurality of base stations, at least a mobile host capable of establishing links to the base stations, and a hierarchy-network of plural routers which are improved in transferring performances for ensuring continuous operations with a reduced load without packet loss.

Abstract: The present invention provides a communication network comprising a host network, a plurality of base stations, at least a mobile host capable of establishing links to the base stations, and a hierarchy-network of plural routers which are improved in transferring performances for ensuring continuous operations with a reduced load without packet loss.

Abstract: The invention provides a route updating method which reduces the flow rate of updating notifications, which are circulated in a network, to improve the scalability. A micromobility network includes routers connected in a tree connection and radio base stations connected to the routers in the lowest layer such that an updating notification of a route from a mobile terminal is repeated in order from a radio base station to successive higher order routers to update the route and a packet is distributed along the updated route. In the mobility network, directly lower order routers to each router are numbered to the numbers 1 to n with reference to the direct lower order router accommodation number n, and a route from the radio base station to the router in the highest layer represented by a route number composed of the numbers of the thus numbered routers is applied to the radio base station.