A communication apparatus comprising a table configured to include a correspondence between at least one of a first identifier that identifies a port from which frames are received, a second identifier that identifies a port from which frames are transmitted, a third identifier that identifies a flow related to a frame received, and a fourth identifier that identifies a flow related to a frame to be transmitted, and a fifth identifier that is different from the first to fourth identifiers, a counter equipped for each fifth identifier, and a controller configured to search the table, each time a frame is received or transmitted, for a fifth identifier by using any one of the first to fourth identifiers related to the frame as a key, and increment a counter corresponding to the fifth identifier by an amount.