The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 03, 2020
Filed:
Aug. 29, 2017
Kabushiki Kaisha Toshiba, Minato-ku, JP;
Yoshikazu Hanatani, Komae, JP;
Naoki Ogura, Yokohama, JP;
Masanobu Koike, Tama, JP;
Hiroyoshi Haruki, Kawasaki, JP;
Kabushiki Kaisha Toshiba, Minato-ku, JP;
Abstract
According to one embodiment, a management device includes a management tree storage and one or more processors. The management tree storage stores therein a binary tree including a plurality of nodes that are assigned with respective node keys. The processors update at least one of the node keys. The processors selects at least one of a first subtree and a second subtree, the first subtree and the second subtree being subtrees including leaf nodes of the binary tree, the leaf nodes corresponding to respective communication devices included in a group, the first subtree including only leaf nodes with the respective node keys assigned thereto not having been updated, the second subtree including only leaf nodes with the respective node keys assigned thereto having been updated. The processors transmit a group key encrypted using a node key assigned to a root node of the selected subtree.