Kokusai Denshin Denwa Co., Ltd.

Fuji Electric Co., Ltd.

The University of Tokyo

Ddi Corp.

Tohru Asami

Toshikane Oda

Takahiro Kudo

Masami Kishiro

Hideaki Yamada

Yoshihiro Kawahara

Yoshihiro Ito

Osamu Maeshima

Haruki Kawakami

Masami Ishikura

A transmitting device includes: a compressing unit configured to generate and output a compressed digital signal that has been compressed, by converting an input digital signal by use of a Walsh function and extracting a specific frequency component.

Transmitting device, receiving device, and transmitting and receiving system

The object of the present invention is to provide a DNS server and terminals both of which are capable of sending and receiving communication by means of a small number of IP addresses. In the case where a firewall is not provided, when the DNS server receives an inquiry of a FQDN, it sends a broad cast frame for searching a terminal to which an IP address is assigned via all the network devices. When a terminal monitors the broad cast frame and finds the FQDN to be its own FQDN, it returns the uni-cast frame to the DNS server. When the DNS server receives the uni-cast frame, it makes a look-up table and a reverse look-up table. As a result, the terminal can receive the communication by an ordinary method. In the case where the firewall is provided, by processing an IP address conversion between the external IP address and the internal address by the use of an IP address conversion means NAT in addition to making the look-up table and the reverse look-up table, the terminal can receive communication.

DNS server, DHCP server, terminal and communication system

A network interworking device used in a communication system which has a first communication network with an IP, a second communication network and a plurality of other network interworking devices connected to the first communication network, the network interworking device being connected between the first communication network and the second communication network for converting IP packets communicated in the first communication network and information signals communicated in the second communication network with each other. The network interworking device includes a packet assembler unit for assembling information signals of a plurality of calls received from the second communication network into a single IP packet when the plurality of calls are to be transmitted to the same network interworking device.

Network interworking device for LAN/internet

An IP tunnel is constructed between routers connected with the INTERNET. A bandwidth of the IP tunnel is assured by setting up a reservation resource protocol (RSVP) on the IP tunnel. Further as a traffic control of the routers and on the IP tunnel, a frequency for sending packets, which are processed by an input processor and an output processor inside of the router, is allotted based on a ratio of the reserved bandwidth in each IP tunnel, then an algorithm for controlling the traffic is simplified. Furthermore each of the routers on the IP tunnel has a function for scheduling a reservation and manages a time period at which the virtual private network (VPN) of a type of the reservation resource protocol (RSVP) will be used, then it is possible to reserve the assurance of the bandwidth on the designated date and time in the future.

Method for constructing a VPN having an assured bandwidth

Growing community of inventors

Saitama, Japan

Tohru Asami