Abstract: A failure location specification method executed including retrieving first setting information indicating a setting of a forward communication of a round trip between a first virtual machine and a second virtual machine, the forward communication being a communication from the first virtual machine to the second virtual machine, retrieving second setting information indicating a setting of a backward communication of the round trip, the backward communication being a communication from the second virtual machine to the first virtual machine in response to the forward communication, when the second setting information indicates that a communication between the first virtual machine and the second virtual machine is not established, retrieving third setting information and fourth setting information based on the first setting information, and specifying a failure location based on a pattern indicating a communication state and a plurality of reference patterns corresponding to each of a plurality of locations.

Abstract: A method includes: determining a group in which communication between virtual machines belonging to the group is not permitted by referring information regarding communication rules on virtual machines belonging to individual groups; storing deployment information indicating dispersed deployment in association with identification information on the determined group; determining whether the deployment information associated with identification information on a first group is stored when receiving an instruction to deploy a first virtual machine belonging to the first group; and determining a target physical machine in which the first virtual machine is to be deployed from among one or more physical machines in which a second virtual machine other than the first virtual machine belonging to the first group is not running out of physical machines when determining that the deployment information is stored in association with the identification information on the first group.

Abstract: A method of controlling a virtual router includes: starting first and second virtual routers where a same address is set, on first and second networks; constructing, with respect to a plurality of virtual machines arranged in plural networks, a first virtual network that establishes coupling between first one or more virtual machines and coupling between the first one or more virtual machines and the first virtual router, and establishes coupling between second one or more virtual machines and coupling between the second one or more virtual machines and the second virtual router, the first one or more virtual machines being arranged on the first network, the second one or more virtual machines being arranged on the second network; constructing a second virtual network that establishes coupling between the first virtual router and the second virtual router; and creating and setting routing tables corresponding to the first and second virtual routers.

Abstract: A non-transitory computer readable storage medium storing therein a program for causing a computer to execute a process, the process includes, receiving an inquiry of route information of a communication packet from a first virtual machine to a second virtual machine from a first virtual router relaying the communication packet from the first virtual machine, generating the route information including network identification information of a physical machine equipped with the second virtual machine based on identification information of the second virtual machine and constitution information including network identification information of the physical machine equipped with the second virtual machine, and transmitting the route information to the first virtual router.

Abstract: A method of controlling a virtual router includes: starting first and second virtual routers where a same address is set, on first and second networks; constructing, with respect to a plurality of virtual machines arranged in plural networks, a first virtual network that establishes coupling between first one or more virtual machines and coupling between the first one or more virtual machines and the first virtual router, and establishes coupling between second one or more virtual machines and coupling between the second one or more virtual machines and the second virtual router, the first one or more virtual machines being arranged on the first network, the second one or more virtual machines being arranged on the second network; constructing a second virtual network that establishes coupling between the first virtual router and the second virtual router; and creating and setting routing tables corresponding to the first and second virtual routers.

Abstract: A program causes a computer to execute a process including: receiving a command to connect first and second VMs through an L2 tunnel corresponding to particular QoS; instructing a first physical machine on which the first VM is running and which is connected to a plurality of physical networks through a first physical network interface device to use a first and second addresses in encapsulating in a first L3 packet a first L2 frame that the first VM decides to send to the second VM; and instructing the second physical machine, mutatis mutandis. Each physical network supports one or more levels in QoS. The first and second addresses correspond to a particular physical network that supports the particular QoS. The first address is one of addresses assigned to the first physical network interface device. The second address is one of addresses assigned to the second physical network interface device.

Abstract: A computer detects, by a physical machine serving as a migration destination of a virtual machine of a migration target, a signal transmitted from the virtual machine of the migration target in response to a migration completion of the virtual machine of the migration target to the physical machine according to a setting by a management machine; and notifies the management machine of the migration completion of the virtual machine of the migration target in response to the detection.

Abstract: A transmitter and a receiver each have an apparatus for carrying out retransmission processing at a TCP layer and an apparatus for carrying out encrypted-data communication at an IPSec layer. The apparatus operating at the IPSec layer has a buffer for storing encrypted data transmitted by the transmitter. When a request for retransmission of data is received from the receiver, in spite of an operation carried out at an IP layer, information available at the TCP layer is obtained and data corresponding to the encrypted data stored in the buffer is returned to the receiver in response to the request.

Abstract: A communication control apparatus for enabling a quality of service (QoS) to be maintained, the security against interception to be ensured, and a communication route to be switched over without any interruption of communications, and capable of restraining the processing time and the number of adjusting parameters. The communication control apparatus including a coding unit, an allocation unit, and a sending unit.

Abstract: To provide a technology capable of ensuring a communication traffic on a communication route simply by providing a communication node with this technology in a network such as the Internet where communication control devices on communication routes employed for forwarding data are not all uniformly managed. A communication traffic of a first flow that contributes to a band of communication with a partner communication device is measured, a communication traffic of a second flow is calculated so that a total communication traffic of the first flow communication traffic measured and the communication traffic of the second flow that can be generated based on a result of the measurement, converges at within a predetermined range, and the communication traffic of the second flow is generated with respect to the partner communication device on the basis of a result of the calculation.

Abstract: To provide a technology enabling a quality of service (QoS) to be kept, the security against interception to be ensured and a communication route to be switched over without interruption of communications, and capable of restraining processing time and the number of adjusting parameters.

Abstract: A transmitter redundantly transmits data in an available band range when transmitting data. A receiver discards redundancy and receives the data. The receiver also redundantly transmits ack in an available band range. Since data is redundantly transmitted/received, there is a high possibility that data may reach the opposite party normally even if one of the duplicate data is lost. Accordingly, high-speed communication can be realized. Since time no data flows through a communication route is reduced, network resources can be effectively utilized.

Abstract: A transmitter redundantly transmits data in an available band range when transmitting data. A receiver discards redundancy and receives the data. The receiver also redundantly transmits ack in an available band range. Since data is redundantly transmitted/received, there is a high possibility that data may reach the opposite party normally even if one of the duplicate data is lost. Accordingly, high-speed communication can be realized. Since time no data flows through a communication route is reduced, network resources can be effectively utilized.

Abstract: A transmitter and a receiver each have an apparatus for carrying out retransmission processing at a TCP layer and an apparatus for carrying out encrypted-data communication at an IPSec layer. The apparatus operating at the IPSec layer has a buffer for storing encrypted data transmitted by the transmitter. When a request for retransmission of data is received from the receiver, in spite of an operation carried out at an IP layer, information available at the TCP layer is obtained and data corresponding to the encrypted data stored in the buffer is returned to the receiver in response to the request.