Apparatus and method for flow control

An apparatus for performing flow control in a software defined network (SDN) environment, the apparatus comprising:

• a receiver configured to receive a first packet processing inquiry message comprising a first packet from a first switch;
• and
• a controller configured to determine whether there is a second proxy connected with a second switch and matching a first proxy connected with the first switch in response to the first packet processing inquiry message,
• wherein the controller is further configured to, in response to determining that there is a second proxy, instruct the first switch to transmit the first packet such that the first packet passes through the first proxy, and configured to, in response to determining that there is no second proxy, instruct the first switch to transmit the first packet such that the first packet bypasses the first proxy,
• wherein,
• the receiver is further configured to receive, from the second switch, a second packet processing inquiry message following the first packet processing inquiry message, and
• in response to the second packet processing inquiry message comprising a hash value or a second packet having a same source and a same destination as the first packet, the controller is further configured to make a subsequent determination on whether the second proxy is present.