Patent ID: 8582574
Filing Date: 2013-11-12
Classification: H04L

Abstract:
1. An access device for preventing transmission of copyrighted content to an external network, comprising: a packet-header analyzer which analyzes a header of a packet received from a device of a home network; a copyrighted-content sensor which detects whether the packet includes the copyrighted content, based on analysis by the packet-header analyzer for blocking transmission of the copyrighted content to the external network; an address converter which converts a source Internet Protocol (IP) address of the packet into an IP address supported by the external network if a destination address of the packet is an address corresponding to the external network, based on the analysis by the packet-header analyzer; a mapping-table generator which generates a mapping table configured to manage a mapping relationship between the source IP address of the packet and the converted IP address supported by the external network; and a packet transmitter which transmits the packet to the IP address supported by the external network, wherein the packet-header analyzer extracts time to live (TTL) information of the packet from the header of the packet, the copyrighted-content sensor determines that the packet includes the copyrighted content if a TTL value of the packet is less than a certain value equal to or less than three, the TTL value is greater than 0, and controls for blocking transmission of the copyrighted content to the external network when it is determined that the packet includes the copyrighted content.