Abstract: A server load sharing system having a plurality of server load balancers and a relay device. Each balancer includes a module selecting, any one of a plurality of load sharing target servers specified in their group on the basis of the virtual IP address and each allocated a unique IP address, and a module rewriting a virtual IP address of the received forwarding target packet addressed to the virtual IP address into the unique IP address of the selected server, and rewriting a source IP address of the received packet addressed to the virtual IP address into an IP address capable of specifying the other of the first and second links.

Abstract: In a communication system, a first communication apparatus includes: an application data generating unit for generating application data including data at an application level and a priority at the application level; and a lower-level packet generating unit disposed therein for generating a packet by adding to the application data a header including a destination address and a source address at a level lower than the application level. A first relay apparatus includes: a priority identifying unit disposed therein for determining whether or not a priority is set in the application data of the packet received by the first relay apparatus, and thereby identifying a first priority at the application level; and a priority control unit disposed therein for renewing a TOS field value in the header of the packet, the header being at the level lower than the application level, on the basis of the first priority.

Abstract: In a network device and a network management device managing the network device, network management processors of the network devices transmit management information of their own devices in a format displayable on the browser, e.g. XML or HTML upon occurrence of a predetermined event, and a network management processor of the network management device displays the management information.

Abstract: A relay method is provided. In the relay method, a relay apparatus receives a communication packet including a metric from a client, selects an optimal server on the basis of the metric by referring to a server table including server information including metrics of servers. Then, the relay apparatus sends the communication packet to the destination server indicated by the communication packet when the destination server is the optimal server, or, the relay apparatus sends, to the client, a destination changing packet for changing the destination server to the optimal server when the destination server is different from the optimal server.

Abstract: In a communication system, a first communication apparatus includes: an application data generating unit for generating application data including data at an application level and a priority at the application level; and a lower-level packet generating unit disposed therein for generating a packet by adding to the application data a header including a destination address and a source address at a level lower than the application level. A first relay apparatus includes: a priority identifying unit disposed therein for determining whether or not a priority is set in the application data of the packet received by the first relay apparatus, and thereby identifying a first priority at the application level; and a priority control unit disposed therein for renewing a TOS field value in the header of the packet, the header being at the level lower than the application level, on the basis of the first priority.

Abstract: A server load sharing system has a plurality of server load balancers and a relay device. Each balancer includes a module selecting, when receiving a forwarding target packet addressed to a predetermined virtual IP address via one of first and second links, any one of a plurality of load sharing target servers specified in their group on the basis of the virtual IP address and each allocated a unique IP address, and a module rewriting the virtual IP address of the received forwarding target packet addressed to the virtual IP address into the unique IP address of the selected server, and rewriting a source IP address of the received packet addressed to the virtual IP address into an IP address capable of specifying the other of the first and second links.

Abstract: In a communication control apparatus and method of the present invention, a current state of communications in a predetermined route on an IP network is detected. In response to a request for connecting a new call to the predetermined route, it is determined whether the request is accepted or rejected, based on a result of comparison of the detected state of communications in the predetermined route and a maximum amount of traffic of packets permitted for the predetermined route.