Abstract: A server apparatus receives a query message, calculates an identifying data based on an address and a query name containing in the query message, creates a response message containing the identifying data for requesting a redirect reply or a response message containing an answer to the query name, determines whether the query message is a redirect message and further determines whether the response message containing the answer is larger than a threshold value, and finally transmits either one of the response messages.

Abstract: A determining unit determines whether a second bit string that forms an Internet Protocol Version 4 (IPv4) address is included in a first bit string that forms an address for Internet Protocol Version 6 (IPv6) connection, and further determines whether the address for IPv6 connection is an extended address extended to an address length of an IPv6 address by adding a prior determined bit to the IPv4 address, when the second bit string is determined to be included in the first bit string. A changing unit changes a priority of the address for IPv6 connection that is determined as the extended IPv6 address. A selecting unit selects preferentially a high level address for IPv6 connection during establishing connection with an external communication apparatus.

Abstract: A communication system includes a server and a router which are both connected to a first network. The server grants to a response packet destined for an anycast address sent from a communication apparatus connected to a second network, anycast address option information indicating that an anycast address of a sender of the response packet, puts a signature field for a setting of an electronic signature in the response packet; and transmits to the communication apparatus the response packet. The router receives the response packet, validates whether the response packet is sent from a legitimate server based on the anycast address option information if the response packet includes the anycast address option information. The router also sets an electronic signature based on information related with the response packet in the signature field if the response packet is sent from the legitimate server, and transmits the response packet.

Abstract: There is provided with a client device connected to a network, including: a first message sender configured to send a first request message for requesting assignment of an address to communicate in the network to one or more servers on the network; a waiting unit configured to wait for an address candidate notification message including a candidate of the address to be assigned to arrive from each server for a certain period after the first request message is sent; a message reception unit configured to receive the address candidate notification message from each server within the period after the first request message is sent; and a duplication inspection unit configured to inspect whether or not the candidate of the address included in the address candidate notification message received from each sever is already assigned to an other client device, before the period elapses after the first request message is sent.

Abstract: A communication system includes a server and a router which are both connected to a first network. The server grants to a response packet destined for an anycast address sent from a communication apparatus connected to a second network, anycast address option information indicating that an anycast address of a sender of the response packet, puts a signature field for a setting of an electronic signature in the response packet; and transmits to the communication apparatus the response packet. The router receives the response packet, validates whether the response packet is sent from a legitimate server based on the anycast address option information if the response packet includes the anycast address option information. The router also sets an electronic signature based on information related with the response packet in the signature field if the response packet is sent from the legitimate server, and transmits the response packet.

Abstract: A communication control apparatus includes: a storage device, an input device, an output device, a communication control apparatus, a main storage device and a processor (CPU). The CPU includes an address segmentation unit, a weight detector and a connection controller. The address segmentation unit splits a received packet, the weight detector detects the weight of each segment of the packet, and the connection controller employs the weight to provide connection control for the packet.

Abstract: A communication control apparatus includes: a storage device, an input device, an output device, a communication control apparatus, a main storage device and a processor (CPU). The CPU includes an address segmentation unit, a weight detector and a connection controller. The address segmentation unit splits a received packet, the weight detector detects the weight of each segment of the packet, and the connection controller employs the weight to provide connection control for the packet.

Abstract: A set-up scheme for a cut-through connection in a network system capable of realizing a high throughput, low latency internetwork communication efficiently under an internet environment. A network node checks source/destination information of the transport layer and/or a source/destination information of the network layer of a received packet, and if the checked information satisfies a prescribed condition, determines the packet to be a trigger. Then, the network node instructs another node capable of initiating a set-up operation, which may be the network node itself, to initiate the set-up of the cut-through connection for traffic corresponding to the trigger packet.

Abstract: A server apparatus receives a query message, calculates an identifying data based on an address and a query name containing in the query message, creates a response message containing the identifying data for requesting a redirect reply or a response message containing an answer to the query name, determines whether the query message is a redirect message and further determines whether the response message containing the answer is larger than a threshold value, and finally transmits either one of the response messages.

Abstract: A communication control apparatus includes a storage device configured to store corresponding weighted values for each of a plurality of predetermined portions of a sender address, a connection request receiver configured to receive a connection request packet including a connection request, a weight detector configured to obtain a weighted value corresponding to a part of the sender address assigned to the connection request packet from among the weighted values stored in the storage device, a connection controller configured to reject the connection request, when the obtained weighted value exceeds a predetermined value, by determining that a communication apparatus consumes more than a predetermined amount of a resource and discarding the connection request packet, and allow the connection request when the obtained weighted value falls within a predetermined range that is lower than the predetermined value, a weight updater configured to update the weighted values, and a packet transmitter.

Abstract: A determining unit determines whether a second bit string that forms an Internet Protocol Version 4 (IPv4) address is included in a first bit string that forms an address for Internet Protocol Version 6 (IPv6) connection, and further determines whether the address for IPv6 connection is an extended address extended to an address length of an IPv6 address by adding a prior determined bit to the IPv4 address, when the second bit string is determined to be included in the first bit string. A changing unit changes a priority of the address for IPv6 connection that is determined as the extended IPv6 address. A selecting unit selects preferentially a high level address for IPv6 connection during establishing connection with an external communication apparatus.

Abstract: A communication system includes a server and a router which are both connected to a first network. The server grants to a response packet destined for an anycast address sent from a communication apparatus connected to a second network, anycast address option information indicating that an anycast address of a sender of the response packet, puts a signature field for a setting of an electronic signature in the response packet; and transmits to the communication apparatus the response packet. The router receives the response packet, validates whether the response packet is sent from a legitimate server based on the anycast address option information if the response packet includes the anycast address option information. The router also sets an electronic signature based on information related with the response packet in the signature field if the response packet is sent from the legitimate server, and transmits the response packet.

Abstract: A communication apparatus having first address which is link local address of IPv6 and is used for communicating with node apparatus and second address which is global address acquires an IPv6 address corresponding to node apparatus, determines whether IPv6 address acquired is link local address or global address, based on prefix included in IPv6 address acquired, generates address candidate of node apparatus by combining interface ID included in IPv6 address acquired with prefix of second address, when IPv6 address acquired is determined to be link local address, generates NI-query message of ICMPv6 including address candidate as destination address, transmits NI-query message, receives NI-reply message of ICMPv6, and determines that address candidate is global address of node apparatus when NI-reply message received includes address candidate as sender address.

Abstract: A communication control apparatus includes: a storage device, an input device, an output device, a communication control apparatus, a main storage device and a processor (CPU). The CPU includes an address segmentation unit, a weight detector and a connection controller. The address segmentation unit splits a received packet, the weight detector detects the weight of each segment of the packet, and the connection controller employs the weight to provide connection control for the packet.

Abstract: A network address management system includes a router, an address data storage device, a first communication apparatus and a second communication apparatus, and included in the router is a second connection request receiver, a second prediction unit and a determination unit. The second connection request receiver receives connection data, such as an MAC address for the second communication apparatus, and the second prediction unit employs the connection data for predicting an address while the determination unit determines whether the address is unique. When the predicted address is unique, the second communication apparatus skips duplicate address detection.

Abstract: In the communication system, the filtering is realized at times of transmission and reception, by a server which attaches an identifier indicating an anycast address to a source address of a response packet, a communication device which detects the identifier indicating an anycast address in the response packet and verifies the response packet, when the source address is different from the destination address, and a boundary router which detects the identifier in the packet and verifies that the response packet is a response transmitted from the server, according to information regarding servers that is stored in advance.

Abstract: A set-up scheme for a cut-through connection in a network system capable of realizing a high throughput, low latency internetwork communication efficiently under an internet environment. A network node checks source/destination information of the transport layer and/or a source/destination information of the network layer of a received packet, and if the checked information satisfies a prescribed condition, determines the packet to be a trigger. Then, the network node instructs another node capable of initiating a set-up operation, which may be the network node itself, to initiate the set-up of the cut-through connection for traffic corresponding to the trigger packet.

Abstract: A set-up scheme for a cut-through connection in a network system capable of realizing a high throughput, low latency internetwork communication efficiently under an internet environment. A network node checks source/destination information of the transport layer and/or a source/destination information of the network layer of a received packet, and if the checked information satisfies a prescribed condition, determines the packet to be a trigger. Then, the network node instructs another node capable of initiating a set-up operation, which may be the network node itself, to initiate the set-up of the cut-through connection for traffic corresponding to the trigger packet.