Ethernet switch, and apparatus and method for expanding port

An apparatus for expanding a port, comprising:

• a receiver which receives a first incoming frame from a port connected to terminals or receives a second outgoing frame including port identification information from the port connected to high-speed switch;
• a frame transformer which adds to the first frame the port identification information of the port from which the first frame has been received;
• and an output unit which outputs the first incoming frame transformed by the frame transformer to the high-speed switch or outputs the second outgoing frame to the port corresponding to the port identification information included in the second frame.

A method of expanding a port, comprising:

• receiving a first incoming frame from a port connected to a terminal or receives a second outgoing frame including port identification information from a port connected to high-speed switch;
• adding to the first frame the port identification information of the port from which the first frame has been received;
• and outputting the first incoming frame transformed by the frame transformer to the high-speed switch or outputs the second outgoing frame to the port corresponding to the port identification information included in the second frame.