Reducing data stream interruption during failure of a firewall device

A computer program product, comprising a non-transitory computer usable medium having a computer readable program code embodied therein, the computer readable program code adapted to be executed to implement a method, the method comprising:

• performing by a first firewall device a firewall function of a plurality of different firewall functions on a first redundant input data packet and outputting from the first firewall device the first redundant input data packet as a first redundant output data packet according to the firewall function;
• performing by a second firewall device only the same firewall function on a second redundant input data packet and outputting from the second firewall device the second redundant input data packet as a second redundant output data packet according to the firewall function, wherein the first and second redundant output data packets are at least substantially similar when the firewall devices are functioning properly;
• receiving by a controller the first and second redundant output data packets;
• and
• transmitting from the controller at a given time one of the first and second redundant output data packets to a target, wherein transmitting comprises transmitting from the controller the first redundant output data packet to the target while the second firewall device is failed.