Patent ID: 7797741

Claim:
A system for coping with encrypted harmful traffic in hybrid IPv4/IPv6 networks, the system comprising: an encryption key manager collecting encryption key information by a microprocessor from at least one to a plurality computer user terminals connected to the hybrid IPv4/IPv6 networks, and storing and managing the encryption key information in an encryption key database; an encryption traffic collector collecting encrypted traffic from traffic in the hybrid IPv4/IPv6 networks, wherein the encryption traffic collector collects the encrypted traffic that flows from at least a first network lead-in point to a second lead-in point, wherein each of the first and second network lead-in points is located between a IPv4 network and a IPv6 network, and the first and second network lead-in points communicate through one of the IPv4 network and the IPv6 network, wherein the encrypted traffic has an IPsec header of an end-to-end tunnel mode traffic that flows into the hybrid IPv4/IPv6 networks, and wherein traffic flows from a first computer user terminal through the first lead-in point to the second lead-in point that a second computer user terminal is connected to for receiving traffic sent from the first computer user terminal, and wherein harmful traffic is sent from a third computer user terminal, which is directly connected to the IPv4 network; an encryption key searcher searching for an encryption key used to decrypt the encrypted traffic from the encryption key database using a source IP address and a destination IP address of the encrypted traffic; a harmful traffic determiner decrypting the encrypted traffic using the encryption key and determining whether the decrypted traffic is the harmful traffic; and an encryption traffic processor, if the decrypted traffic is determined to be the harmful traffic, blocking the harmful traffic and, if the decrypted traffic is determined to be normal traffic, encrypting the normal traffic, and transferring the encrypted traffic to the second computer user terminal corresponding to the destination IP address of the traffic being sent from the first computer user terminal, wherein the blocked harmful traffic is revoked at the second lead-in point or the first lead-in point from being encrypted to the normal traffic after the traffic from the first computer user terminal has passed through either the first lead-in point or the second lead-in point, and wherein the revoked harmful traffic is not transferred as encrypted traffic to the second computer user terminal corresponding to the destination IP address of the traffic being sent from the first computer user terminal.