Network system and frame communication method

A network system, comprising:

• a node configured to perform transmission and reception of a frame based on FCoE (Fibre Channel Over Ethernet);
• a network configured to transfer said frame;
• a controller configured to perform management of said node and said network;
• and
• a gateway provided with respect to said node,
• wherein said frame is classified into a control frame for communicating control information necessary for communication and a data frame for communicating data between nodes,
• wherein said gateway determines whether a frame received from said node is said control frame or said data frame, forwards said control frame to said controller, and forwards said data frame to said network,
• wherein said controller performs said management based on said control frame received from said gateway,
• wherein said network transfers said data frame received from said gateway to a destination node without through said controller,
• wherein said node comprises a transmitter and receiver configured to perform retransmission control and reordering processing with respect to said data frame,
• wherein said controller retains a node function table that indicates whether or not each node includes said transmitter and receiver,
• wherein, before said node initiates communication of said data frame with said destination node, said controller refers to said node function table to check whether or not said node and said destination node both include said transmitter and receiver,
• wherein, if said node and said destination node both include said transmitter and receiver, said controller activates said transmitter and receiver of both of said node and said destination node, and
• wherein, if said destination node does not include said transmitter and receiver, said controller deactivates said transmitter and receiver of said node.