COMMUNICATION SYSTEM, COMMUNICATION DEVICE, COMMUNICATION METHOD, AND COMPUTER PROGRAM

摘要

To securely transmit content through remote access via an external network, such as a WAN, while exceeding restrictions of an RTT and a TTL. A way of handling a flag for controlling remote access of content is explicitly defined, and an authentication method is explicitly defined when a content using device performs remote access. Thus, also in remote access, similarly to access of the related art in a household, a copyright protection environment of content based on the DTCP-IP is constructed.