Nippon Telegraph and Telephone Corporation

Yasutaka Okazaki

Tetsuo Takahashi

Eiji Oki

Wataru Imajuku

Atsushi Watanabe

Yukio Tsukishima

Katsuhiro Shimano

Yoshihiro Takikawa

In a disclosed backup path bandwidth keeping method for keeping bandwidth of a backup path to which an active path is switched when the active path becomes unavailable in nodes of a communication network, each node is connected to the same destination, and the method includes a backup path bandwidth keeping phase, for M (M is a natural number equal to or less than L) channels in L (L is a natural number) channels kept as backup path bandwidth, for notifying a destination-side node existing in a destination side of the backup path of identification number information of the M channels to be kept and identification information indicating that a path for which the bandwidth is to be kept is a backup path.

Device and method for correcting a path trouble in a communication network

A capacity variable link apparatus including a main signal system and a control signal system is provided. The main signal system includes: an upper layer signal accommodation part; a lower layer path termination part; and a signal switching part for dividing the upper layer signal to lower layer signals in a lower layer path group having a capacity that is determined according to an amount of traffic of the upper layer signal. The control system includes: a traffic amount measuring part for measuring the amount of traffic of the upper layer and for determining whether the capacity of the lower layer path group is to be increased or decreased according to the amount; and a signal switching management part for controlling the signal switching part according to the result of the determination.

Capacity variable link apparatus and capacity variable link setting method

Growing community of inventors

Kanagawa, Japan

Yasutaka Okazaki