An image processing apparatus includes a reception unit configured to receive a session start message, a determination unit configured to determine whether the session start message received by the reception unit is a session start message from a public Internet Protocol network or a session start message from a local Internet Protocol network, an acquisition unit configured to acquire a media type included in the session start message received by the reception unit, and a control unit configured to determine whether a start of a session is allowed, based on a result determined by the determination unit and the media type acquired by the acquisition unit.