Nippon Telegraph and Telephone Corporation

Osaka University

Takashi Miyamura

Nobuaki Matsuura

Shigeo Urushidani

Michihiro Aoki

Takashi Kurimoto

Keisuke Kabashima

Kohei Shiomoto

Hisashi Kojima

Ichiro Inoue

Masayuki Murata

Tomonori Takeda

Masahiro Goshima

Shinichi Arakawa

Yuki Koizumi

A virtual network control method, for adaptively controlling a topology of a virtual network formed on a physical network in response to environmental changes in the virtual network, is provided with: a step of storing the Langevin equation, as a fluctuation equation, which models the dynamics of the topology of the virtual network as a variable for controlling the number of wavelength paths on the physical network; a step of designing control parameters included in the fluctuation equation; and a step of controlling the topology of the virtual network by applying the control parameters to the fluctuation equation to change an order parameter included in the fluctuation equation when environmental changes occur in the virtual network, and by transitioning the solution of the fluctuation equation between attractors determined by the deterministic term of the fluctuation equation due to the fluctuation term of the fluctuation equation.

Virtual network control method and system based on fluctuations

An optical network has: sections for establishing optical paths; a plurality of optical edge routers for connecting external IP networks to the optical network (); and a plurality of optical cross connects, for connecting the optical edge routers by the optical paths, having switching sections with respect to an optical pulse unit. In the optical network, each of the optical edge routers has both of: (1) an optical network control instance (INSp) for maintaining topology information in the optical network and switching/signaling the optical paths; and (2) an IP network instance (INSi) for maintaining a routing table in each of the external IP networks and activating routing protocols between the external IP networks and the IP network instance. By doing this, it is possible to realize a multi-layer cooperative function and provide highly safe optical networks, etc.

Optical network, optical edge router, program thereof, cut through method, and edge router

A data transfer apparatus and a data transfer system are provided that can reduce the cost of installing communication equipment compatible with each of several dissimilar communication protocols in one exchange office and can reduce the cost of constructing the network. The data transfer apparatus includes a data reception device () that receives packets that comply with dissimilar communication protocols from upstream data transfer apparatuses (and); a content data extraction device () that extracts content data included in the packets; a line selection information storage device () that stores the line selection information for selecting communication lines that comply with dissimilar communication protocols; a line selection device () that selects the communication line compatible with content data based on the line selection information; and a data transfer device () that transfers data to downstream data transfer apparatuses (and) that are connected to the communication line that has been selected by the line selection device.

Data transfer apparatus and data transfer system

Growing community of inventors

Tokyo, Japan

Takashi Miyamura