Nippon Telegraph and Telephone Corporation

Yuichi Murata

Shingo Orihara

Yo Kanemoto

Yuta Iwaki

Kunio Miyamoto

Takahiro Hamada

Bo Hu

Hideo Kitazume

Yuminobu Igarashi

Masami Ueno

Yuichi Sudo

A learning device generates a character class series abstracting a structure of a predetermined character string included in each of requests to the server which have been generated in a predetermined period. Also, for each of the combinations of the predetermined identification information and the character class series included in the requests, the learning device calculates a score for update which becomes higher as the number of times of appearance of the combination is increased and becomes higher as the appearance of the combination is continued. Based on the score for update, the learning device updates the profile of each combination for determining whether the request is an attack or not.

Learning method, learning device, and learning program

A generation method includes identifying, as paths that are abstraction candidates, dynamically generated paths among paths in a profile that is used to determine whether each request to a server is an attack, and counting numbers of path variations corresponding to the respective paths that are abstraction candidates, and abstracting paths contained in the profile when a number of variations counted at the counting satisfies a certain condition, by processing circuitry.

Generation method, generation device, and recording medium

When an attack is detected, a controller samples an attack-target addressed DNS reply, received by a border router, from each of the border routers. Then, the controller adds the transmission-source IP address of the sampled DNS reply to the black list of the border router. Furthermore, upon reception of any of a target-addressed DNS reply and a target-addressed UDP subsequent fragment from the IP address that is described in the black list, the controller gives a command to the border router to discard the packet. Furthermore, the controller specifies the setting, for each of the border routers, that DNS replies to a DNS request from the target are excluded from discarding.

Control device, border router, control method, and control program

Growing community of inventors

Musashino, Japan

Yuichi Murata