Abstract:
A method of assigning user keys for broadcast encryption. According to the method, at least one unit tree in which grandparent nodes, parent nodes, and son nodes are hierarchically connected is created. User keys created to identify lower-level nodes connected to all nodes of the tree are assigned as first user keys of the nodes for all nodes of the tree, and node identification user keys of the son nodes except for the son node included in the unit tree among node identification user keys that identifies son nodes included in unit trees are assigned as second user keys of the son nodes.
Abstract:
Provided are a method of recording/reproducing data under control of a domain management system. The method includes extracting, from the write command, domain management information regarding the predetermined domain and contents, and copy control information specifying an extent of copying the contents within the predetermined domain; recording the extracted domain management information on the storage medium; generating a domain-bound flag that is used to determine whether the recording apparatus which records the contents on a storage medium is present in the predetermined domain, based on the extracted copy control information; and recording the domain-bound flag and the contents on the storage medium. Accordingly, it is possible to record contents, recording of which is limited within a predetermined domain, on a storage medium outside a slave under control of a domain management system, while preventing the contents from being reproduced within other domains.
Abstract:
An apparatus and method capable of measuring a weight load of an inflamed leg of a lab animal or a human being objectively and precisely while the lab animal or the human being is walking freely in a non-binding state. A pathway sized depending on a size and a stride of the lab animal or the human being is provided in a weight load measuring apparatus, and a weight sensor is attached to a bottom of the pathway. Thus, artificial operations to be applied to the lab animal or human being walking the pathway can be minimized such that the weight load exerted in the inflamed leg can be measured objectively and precisely with time periods.