Relay apparatus

A relay apparatus includes multiple ports, a switch section, multiple physical layer (PHY) sections, a first control section, and a second control section. Each of the ports transmits or receives a frame. The first control section switches a subject PHY section, which is one of the multiple PHY sections and corresponds to the port receiving the frame, from an off state to an on state when the switch section is in an off state and each of the multiple PHY sections is in an off state. The second control section switches the switch section from the off state to an on state when (i) the subject PHY section is switched from the off state to the on state, (ii) the switch section is in the off state, and (iii) the multiple PHY sections except for the subject PHY section are in the off states.