Abstract: A communications apparatus for converting an IPv4 multicast packet transmit from an IPv4 terminal into an IPv6 multicast packet and transmitting the converted IPv6 multicast packet to one of a plurality of IPv6 networks. The communications apparatus has information indicating to which IPv6 network the IPv4 multicast packet to undergo conversion processing is to be transmitted. The communications apparatus then converts the received IPv4 multicast packet into an IPv6 multicast packet and transmits the converted IPv6 multicast packet to an IPv6 network where it is required to be sent.

Abstract: A communications apparatus for converting an IPv4 multicast packet transmit from an IPv4 terminal into an IPv6 multicast packet and transmitting the converted IPv6 multicast packet to one of a plurality of IPv6 networks. The communications apparatus has information indicating to which IPv6 network the IPv4 multicast packet to undergo conversion processing is to be transmitted. The communications apparatus then converts the received IPv4 multicast packet into an IPv6 multicast packet and transmits the converted IPv6 multicast packet to an IPv6 network where it is required to be sent.

Abstract: A communication unit is connected to both an IPv4 network and an IPv6 network for converting an IPv4 multicast packet into an IPv6 multicast packet. The communication unit, which has held the IPv6 multicast addresses, holds the IPv4 multicast addresses of a multicast group on the IPv4 network and the held IPv6 multicast addresses in correspondence with each other. Moreover, the communication unit converts the IPv4 multicast address of the received IPv4 multicast packet into the IPv6 multicast address held in correspondence with the IPv4 multicast address, then transmits the multicast packet to the IPv6 network.

Abstract: A communication unit is connected to both an IPv4 network and an IPv6 network for converting an IPv4 multicast packet into an IPv6 multicast packet. The communication unit, which has held the IPv6 multicast addresses, holds the IPv4 multicast addresses of a multicast group on the IPv4 network and the held IPv6 multicast addresses in correspondence with each other. Moreover, the communication unit converts the IPv4 multicast address of the received IPv4 multicast packet into the IPv6 multicast address held in correspondence with the IPv4 multicast address, then transmits the multicast packet to the IPv6 network.

Abstract: A packet communication method and a packet communication system capable of making an IPv4-compatible application operating on an information processing apparatus communicate with another information processing apparatus connected to an IPv6 network without using an address translation router. In the information processing apparatus connected to the IPv6 network incorporates, an IPv4-to-IPv6 protocol conversion control function is incorporated in a LAN driver. A protocol conversion control module receives an IPv4 packet from a protocol control module. When a send destination IPv4 address contained in a header of the packet is registered in an address translation table incorporated in the protocol conversion control module, an IPv6 address is generated to be sent onto a LAN. Unless the send destination IPv4 address contained in the packet header is registered in the address translation table incorporated in the protocol conversion control module, the IPv4 packet as received is intactly sent onto the LAN.

Abstract: A LAN switch is one component of a communications network system composed of a virtual LAN having network terminals such as personal computers connected with ports respectively. The LAN switch provides a host table for holding correspondence between each port and address information of the network terminal connected to each port and an authentication table for holding information for authenticating a user of each network terminal. If a request takes place of changing the correspondence about the source network terminal held in the host table when relaying the packets, the LAN switch prompts a user name and a password for the source network terminal, does user authentication on the basis of the information held in an authentication table, and enables rewrite of the host table and relay of the packets if the user is correct. These processes are executed for easily preventing false use of an address or tapping or false access by a malignant user as well as analyzing or recovering the erroneously set address.

Abstract: A packet communication method and a packet communication system capable of making an IPv4-compatible application operating on an information processing apparatus communicate with another information processing apparatus connected to an IPv6 network without using an address translation router. In the information processing apparatus connected to the IPv6 network, an IPv4-to-IPv6 protocol conversion control function is incorporated in a LAN driver. A protocol conversion control module receives an IPv4 packet from a protocol control module. When a send destination IPv4 address contained in a header of the packet is registered in an address translation table incorporated in the protocol conversion control module, an IPv6 address is generated to be sent onto a LAN. Unless the send destination IPv4 address contained in the packet header is registered in the address translation table incorporated in the protocol conversion control module, the IPv4 packet as received is intactly sent onto the LAN.

Abstract: A translator for coupling a first IPv4 network and a second IPv6 network having different addressing architectures for IP addresses so as not to exhaust the IP addresses of one of the two networks, a network system using the translator, and a network coupling method. When a packet is transferred from the IPv6 network to the IPv4 network, the translator assigns any of previously prepared IPv4 addresses to an IPv6 address stored in a source storing field of the IPv6 packet. The assigned address is stored in a source storing field of an IPv4 packet. A packet translation unit assigns the foregoing IPv6 address to an IPv4 address stored in a destination storing field of the IPv4 packet, when a packet is transferred from the IPv4 network to the IPv6 network, and stores this address in a destination storing field of the IPv6 packet.

Abstract: A translator for coupling a first network such as an internet protocol version 4 (IPv4) and a second network such as an internet protocol version 6 (IPv6) having different addressing architectures for IP addresses due to a difference in version or the like so as not to exhaust the IP addresses of one of the two networks, a network system using the translator, and a network coupling method therefor are provided. When a packet is transferred from the IPv6 network to the IPv4 network, the translator assigns any of a plurality of previously prepared IPv4 addresses to an IPv6 address stored in a source storing field of the IPv6 packet. The assigned address is stored in a source storing field of an IPv4 packet. A packet translation unit is provided for assigning the foregoing IPv6 address to an IPv4 address stored in a destination storing field of the IPv4 packet, when a packet is transferred from the IPv4 network to the IPv6 network, and for storing this address in a destination storing field of the IPv6 packet.

Abstract: A translator for coupling a first network such as an internet protocol version 4 (IPv4) and a second network such as an internet protocol version 6 (IPv6) having different addressing architectures for IP addresses due to a difference in version or the like so as not to exhaust the IP addresses of one of the two networks, a network system using the translator, and a network coupling method therefor are provided. When a packet is transferred from the IPv6 network to the IPv4 network, the translator assigns any of a plurality of previously prepared IPv4 addresses to an IPv6 address stored in a source storing field of the IPv6 packet. The assigned address is stored in a source storing field of an IPv4 packet. A packet translation unit is provided for assigning the foregoing IPv6 address to an IPv4 address stored in a destination storing field of the IPv4 packet, when a packet is transferred from the IPv4 network to the IPv6 network, and for storing this address in a destination storing field of the IPv6 packet.

Abstract: A translator for coupling a first network such as an internet protocol version 4 (IPv4) and a second network such as an internet protocol version 6 (IPv6) having different addressing architectures for IP addresses due to a difference in version or the like so as not to exhaust the IP addresses of one of the two networks, a network system using the translator, and a network coupling method therefor are provided. When a packet is transferred from the IPv6 network to the IPv4 network, the translator assigns any of a plurality of previously prepared IPv4 addresses to an IPv6 address stored in a source storing field of the IPv6 packet. The assigned address is stored in a source storing field of an IPv4 packet. A packet translation unit is provided for assigning the foregoing IPv6 address to an IPv4 address stored in a destination storing field of the IPv4 packet, when a packet is transferred from the IPv4 network to the IPv6 network, and for storing this address in a destination storing field of the IPv6 packet.

Abstract: In an apparatus, there are provided an IP transmitting and receiving unit for transmitting and receiving an IPv4 packet and an IPv6 packet; an IP header converting unit for performing a mutual conversion of the IPv4 packet and the IPv6 packet by an IP header conversion; a DNS substituting unit for receiving a domain information capturing request sent from an IPv4 terminal or an IPv6 terminal and substituting its process; an IPv4 address capturing unit for capturing an IPv4 address from a DHCP server; and an IP address conversion information holding unit for holding an IPv6 address of the IPv6 terminal and the IPv4 address captured by the IPv4 address capturing unit in correspondence to each other. Thus, a communication with the IPv4 terminal can be executed without preliminarily fixedly allocating the IPv4 address to the IPv6 terminal.

Abstract: The present invention provides a technology including, for example, a packet relay processing section to carry out packet relay, a packet sampling section to carry out packet sampling, a flow statistics counting section to take statistics of each flow, and a flow statistics generating section to generate a NetFlow export datagram, wherein the flow statistics counting section collectively counts the number of the packets or bytes received per unit time when the number does not exceed a threshold value and individually counts the number for each flow when the number exceeds the threshold value, and thereby a flow of abnormal traffic which is suspected to be DoS attack is efficiently detected with small amounts of resources (mainly memories).

Abstract: In an apparatus, there are provided an IP transmitting and receiving unit for transmitting and receiving an IPv4 packet and an IPv6 packet; an IP header converting unit for performing a mutual conversion of the IPv4 packet and the IPv6 packet by an IP header conversion; a DNS substituting unit for receiving a domain information capturing request sent from an IPv4 terminal or an IPv6 terminal and substituting its process; an IPv4 address capturing unit for capturing an IPv4 address from a DHCP server; and an IP address conversion information holding unit for holding an IPv6 address of the IPv6 terminal and the IPv4 address captured by the IPv4 address capturing unit in correspondence to each other. Thus, a communication with the IPv4 terminal can be executed without preliminarily fixedly allocating the IPv4 address to the IPv6 terminal.

Abstract: A packet communication method and a packet communication system capable of making an IPv4-compatible application operating on an information processing apparatus communicate with another information processing apparatus connected to an IPv6 network without using an address translation router. In the information processing apparatus connected to the IPv6 network incorporates, an IPv4-to-IPv6 protocol conversion control function is incorporated in a LAN driver. A protocol conversion control module receives an IPv4 packet from a protocol control module. When a send destination IPv4 address contained in a header of the packet is registered in an address translation table incorporated in the protocol conversion control module, an IPv6 address is generated to be sent onto a LAN. Unless the send destination IPv4 address contained in the packet header is registered in the address translation table incorporated in the protocol conversion control module, the IPv4 packet as received is intactly sent onto the LAN.

Abstract: A communications apparatus for converting an IPv4 multicast packet transmit from an IPv4 terminal into an IPv6 multicast packet and transmitting the converted IPv6 multicast packet to one of a plurality of IPv6 networks. The communications apparatus has information indicating to which IPv6 network the IPv4 multicast packet to undergo conversion processing is to be transmitted. The communications apparatus then converts the received IPv4 multicast packet into an IPv6 multicast packet and transmits the converted IPv6 multicast packet to an IPv6 network where it is required to be sent.

Abstract: A communications apparatus for converting an IPv4 multicast packet transmit from an IPv4 terminal into an IPv6 multicast packet and transmitting the converted IPv6 multicast packet to one of a plurality of IPv6 networks. The communications apparatus has information indicating to which IPv6 network the IPv4 multicast packet to undergo conversion processing is to be transmitted. The communications apparatus then converts the received IPv4 multicast packet into an IPv6 multicast packet and transmits the converted IPv6 multicast packet to an IPv6 network where it is required to be sent.

Abstract: A translator for coupling a first network such as an internet protocol version 4 (IPv4) and a second network such as an internet protocol version 6 (IPv6) having different addressing architectures for IP addresses due to a difference in version or the like so as not to exhaust the IP addresses of one of the two networks, a network system using the translator, and a network coupling method therefor are provided. When a packet is transferred from the IPv6 network to the IPv4 network, the translator assigns any of a plurality of previously prepared IPv4 addresses to an IPv6 address stored in a source storing field of the IPv6 packet. The assigned address is stored in a source storing field of an IPv4 packet. A packet translation unit is provided for assigning the foregoing IPv6 address to an IPv4 address stored in a destination storing field of the IPv4 packet, when a packet is transferred from the IPv4 network to the IPv6 network, and for storing this address in a destination storing field of the IPv6 packet.

Abstract: In an apparatus, there are provided an IP transmitting and receiving unit for transmitting and receiving an IPv4 packet and an IPv6 packet; an IP header converting unit for performing a mutual conversion of the IPv4 packet and the IPv6 packet by an IP header conversion; a DNS substituting unit for receiving a domain information capturing request sent from an IPv4 terminal or an IPv6 terminal and substituting its process; an IPv4 address capturing unit for capturing an IPv4 address from a DHCP server; and an IP address conversion information holding unit for holding an IPv6 address of the IPv6 terminal and the IPv4 address captured by the IPv4 address capturing unit in correspondence to each other. Thus, a communication with the IPv4 terminal can be executed without preliminarily fixedly allocating the IPv4 address to the IPv6 terminal.

Abstract: In an apparatus, there are provided an IP transmitting and receiving unit for transmitting and receiving an IPv4 packet and an IPv6 packet; an IP header converting unit for performing a mutual conversion of the IPv4 packet and the IPv6 packet by an IP header conversion; a DNS substituting unit for receiving a domain information capturing request sent from an IPv4 terminal or an IPv6 terminal and substituting its process; an IPv4 address capturing unit for capturing an IPv4 address from a DHCP server; and an IP address conversion information holding unit for holding an IPv6 address of the IPv6 terminal and the IPv4 address captured by the IPv4 address capturing unit in correspondence to each other. Thus, a communication with the IPv4 terminal can be executed without preliminarily fixedly allocating the IPv4 address to the IPv6 terminal.