The scheme proposed baa the property that only the receiver who has the required attribute credentials can open the message corresponding to its attribute value and that the receiver need not provide to the sender any credentials.

• 该方案有如下特点：只有持有特定属性证书的接收者才能打开与其属性值相对应的消息，而接收者不需要向发送者提供任何证书。