Transmitter, receiver, and transmitting method

摘要

According to one embodiment, a transmitting method transmits a start request for an authentication and key exchange from at least one of receivers to the transmitter, performs an authentication and key exchange for at least one of a first key common to the receivers and a second key peculiar to the at least one of the receivers, and encrypts the content by using a key shared by the transmitter and the at least one of the receivers to transmit the encrypted content to the at least one of the receivers.

主权项

1. A transmitting method for transmitting a content from a transmitter to a first receiver, the method comprising:
transmitting a content receiving request from the transmitter to the first receiver; transmitting, from the first receiver, a start request for an authentication and key exchange, the start request comprising one of a first request for generating a first key for rendering or copying a content and a second request for generating a second key for moving a content, the first key being common to the first receiver and a second receiver, and the second key being unique to the first receiver; performing one of a first authentication and key exchange and a second authentication and key exchange, the first authentication and key exchange being triggered by the first request and performed between the transmitter and the first receiver in order to generate the first key, the second authentication and key exchange being triggered by the second request and performed between the transmitter and the first receiver in order to generate the second key, the generated first key and second key being shared by the first receiver and the transmitter; transmitting, from the first receiver to the transmitter, an acknowledgement including a label of one of the first key and the second key; encrypting the content by using the one of the first key and the second key based on the label included in the acknowledgement; and transmitting the encrypted content to the first receiver, wherein the moving makes the content void at the transmitter after transmitting, and the rendering or copying does not make the content void at the transmitter after the transmitting.