A communication apparatus includes a communication unit that connects with an external device in a one-to-one relationship, the external device storing certificate information required for connection with a network; an acquisition unit that acquires the certificate information from the external device connected with the communication unit; and a connection request unit that sends a request for connection with the network to a communication management device, the request including the certificate information acquired by the acquisition unit, so that the communication management device determines whether to permit the connection with the network in response to the request received from the communication apparatus.