Patent ID: 9350699
Filing Date: 2016-05-24
CPC Classification: H04L

Claim Text:
1. A method of opening a port in a firewall, the method comprising: intercepting a firewall punching packet transmitted over a firewall port to a target address in a public network, the firewall punching packet including a public source address indicating the firewall port over which the packet was transmitted; sending, in response to the firewall punching packet, a reply message to the public source address specified in the firewall punching packet, the reply message comprising a payload that contains the public source address of the firewall punching packet; if the target address of the firewall punching packet contains a predetermined port number, creating an entry in a mapping table associating a target IP address of the firewall punching packet with the public source address of the firewall punching packet; intercepting a packet sent to the firewall; if the source IP address and destination address of the intercepted packet matches an entry in the mapping table, modifying the source address of the intercepted packet to match the target address of the firewall punching packet; and forwarding the modified packet to the firewall.