Patent ID: 7574619

Claim:
A network communication apparatus comprising: a self-apparatus setting unit that sets a communication speed to be applied to communications between the network communication apparatus itself and another apparatus that is connected to the network communication apparatus via a network; an auto-negotiation unit that transmits and receives a speed at which communications can be performed between both the network communication apparatus and said another apparatus, and that sets the communication speed set by the self-apparatus setting unit to a communication speed of said another apparatus; an update unit that updates the communication speed, and that updates a connection destination ability of network media information, after completion of transmitting and receiving by the auto-negotiation unit; an energy-saving mode unit that selects an energy-saving communication speed based on a speed that the self-apparatus can meet and on the connection destination ability of network media information; and a disconnecting unit configured to disconnect a link between the network communication apparatus and said another apparatus, wherein the disconnecting unit shifts a physical layer to a loop back mode that is a state where data is transmitted to the network communication apparatus itself, thereby disconnecting the link.