Hitachi, Ltd.

Other

Alaxala Networks Corporation

Minoru Hidaka

Toshio Hirosawa

Tsutomu Ito

Takeki Yazaki

Kazuma Yumoto

Kazuyoshi Hoshino

Tomoyuki Oku

Yoshihiro Ishii

Kenichi Sakamoto

Natsuki Yokoyama

Tsuneo Terasawa

Shinichi Akahane

Masayuki Takase

Yoshio Kawamura

Shigeo Moriyama

Yoshifumi Kawamoto

Norio Saitou

Eiji Takeda

Atsushi Ueoka

Michitaka Okuno

Mitsuru Nagasaka

Takehiro Morishige

Fumihiko Uchida

Soichi Katagiri

Tatsuhiko Miyata

Satoshi Kiyoto

Miyako Matsui

Eiichi Seya

Tatuharu Yamamoto

Satoshi Kiyotou

Yoshifumi Atarashi

Massaaki Ito

Satoru Tsukada

Yutaka Nara

A first issue is to provide a packet transfer device for identifying a connection such as a TCP connection linked to a bandwidth control means, and provide a proxy acknowledgment for each identified connection such as TCP. A second issue is to provide a packet transfer device for providing a proxy acknowledgment for a connection such as TCP, and capable of improving throughput such as for TCP just by being installed at a network edge section connected to the communication terminal. As a means to resolve the first issue, a packet transfer device is provided that contains a means for identifying flows such as TCP flows for deciding if the proxy acknowledgment means requires proxy acknowledgment or not, based on the bandwidth conformance flow reported from the bandwidth control means. As a means to resolve the second issue, a packet transfer device is provided that contains a means for converting stored packets to a protocol that does make a proxy acknowledgment, and a means for transmitting the converted packets to a packet transfer device installed on the network edge oriented towards the oncoming packets.

Packet transfer device and transfer control method thereof

To control a bandwidth without the need for a large-capacity buffer. This invention provides a packet transfer apparatus connected to first device and second device, with a network therebetween, including: an input unit that receives a packet from the first device; a packet storage unit that stores the packet; a packet processing unit that stores the packet in the packet storage unit; a packet checking unit that checks whether the packet is related to data request; a packet analyzing unit that analyzes the amount of data requested by the data request; a transfer control unit that controls transfer of the packet on the basis of the analyzed amount of data; and an output unit that sends the received packet to the second device.

Packet transfer apparatus for storage system

A high quality network is provided that eliminates the sorting time for sorting through registering look-up conditions, such as source and destination MAC addresses, in a content addressable memory, by generating a routing or flow control look-up key, and then selectively activating some of the physical banks in the content addressable memory with the look-up key during look-up for the look-up conditions. The look-up key is generated by extracting a part or all of the data contained in a packet header.

Data transfer device

Session Initiation Protocol (SIP), a protocol used in VoIP (Voice over IP) communications, enables a caller to send a SIP message to a callee with his/her UserID concealed from the callee, which in turn, prevents A SIP server from making an attempt to manage the caller. If the same IP Telephone address is used whenever the IP call is made, a third party may guess the IP address easily during conversation. The SIP message sent by the caller is converted and conversion tables are managed by the SIP server. The IP Telephone modifies its IP address for each IP call. Thus, the caller can make a call to the callee with his/her UserID concealed from the callee using the SIP server with a message conversion function and communications carriers having SIP servers installed to manage the callers using their conversion tables. It is difficult to any malicious third party to guess the IP Telephone address, because the IP Telephone address is modified for each call.

Message conversion server and IP telephone

A peer-to-peer communication apparatus connected to an IP network acquires, from a peer's communication apparatus, presence information including information for judging a communication security environment of the peer's communication apparatus and a security policy to be applied by the peer's communication apparatus to a packet, displays the presence information and security policy information such that a user can judge the prosperity of the security policy information based on the presence information, and processes a data packet to be transmitted to the peer's communication apparatus in accordance with the security policy approved by the user.

Peer-to-peer communication apparatus and communication method

A method or apparatus for transferring packets, which enables fast lines to be housed for a high load service that requires many calculations in an edge node in a communication network, in which data flows are concentrated. Information obtained from an input packet is held in a table entry in the apparatus and whether to perform such a processing as encryption, etc. is decided according to the state of the source or destination of the input packet or the internal state of the apparatus, thereby performing such a processing as encryption only for necessary packets and reducing the number of calculations.

Method for packet transferring and apparatus for packet transferring

The reserved request type of searched information distribution server having a first function unit for issuing a search request to another server connected to the Internet via the Internet so as to collect desired data from a WWW server specified by the search request according to the schedule specified by the search request when receiving request of data searching in a WWW server from a client terminal, and a second function unit for receiving searched data via a communication satellite.

Reserved request type of searched information distribution server

A reserved request type of searched information distribution server having a first function unit for issuing a search request to another server connected to the Internet via the Internet so as to collect desired data from a WWW server specified by the search request according to a schedule specified by the search request when receiving request of data searching in a WWW server from a client terminal, and a second function unit for receiving searched data via a communication satellite.

A messaging processing system which includes a process control table for storing the control information of a process corresponding to access terminals connected through a public network in a form that identifiers indicating the 'priority processing' are added to the control information, and a scheduler that executes the process having the identifier indicating the 'priority processing' in preference to the other processes during the dispatching processing of the process.

Messaging processing system and method

Method and apparatus for fabricating semiconductor devices

A technique and exposure apparatus measures, with a high degree of accuracy, figure and placement errors of individual optical elements constituting optics embedded inside of an exposure apparatus or the like, with the optics kept in an embedded state as they are. The system measures the distribution of wavefront distortions in the optics while changing the positions of a light source and an image point inside an exposure field of the optics being observed. Optimal displacements of reflective surfaces constituting the optics are then found by calculation based on the measured distribution of wave-front distortions. Finally, the positions of the reflective surfaces are corrected in accordance with the calculated optimal displacements. The positions of the reflective surfaces are corrected by individually controlling displacements output by a plurality of actuators attached to each reflective surface and by mechanically modifying appropriate portions of the reflective surfaces.

Methods for measuring optical system, and method and apparatus for

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Kunitachi, Japan

Minoru Hidaka